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Über dieses Buch

This book provides insights on a broad spectrum of renewable and sustainable energy technologies from the world’s leading experts. It highlights the latest achievements in policy, research and applications, keeping readers up-to-date on progress in this rapidly advancing field. Detailed studies of technological breakthroughs and optimizations are contextualized with in-depth examinations of experimental and industrial installations, connecting lab innovations to success in the field.

The volume contains selected papers presented at technical and plenary sessions at the World Renewable Energy Congress, the world's premier conference on renewable energy and sustainable development. Held every two years, the Congress provides an international forum that attracts hundreds of delegates from more than 60 countries.

Inhaltsverzeichnis

Frontmatter

Biomass

Frontmatter

1. Development Model of Renewable Energy Policy for Sustainable Bio-Pellet Industry in Indonesia Using Interpretive Structural Method

New and renewable energy development should be encouraged because Indonesia is net importer of oil. Government subsidy for transportation and electricity is more than Rp 300 trillion per year. Presidential Decree No. 5, 2006, mandates that energy-mix target by 2025 will be 17 % for new and renewable energy. The demand growth of energy is about 7 %, compared to developing countries with only 2–3 %. This study aims to develop renewable energy policy models concerning biomass for rural electrification; to identify the factors that influence price of feed-in tariff (FIT) determination, in particular wood-based biomass; and to design the role of social forest as raw materials for bio-pellet industry in sustainable supply chain. Research method using soft systems methodology (SSM) is the application of interpretive structural modeling (ISM) and strategic assumption surfacing and testing (SAST). The results showed that the key elements of development policy model are feasible biomass energy tariff, competent human resources, coordination among related local government offices, and community participation. Other important factors are funds and investments for business, microfinance, state-owned forest lands, and smallholder plantations policy one spatial regions plan institutions. The strategic assumptions have been identified, which are sufficient supply of raw materials to industry, availability of alternative potential industrial biomass raw materials in the local areas, the obvious trade system to accelerate the model implementations that requires regulatory support from local governments, inventory land use and forest area inventory, and support of community leaders.

Erwin Susanto Sadirsan, Hermanto Siregar, Eriyatno, Evita H. Legowo

2. Features of Carbon Stock in the Biomass of Industrial Hemp and Stinging Nettle

Recently, researchers have drawn their attention to industrial hemp (

Canabis sativa

L.) and stinging nettle (

Urtica dioica

L.), as feedstocks, potentially having a wide nonfood application. The aim of the present work was to compare dry matter (DM) and carbon (C) yields as well as C concentration in the above-ground biomass, stems and shives of the mentioned crops. In this chapter, extra attention has been paid to the C accumulation in stems and shives, since stems are a more environmentally friendly resource for solid biofuel compared to the whole above-ground part of the plant, and shives are an agricultural waste.

Field experiments with industrial hemp (eight varieties) and stinging nettle (one wild nettle and two treatments of fibre nettle clone) were carried out during 2010-2012. Dew retting and water retting were used to extract the fibre. C concentration in the samples of hemp and nettle was determined by wet oxidation with dichromate.

DM yield of the above-ground biomass of hemp amounted to an average of 10607 kg ha

1

, of stems 9063 kg ha

1

with high C concentrations of 555 and 568 g kg

1

DM, respectively. DM yield of the nettle declined along with a harvest year and ranged from 11604 kg ha

1

(2010) to 5596 kg ha

1

(2012) averaging 7589 kg ha

−1

per trial. DM yield of wild nettle was more than twice as low as that of fibre nettle clone (on average 3945 kg ha

1

vs 9411 kg ha

1

).

C stock in stems of hemp and nettle amounted to an average of 5149 and 3719 kg ha

1

, respectively. DM yield was a weighted factor for C yield.

Shives, which are the woody residue left over from the processing of hemp and nettle straw appeared very rich in C the concentration of which in hemp shives varied in the range of 564-602 g kg

1

DM and in nettle shives 543-596 g kg

1

DM. The retting method (R) significantly (

P

  0.01) affected the C concentration in nettle shives.

The high heating value (HHV) of biomass, stems and shives of hemp and nettle was determined, and the theoretical accumulation of CO

2

in biomass per ha was calculated.

Results of this study showed that the hemp and fibre clones of stinging nettle could be promising candidates for bioenergy production. The CO

2

content fixed into the biomass of the studied crops might contribute towards the reduction of climate warming.

B. Butkutė, I. Liaudanskienė, Z. Jankauskienė, E. Gruzdevienė, J. Cesevičienė, K. Amalevičiūtė

3. Obtaining Long-Chain Esters with Lubricant Properties from Sesame Biomass (Sesamum indicum)

Biolubricants are defined like long-chain esters that have lubricant properties and can be obtained from animal or vegetal resources. In this work, the obtainment of the biolubricant by the transesterification of the sesame methyl and ethyl biodiesel in the presence of polyalcohol (trimethylolpropane—TMP) is reported. To conduct the experiment, a distillation-fractioned system was adapted. The reaction conditions were: 3/1 biodiesel/TMP molar ratio, 2 wt% of sodium methoxide catalyst, and reaction temperature and time 110 °C and 6 h respectively. Physicochemical properties like acid value, iodine value, kinematic viscosity at 40 °C, and density at 20 °C were determined. The products were characterized by infrared spectroscopy and

1

H and

13

C nuclear magnetic resonance (NMR). The thermogravimetric analysis (TGA) of the bioproducts was realized and the main thermal events were evaluated.

Tathilene Bezerra Mota Gomes Arruda, Francisco Eduardo Arruda Rodrigues, Manoel Barbosa Dantas, Solange Assunção Quintella, David Thomas Duarte Arruda, Célio Loureiro Cavalcante, Nágila Maria Pontes Silva Ricardo

4. Biodiesel from Jatropha Oil

In this chapter, we provide an overview of the currently available information on the different process steps of the production of biodiesel from

Jatropha curcas

L. (JCL). Based on the collection of data and information, the best available practice, the shortcomings and the potential environmental risks, and benefits are discussed for each production step. The chapter concludes with a call for general precaution and application of science.

Ebtisam K. Heikal, Salah A. Khalil, Ismaeil K. Abdou

5. Solid Acid Catalyst Derived from Coffee Residue for Biodiesel Production

Biodiesel is a free fatty acid methyl ester (FAME) produced from transesterification of oil and short-chain alcohol. Nowadays, the cost of conventional biodiesel production might not be competitive with petro-diesel due to the cost of refined oil as a main feedstock. Many challenging researches have proposed method or technology to efficiently produce biodiesel. One of the most important knowledge is the synthesis of the suitable catalyst for biodiesel production. Solid acid catalyst is a promising catalyst to produce biodiesel from low-cost feedstocks since it can catalyze simultaneously esterification of free fatty acid (FFA) and transesterification of triglyceride. To improve the biodiesel CO

2

cycle, the waste material, coffee residue, was selected as a supported catalyst. It provides the appropriate textural properties such as high surface area with mesoporous structure and hydrophobic properties. The sulfonation with concentrated H

2

SO

4

was used for additional acidic functional group which exhibits a strong protonic acid site density. Therefore, this research aims to synthesize sulfonated activated carbon derived from coffee residue (SCAC) to catalyze esterification of caprylic acid as a model of FFA. The sulfonation temperature varied from 140 to 200 °C as named SCAC-140, SCAC-160, SCAC-180, and SCAC-200 catalysts.

After sulfonation process, the X-ray diffraction (XRD) patterns of all catalysts were similar to coffee residue activated carbon (CAC) as a support. A few, broad peak at 2θ = 15–30° and 30–50°, were related to amorphous carbon and graphene sheet at the plane C (101), respectively. Fourier transform infrared spectroscopy (FT-IR) of CAC at 3400 cm

− 1

was absent which confirmed the hydrophobic property of this support. FT-IR spectra of SCAC catalysts illustrated the acid function as 3400, 1700, 1600, 1300, 1000, and 1100 cm

− 1

, which is related to O–H stretching mode of COOH and phenolic, C═O of COOH, C═C of polyaromatic, O═S═O symmetric SO

2

stretching, O═S═O asymmetric SO

2

stretching, respectively. SCAC-180 catalyst exhibited the highest initial rate due to the highest total acid site density which included sulfonated, carboxylic, and phenolic group. At 2 h, SCAC-200 showed the highest caprylic acid conversion while SCAC-140 provided the lowest caprylic acid conversion. It was probably due to the textural and structural properties of these synthesized catalysts. All of synthesized carbon catalysts demonstrated the higher catalytic activity than that of Amberlyst-15. However, the solid acid catalyst still provided a lower catalytic activity as compared to homogeneous H

2

SO

4

catalyst.

Kanokwan Ngaosuwan

6. Evaluation of Energy Demand and Air Emissions by Using the Long-range Energy Alternatives Planning (LEAP) Model in Transport Sector of Punjab, Pakistan

Air pollution is an emerging environmental issue in major cities of Pakistan. One of the major causes of air pollution is urban transportation. The purpose of this chapter is to provide a critical overview of air pollution due to transport emissions and evaluation of energy demand for this sector as well. Long-range Energy Alternatives Planning (LEAP) model was used to present existing scenario and future projections of energy capacity in transport sector of Punjab province of Pakistan. Diesel- and gasoline-based vehicular emissions and their growth rates in the next 30 years were anticipated according to current situation. Solar energy and biodiesel along with other alternative scenarios were proposed to avoid air emissions and shortfall of diesel fuel for passenger transport in near future. The results indicated that the number of vehicles and vehicular emissions were increasing with increasing population size leading to high energy consumption. The growth rate of vehicles resulted as 15.6 % with population growth rate of 1.82 % per annum, the highest growth rate of motorcycles was 10 % followed by 8.2 % of cars. The alternative scenarios given in this research will not only reduce pollutants in the air but also provide best replaceable cost-effective fuel for demand fulfillment.

Sheikh Saeed Ahmad, Syeda Qamar Batool

7. Issues and Challenges of Implementing Waste-to-Energy Practices in India

India’s rapid development and urbanisation have led to major issues and challenges with the provision of adequate waste and energy management services. Conversion of waste-to-energy (WtE) through incineration is now an established method in developed countries for reducing waste mass and volume whilst simultaneously providing heat and power. However, the uptake of WtE technologies in developing countries has not been so successful. This study aims to identify the main issues and challenges with improving municipal solid waste (MSW) management and implementing WtE technologies in India. Specifically, we provide recommendations on actions to be taken to improve waste management and promote WtE technologies. In order to achieve this, we survey and conduct a workshop in India with over 50 participants comprising 26 government body members, 20 industry practitioners and 6 academics involved in waste management in India. Data are gathered on the social, political, technical, financial and environmental barriers to WtE and MSW management. We find that over 35 % of government body members perceive the major problem to be poor waste segregation. In comparison, industries feel that there is a lack of government support in the form of incentives and thought the ongoing challenge remains with finding a technology that can handle the characteristics of domestic waste in India. Interestingly, there seems to be minimal opposition to WtE from the public and environmentalist, which are some of the main issues in developed countries. Recommendations arising from this study are that key improvements are required in education at institutional levels, policies and regulations on the disposal and handling of MSW and financial support from central government to make plants economically viable. There is also a greater need for an increase in collaboration and communication among central and local governments, industries and communities. Further research will be conducted to gather public opinions regarding MSW management and WtE projects in India.

J. D. Nixon, D. Wright, P. K. Dey, J. A. Scott, S. Sagi, S. K. Ghosh

8. The Variation of Ash and Inorganic Elements Concentrations in the Biomass of Lithuania-Grown Switchgrass (Panicum Virgatum L.)

Switchgrass (SG) is a perennial grass of C4 type of photosynthesis and has been identified as a potential biomass crop in North America. In Europe, this species has been studied in the Atlantic maritime climate zone and in southern countries. In Lithuania, SG is a novel nonfood crop, whose investigation as a multiuse bioenergy plant, particularly as a feedstock for solid biofuel, has just been started. In this study, our attention was focused on the accumulation of biomass components that have an impact on air pollution and corrosion of combustion equipment, as well as slagging. We quantified the contents of ash and major elements of whole aboveground biomass, stems, leaves, and panicles of SG accessions, promising for growing under Lithuanian conditions. The trials were conducted during 2010–2014 at the Lithuanian Research Centre for Agriculture and Forestry on an

Endocalcari-Epihypogleyic Cambisol (CMg-p-w-can)

. Chemical composition of the biomass was assayed by reference methods.

SG biomass, cut at seed maturity had N, ash, K, Cl, Si, and S concentrations averaging 7.94, 56.5, 12.4, 2.79, 4.26, and 0.92 o kg

−1

DM respectively. Biomass of SG plants from a collection planted in 2010 had less ash, Mg, and N in both harvesting years than SG from the collection set up in 2011. Biomass of C3 energy plant reed canary grass (RCG) contained higher ash, K, N, S, and Cl concentrations (66.8, 19.1, 14.3, 1.41, and 7.02 g kg

−1

DM respectively) compared to those of SG. Genotypic variability in the inorganic composition occurred within SG genotype, but the differences among years were greater than those among accessions. With a delay in harvesting, the greatest reduction occurred in K and Cl concentrations: from September to February K concentration in the biomass of whole aboveground plant part (WP) changed from 12.3 to 3.25 g kg

−1

DM and that of Cl altered from 2.26 to 0.590 g kg

−1

DM, i.e., decreased by 74 %. Ash, N, and Mg concentration in the biomass declined by 41, 52, and 47 % compared with the biomass cut at seed maturity. Concentrations of ash, Ca, Mg, Si, N, and S in the biomass of stems of all harvesting dates were the lowest compared with the biomass of leaves and panicles. Concentration of K and Cl was practically equal in all plant parts at the respective harvesting time. For all harvesting dates, N and S concentrations in panicles were the highest.

Summarising our data presented in the current and previous papers we conclude that SG could be a useful perennial crop with a high potential of dry matter (DM) yield and adequate quality for renewable energy purposes and suitable for cultivation under conditions of nemoral environmental zone of Lithuania. By quality, overwintered biomass is the most appropriate for biofuel production compared to that of harvested in the autumn.

B. Butkutė, J. Cesevičienė, N. Lemežienė, E. Norkevičienė, G. Dabkevičienė, Ž. Liatukas

9. Microwave Pyrolysis Process Potential of Waste Jatropha Curcas Seed Cake

This chapter aims to express the potential of waste

Jatropha curcas

seed cake (JCSC) as an interesting option for energy generation. The results obtained by microwave pyrolysis (MWP) process, undoubtedly, indicate that the remaining organic liquid substances contained in JCSC, the solid residue obtained from the process, and the gaseous fraction are still a potential energy source that can be explored. The exploitation is particularly interesting in cases where an extensive production of this type of biomass waste exists and its transportation implies extensive paths and additional costs.

Jatropha Curcas

for Galapagos Islands” project is a current initiative aimed to reduce the requirements of fossil fuels for Galapagos Islands, which is framed under the “Zero fossil fuels for Galapagos Islands” national objective. The project is focused on gathering

J. curcas

fruit from living fences along the rural areas of the Province Manabí (Ecuador) to extract oil in small-scale facilities. The extracted oil is refined and transported to Galapagos Islands where it is used as biofuel for internal combustion engine generators to provide electricity to the islands. Although the by-products of extraction are currently not being exploited as an energy source, this possibility is seen as a remarkable choice for final disposition and energy generation improvement. In 2012, especially in this particular case, seed cake production was estimated to be 213 t/year as a result of its exponential growth since 2009.

Conventional pyrolysis presents some inconvenient situations, such as resistance to heat transfer, heat loss, and lack of fast heating. Taking into account that short operation/retention times are preferred in cases with growing demand, and low energy-intensive extraction technologies maximize the energy output of the primary energy source, MWP appears as a suitable option to be applied.

The available JCSC was assayed in a bench-scale MWP batch process that allows tar and chars formation and their separation for analysis. During the process, MWP operating conditions were programmed to reach 550 °C in 30 min from room temperature and maintain this condition for an additional 10 min. Also, JCSC was previously assayed to establish the content of volatile organic compounds with the purpose of estimating the organic liquid substances yield in case of a potential extraction. Liquid products (bio-oil) were analyzed through gas chromatography coupled with a mass-spectrometer detector (GC-MS) in order to determine the most representative compounds in a qualitative-basis. Their functional groups profile was obtained through a Fourier-Transform Infrared Spectroscopy (FTIR) assay. Bulk properties, such as density and calorific value, were obtained by applying existing standard methods suitable for diesel fuel. Analysis results were used to estimate its behavior as a liquid fuel by comparing the results with diesel-fuel quality standards and characteristics. In addition, calorific value, proximal and ultimate biomass analyses were developed for solid products in order to assess the suitability of a potential use as solid fuel.

The results show that the maximum content of potential liquid fuel substances is around 75 %, which leads to a conclusion that liquid fuel extraction by thermal methods is a suitable option to be evaluated regarding an augmentation of liquid fuel yield.

Ricardo A. Narváez C., Valeria Ramírez, Diego Chulde, Sebastián Espinoza, Jesús López-Villada

Fuel Cells

Frontmatter

10. Fuel Processing of Low-Sulfur Diesel for Fuel Cell Systems

Fuel processing is the umbrella term for a variety of chemical processes aiming at the provision of a hydrogen-rich gas mixture to be fed into the anode of a fuel cell. Among them, the most important ones are desulfurization, reforming, water-gas-shift reaction, preferential oxidation, and catalytic combustion. At Juelich, all these processes are under investigation. This contribution concentrates on autothermal reforming (ATR) of different synthetic and fossil fuels with Juelich’s reactor ATR 13. ATR 13 was developed within the European project Fuel Cell Based Power Generation (FCGEN). Here, special emphasis is on using diesel fuel SD10. SD10 is a conventional low-sulfur diesel, currently used for truck engine testing. ATR 13’s power class of 3–5 kWe is particularly interesting for fuel cell systems with polymer electrolyte fuel cells (PEFCs) working as auxiliary power units (APUs) for onboard power supply in trucks. During autothermal reforming, liquid fuels such as diesel are converted together with air and steam into a hydrogen-rich gas by means of catalysis. The design and construction of ATR 13 was particularly optimized with respect to its power density, since ATR 13 will be assembled in an allocated and limited space at the bottom of a conventional truck. As a result, a high value of 3.6 kW/l was reached. Intensive experimental evaluation of ATR 13’s operational behavior was done and will be reported in this chapter.

Joachim Pasel, Remzi Can Samsun, Ralf Peters, Detlef Stolten

11. Basic Study on the Application of the Fuel Cell System Operated by Kerosene to Vessel

The CO

2

emissions from ocean-going vessels in 2007 increased by 86 % to about 900 million in comparison with 1990, and it was 3 % of total CO

2

emissions. If measures are not taken in reducing CO

2

emissions from ocean-going vessels, it is assumed, by 2050, to increase six times against 1990.

Therefore, from January 1, 2013,the International Maritime Organization (IMO) started to regulate the CO

2

emissions from the ocean-going vessels. Japanese shipping and marine machinery companies had developed the system that reduced the CO

2

emissions from the ocean-going vessels. With regard to the regulation of the NO

x

emissions from the ocean-going vessels, IMO had the phased regulation of it, and IMO will do NO

x

Tier III regulations in 2021.

With regard to the application of renewable energy to vessels, some vessels with photovoltaic panels were operated by Japanese shipping companies. Therefore, the author suggested the application of the fuel cell system that did not release air pollution gases to vessels.

Kazuyoshi Sumi

12. System Modelling for Hybrid Solar Hydrogen Generation and Solar Heating Configurations for Domestic Application

Hydrogen generation has the potential to deliver an environmentally friendly, low-cost, and renewable energy source. One promising generation method is solar water splitting via a photoelectrochemical (PEC) reaction as an alternative to a combined photovoltaic-electrolyser system. Although PEC technology shows potential, the efficiency of this technology is currently limited by thermodynamics and technical issues in implementation. The development of novel materials is one route for improvements in PEC system efficiencies. In particular, with multiple band-gap electrodes, the thermodynamic efficiency, and so the overall generated hydrogen quantity, can be increased.

In the case of applications where there are heating requirements beyond the need to generate hydrogen, there are further options for extracting energy from the solar resource. Longer wavelength radiation not used by the PEC system may be available for use. Just as it is possible to have a photovoltaic–thermal (PV/T) hybrid system which generates both electricity and heat, a PEC unit may also be combined with a solar thermal unit as a hybrid PEC/T system. This combined heat and power (CHP) system will deliver heat directly and also both heat and power through the use of the hydrogen as a fuel in, for instance, a fuel cell.

Despite the promise of PEC technology, there is little research in modelling and system simulation and especially for hybrid systems. Systems’ modelling is a prerequisite for optimal design, especially for the design and exploration of novel configurations. A system model of a dwelling, with varying heat and power demands, together with a hybrid PEC/T system for meeting these demands, has been developed and implemented in Matrix Laboratory (MATLAB). The full system integrates a PEC unit for hydrogen generation, a solar thermal unit, a proton exchange membrane (PEM) fuel cell, a hydrogen storage tank, and a buffer tank for heat storage. The model has been evaluated through a case study consisting of a typical three-person household in the UK. The aim of the case study is to investigate present and near-future capabilities of renewable energy supply and CO

2

emission reduction subject to the UK building energy regulations. Results show that single band-gap photo-electrode materials are not able to meet the energy demands of the household adequately if the demand includes power and both space and hot water heating. However, with novel multiple band-gap electrodes, in a hybrid CHP system, the system efficiency can be significantly increased, and we demonstrate the potential to help meet the comprehensive demands of a typical household through the development of novel materials for PEC reactions.

Krisztian Ronaszegi, Dan J L Brett, Eric S Fraga

13. An Integrated System for Energy-efficient Exhaust Aftertreatment for Heavy-duty Vehicles

This chapter presents a unique system approach applied in a joint academic–industrial research programme, E4 Mistra, to attain the goals of high energy efficiency and low emissions in an exhaust aftertreatment system for heavy-duty vehicles. The high energy efficiency is achieved by heat recuperation, onboard hydrogen production for NO

x

reduction, and by finding new solutions for making the aftertreatment system active at low exhaust temperatures. To reach low particulate emissions, a mechanical filter using a sintered metal powder is developed and coated with catalytic material to improve the soot oxidation efficiency. Low NO

x

emissions are achieved by an efficient NO

x

reduction catalyst.

The integrated E4 Mistra system comprises four technological advances: thermoelectric (TE) materials for heat recuperation, catalytic reduction of NO

x

over innovative catalyst substrates using either the onboard diesel or biodiesel, H

2

from a high-efficiency fuel reformer, and particulate filtration over a porous metal filter. The TE materials are used in a TE generator (TEG) which converts thermal energy into electricity. The TEG is used to recuperate heat from the exhaust-gas recirculation (EGR) circuit of heavy-duty trucks and is expected to generate ~1 kW electric power from 20 kW heat in the exhaust gas. The TEG is integrated in a plate heat exchanger (HEX) designed particularly for this application. Apart from the knowledge and experiences in TEG and heat exchange technologies, a thorough fluid dynamics and TE analysis are performed in this project to understand the governing processes and optimize the system accordingly.

The components of the E4 Mistra system are explained in the chapter in addition to test results, which show the system’s capacity for H

2

production, NO

x

conversion, particulate matter filtration and soot oxidation, and finally electric power generation via heat recuperation from the exhaust gas using the developed TEG–HEX system.

Jazaer Dawody, Lennart Andersson, Lars J. Pettersson, Moa Ziethèn Granlund, Hanna Härelind, Fredrik Gunnarsson, Anders Palmqvist, Rickard Heijl, Ronnie Andersson, Olle Högblom, Lennart Holmgren, Per-Olof Larsson, Fredrik Andreasson

14. Cost-effectiveness and Potential of Greenhouse Gas Mitigation through the Support of Renewable Transport Fuels in Iceland

The system dynamics model of Iceland’s energy systems (UniSyD_IS) is used to explore the potential transition paths towards renewable transport fuels with implications for greenhouse gas (GHG) emissions and mitigation costs. The study focuses on Iceland’s potential fuel pathways including renewable electricity, hydrogen from electrolysis, biogas from municipal wastes, bioethanol from lignocellulosic biomass, and biodiesel from oil seeds and waste oils.

The vehicle fleet is divided into light- and heavy-duty vehicles, and each fleet consists of different alternative fuel vehicles. The model allocates the forecasted fleet growth among different vehicle types based on consumers’ preferences towards vehicle attributes and social network influences.

Oil price, carbon tax, renewable fuel supply–push, and government incentives are selected as the fundamental factors for scenario analysis. The results show that the transitions to renewable transport fuels seem to be feasible economically, initially, through biogas and then through uptake of hydrogen and electric vehicles. The cost-effectiveness analysis in UniSyD_IS indicates that the initial momentum of alternative fuels will not only mitigate GHG emissions but also could provide net benefits from an overall energy system and consumer perspective.

Ehsan Shafiei, Brynhildur Davidsdottir, Jonathan Leaver, Hlynur Stefansson, Eyjolfur Ingi Asgeirsson

15. Parametric Study of Polymer Electrolyte Membrane Fuel Cell Performance Using CFD Modelling

A comprehensive three-dimensional, isothermal, steady-state, straight-channel proton exchange membrane (PEM) fuel cell model was developed to investigate the transport limitations of fresh reactants at high current densities. The model is created based on the existing models in literature to predict the reactant’s transport limitations at higher current densities using three-dimensional framework. A user-defined function (UDF) code was developed considering source terms for porous zones, effective diffusivity models for species transport inside cells and electrochemistry algorithm to predict cell voltage at an average current density. Water transport through membrane was implemented considering electroosmotic drag and back diffusion inside PEM fuel cell. Simulation-predicted cell performances for different average current densities were validated with experimental results, and the effect of design parameters on cell performance is obtained using parametric studies. Parametric studies were performed to determine the best possible operating and geometrical design parameters of PEM fuel cell.

Angus Hood, Shaun Slater, Matthew Bouchet, Sheikh Zahidul Islam, Mamdud Hossain

16. Proton Modified Pt Zeolite Fuel Cell Electrocatalysts

NaY zeolite has been selected as a suitable material to host 1.5 wt.% platinum (Pt) loading on zeolite using ion-exchange methods of Pt(NH

3

)

4

(NO

3

)

2

without excess NH

4

NO

3

nitrate and Pt(NH

3

)

4

(NO

3

)

2

with excess NH

4

NO

3

nitrate. The structure/reactivity relationship of Pt nanoparticle was experimentally studied via Nafion

@

-bound electrodes to investigate the interaction nature of Pt with zeolite and electron transfer. By using extended X-ray adsorption fine-structure (EXAFS) technique, Pt particle size was predicted as 0.7–1.5 nm. It was found Pt oxides can be electrochemically reduced via a hydrogen ‘spillover’ phenomenon. A highly dispersed small Pt particle distribution could be achieved with excessive H

+

ions on zeolite acidic sites.

Jun Yao, Yufeng Yao, Hossein Mirzaii

17. Improved Dynamic Response and Range in Microbial Fuel Cell-Based Volatile Fatty Acid Sensor by Using Poised Potential

Low-cost measurement of the concentration of key volatile fatty acids (VFAs) would be very useful to improve the operation of a number of important bioprocesses, through monitoring and control. In situ microbial fuel cells (MFC)-based VFA sensors could replace the current generation of relatively complicated and expensive techniques for online VFA analysis. Cyclic voltammetry (CV) was used to determine the oxidation peak potentials for three VFA species (acetic, butyric and propionic). The dynamic behaviours and static sensitivities were recorded for 10-ml single chamber cubic MFC-based VFA sensors, separately acclimated on acetate, butyrate and propionate, while the anode was poised at a potential corresponding to the oxidation peak from CVs. The current responses at the fixed working electrode potentials were analysed for each VFA sensor in response to different concentration (0–250 mg/L) of the corresponding and other VFA species. When corresponding VFAs were supplied to the sensors, the range of the sensor was increased from 40 to 220 mg/L with no response to other VFA species in acetate- and propionate-enriched reactors.

Amandeep Kaur, Richard M. Dinsdale, Alan J. Guwy, Giuliano C. Premier

18. The Application of Solar-Powered Polymer Electrolyte Membrane (PEM) Electrolysers for the Sustainable Production of Hydrogen Gas as Fuel for Domestic Cooking

Hydrogen generation systems coupled with renewable energy systems such as photovoltaic panels can have a role as sustainable energy generation systems for independent applications that can also have a significant part in tackling energy poverty. This chapter examines a system that consists of a polymer electrolyte membrane (PEM) electrolyser powered by photovoltaic panels with the purpose to use the produced hydrogen as cooking fuel for domestic applications. It describes a small-scale experimental study of a PEM electrolyser powered by operational data from a photovoltaic panel system installed in Brunel University, UK, and the University of Technology, Kingston, Jamaica. The results show that maximum efficiency of the electrolyser was 62.8 % for a day with constantly high irradiance and 47 % for a day with volatile irradiance.

Evangelia Topriska, Maria Kolokotroni, Zahir Dehouche, Ruth Potopsingh, Earle Wilson

19. Surface Modification and Optimization of Semiconductor ns-TiO2–WO3 Admixed Photoelectrode in Regard to Solar Hydrogen Production

To minimize the harmful effects of commercial energies like fossil fuel and nuclear energy on our environment, research is going on to find clean and renewable sources of energy. The main efforts of researchers nowadays is to harness solar energy for the production of clean hydrogen fuels by a photoelectrochemical (PEC) cell which represents a very attractive but challenging alternative. Some strategies have been developed to improve PEC performances of the photoelectrode materials, including doping for enhancing visible light absorption in the wide bandgap semiconductor or promoting charge transport in the narrow bandgap semiconductor, respectively. This chapter deals with the investigation on the optimization of ns-WO

3

–TiO

2

admixed/Ti with respect to optimum photoelectrode area for semiconductor septum (SC-SEP) PEC solar cell. The motivation of the present work was to prepare an electrode having high-effective surface area and hence better quantum yield and improved PEC activity. Several attempts have been made to bring spectral response of TiO

2

into visible or near visible region. It is known that the spectral response of the TiO

2

films can be improved through admixing with appropriate oxides. The surface morphology, structural, and PEC characterization of the bare TiO

2

as well as the TiO

2

overlaid with WO

3

thin film admixtures have been investigated in relation to hydrogen production through SC-SEP PEC solar cell. The PEC response of ns-WO

3

–TiO

2

photo electrodes for four different electrode areas has been measured to explore the effect of electrode area on the output power in a chemical fuel (i.e., H

2

) produced by SC-SEP PEC cell. This was done for determining the electrode area for optimum electrical output and hydrogen production. The PEC cell having ns-WO

3

–TiO

2

admixed/Ti photoanode of several geometric areas like 0.5, 1.0, 1.5, 2.0, and 2.5 cm

2

were fabricated and characterized. It has been found that the photoanode area corresponding to optimum electrical output and hydrogen production rate corresponds to 1.0 cm

2

. The ns-WO

3

–TiO

2

exhibited a high photocurrent and photovoltage of 15.6 mA cm

–2

, 960 mV, respectively. The ns-WO

3

–TiO

2

electrode exhibited a higher hydrogen gas evolution rate of 13.8 l h

–1

m

−2

.

Mridula Tripathi, Priyanka Chawla

20. Hydrogen for Mobility: An Assessment from Economic, Energetic, and Ecological Point of View

In this chapter, the role of hydrogen as storage for surplus electricity from renewable energy sources (RES) and as a fuel for transport is discussed. The different energy supply chains based on the use of electricity from RES in passenger cars are analyzed. These analyses are conducted mainly from economic point of view but also energetic and ecological aspects are shortly addressed.

Amela Ajanovic, Reinhard Haas

Geothermal Energy

Frontmatter

21. Hydrogeothermal Potential of the Belgrade City Area, the Capital of Serbia First Assessment

The first assessment of hydrogeothermal potential of the Belgrade city area was carried out up to the depth of 300 m. The criterion for defining the in-depth cut of the research was based on financial viability of resource exploitation, and it is related to the method of drilling exploitation boreholes. The temperatures of the groundwater resources up to 300 m deep, range from 12 to 25 °C, so their use for the sake of the building air-conditioning is determined by the application of heat pumps. According to the assessed quantities of hydrogeothermal resources (kg/s), the temperature difference which can be achieved on the temperature exchanger (°C) and, finally, the specific heat capacity of the water (KJ/kg/°C), the total hydrogeothermal potential of the Belgrade city area is approximately 1200 MW. Half of the total heating requirements of the urban residential and business funds in the Belgrade city area is met with the district heating system, and the other half is met with the electric energy, up to 20 %; gas, 20 %; and hard mineral fossil fuels (coal, wood), 10 %. The total installed capacity of the heating plants is about 2500 MW, and it can be concluded that hydrogeothermal resources could meet about 50 % of the city’s heating needs. According to the above-mentioned data, hydrogeothermal resources are a strategically significant resource for the further development of the Belgrade city area.

Dejan Milenic, Ana Vranjes, Nenad Doroslovac

22. Automatic Optimization of Multiple Borehole Heat Exchanger Fields

Borehole heat exchangers (BHE) are often applied in multiple BHE fields. In current planning practice, interaction between adjacent BHEs is rarely considered, and all BHEs are operated in the same mode. This means, potential adverse effects from superimposed cold or heat plumes, which simultaneously evolve around individual neighboring BHEs, are neglected. The long-term heat extraction over decades, however, may lead to a significant local cooling, especially in the interior of the field. As a consequence, the performance of the complete ground source heat pump (GSHP) system is attenuated, and ground temperatures below regulation thresholds may develop. In our work, we employ mathematical optimization techniques to strategically operate and arrange BHEs in such fields. Linear programming and an evolutionary algorithm are applied in combination with analytical equations to solve realistic problems. The presented methodology is flexible and robust, and it can be applied to various conditions. The two scenarios studied in this chapter represent conditions with negligible and significant groundwater flow. We inspect a field with 36 BHEs, which has a seasonally variable heating energy demand. It is demonstrated, by taking the maximum temperature decline in the ground as objective, that the BHE field performance can be improved by both case-specific ideal arrangement and time-dependently regulated individual BHE operation. It is found that instead of standard lattice arrangements, optimized geometries are favorable, with BHEs concentrated along the fringe of a field. Apparently, this enhances lateral conductive heat provision into the field. Groundwater flow means additional energy provision by advection towards the field.

Peter Bayer, Markus Beck, Michael de Paly

23. Thermo-economic Study of Hybrid Thermal Solar and Geothermal Heat Pumps System in Algeria

In this chapter, the sizing and thermo-economic analysis of hybrid solar thermal and ground source heat pump (GSHP) systems for water and space heating and cooling was carried out. The houses selected for the proposed study are located in rural areas at three different climate regions in Algeria.

The software RETScreen was used to evaluate the technical and economical feasibility of the hybrid system. The software can be used worldwide to evaluate the energy production and savings, costs, emission reductions, financial viability, and risk for various types of clean energy technologies.

Different scenarios into the combined system (geothermal heat pump and thermal solar collectors) have been defined and analyzed using RETScreen software. A comparative analysis of these different scenarios was conducted to determine the best configurations of the hybrid system in terms of energy, economical, and environmental performances.

The result of this study showed that this hybrid system is a feasible choice for space conditioning for cooling–heating houses: Annual energy saving is about 15.21 × 10

6

MWh for 900,000 rural houses during the period 2010–2014. This energy corresponds to the equivalent of 42.12 × 10

5

oil barrels.

Mounir Aksas, Fouad Khaldi, Rima Zouagri

Hydropower and Ocean Energy

Frontmatter

24. Study on Tandem Configuration of a Flapping Tidal Stream Generator

So far, most tidal stream generators have been developed in three types: a horizontal axis turbine, a vertical axis turbine, and a flapping-type hydrofoil. The first two are operated by one-way rotation, but the last one is oscillated. The flapping system inspired by nature has attracted researchers due to its eco-friendly characteristics, applicability to shallow water, and nonconventional oscillating movement.

In this study, we propose a flapping tidal steam generator of a mirror-type dual configuration, and the effects of the configuration on their performance are investigated through the experimental analysis in a towing tank and numerical analysis by computational fluid dynamics simulation. Throughout the numerical and experimental studies, we found that the rear system in the dual configuration can extract power close to that of the front system with a short distance between them such as two chords and an optimum phase difference, 90°.

Jihoon Kim, Tuyen Quang Le, Jin Hwan Ko, Jin-Soon Park, Kwang-Soo Lee

25. An Economic Approach for the Design of Small Hydropower Converter

The worldwide use of hydropower potential of huge dams, weirs and waterfalls is significant—these energy sources have almost been exploited. What remains are the small waters, with low flow rates and the use of low potential in remote areas for decentralised electricity supply. This small hydropower in the range of a few kilowatts in the European and global market did not attract much attention in recent years.

Based on the European project HYLOW (the EU-Project HYLOW lasted from 2008 to 2012. Partners from five European countries took part; hydropower converters for very low head differences), the following idea has been developed: to combine various technical solutions for the use of water currents of low potential under economic and environmental optimal conditions. All relevant data were analysed and finally prepared for an interactive planning tool.

Jana Hadler, Klaus Broekel

26. Identifying Promising Wave Energy Converter Technologies

The exploitation of wave energy is in the early stages of development. Like the development of wind energy during the first half of the twentieth century, there is currently no standard system for the commercial extraction of wave energy. This creates both an opportunity and challenge for developers and investors. An opportunity, because it is likely that significant IP remains to be developed, with its associated rewards, and a challenge, because it is not yet clear which fundamental method(s) of exploitation will become dominant in the future.

Currently, it is possible to identify at least five fundamentally different types of wave energy converters, and within each one of these categories there are typically many variations resulting in over a 100 different wave energy converter technologies being developed. Undoubtedly, the developers of each technology believe that they have a winning concept and in addition have some evidence to support this view; unfortunately, it is likely that the vast majority of these developers will be disappointed. For wave energy to reach commercial viability, it will be necessary to accurately identify promising wave energy technologies.

This chapter investigates the reasons why such a large range of technologies is currently being supported and developed. This investigation centres on identifying the particular assumptions, views and perceptions that may be held by technology stakeholders and how these factors may influence wave energy converter design to both the benefit and detriment of the technology and industry. In addition, it includes further analysis of how these factors may be related to both the hydrodynamics and economics of wave energy converters. The chapter concludes with a graphical organisation of wave energy converter technologies that illustrates their fundamental development characteristics and supports the identification of promising technologies.

Matt Folley, Trevor Whittaker

27. Optimal Operation Control of Hydrokineticbased Hybrid Systems

This chapter develops a mathematical programming model to optimize the operation of a hybrid energy system consisting of a hydrokinetic, photovoltaic, wind system, a battery bank, and diesel generator. The optimization approach is aimed at minimizing the cost function subject to the availability of renewable resources, total load energy requirements, as well as the diesel generator and the battery operational constraints. Furthermore, the mathematical models of all other components of hybrid, the proposed system, and the optimization control algorithm is also developed. The main purpose of the control algorithm proposed here is to minimize the use of the diesel generator in the electricity generation process, while maximizing the use of the hydrokinetic system and other available renewable energy sources. For simulation purpose, hourly water velocity, solar irradiation, wind data, and load demand data have been collected and used as an input data. The economic analysis has resulted in the calculation of optimized daily operation cost of the proposed hybrid system in summer and winter conditions. The obtained results represent also a helpful tool for energy planners and justify the consideration of hydrokinetic-based hybrid energy systems more seriously.

Kanzumba Kusakana, Herman Jacobus Vermaak, Bubele Papy Numbi

28. Experimental and Numerical Investigation of Blade Angle Variation on a Counter-Rotating Tidal Current Turbine

Importance of renewable energy has become paramount due to its perennial source and no adverse environmental impact. Ocean is one of the major source of renewable energy where the sun’s energy is converted into various natural phenomenon. Southwestern sea in particular, in Korea, has large range of tidal currents with potential for tidal current power generation. Tidal power has great potential for future power and electricity generation because of the massive size of the oceans. The major benefit of tidal power and difference from most renewable energy sources is that it is independent of seasons and weather, that is, it is always constant which makes power generation predictable and makes tidal power a reliable energy source. Horizontal-axis-type turbine appears to be the most technologically and economically viable option for the generation of tidal power. Several studies have shown that single-rotor turbines can obtain a theoretical maximum power coefficient of 59.3 %, whereas dual rotor can obtain a maximum of 64- %. Hence, with the optimization of counter-rotating turbines, more power can be obtained than the single-rotor turbines.

Previous studies focus on the performance analysis of the turbine with the variation of distance between the blades. This chapter primarily concentrates on the investigation of the performance analysis and power output of a counter-rotating current turbine by the variation of blade angles by both computational fluid dynamics (CFD) simulation and experiments. Numerical simulations were performed using a commercial finite volume method solver, ANSYS CFX ver.13.0. Experiments were conducted in the water tank with a vertically circulating water channel in the laboratory of Korea Maritime and Ocean University (KMOU) to validate the numerical results. Several experiments were conducted with the fixed front blade angle and varying the rear blade angle and vice versa at various water flow rate. Surface streamlines, torque, total power output, power coefficient (

C

p

) etc., were characterized and compared for CFD and experimental cases. The results obtained find good agreement with each other.

Lee Nak-Joong, Kim In-Chul, Hyun Beom-Soo, Lee Young-Ho

29. Challenge to Use Small Hydropower by Contrarotating Small Hydro Turbine

Small hydropower generation is alternative energy, and there is a significant potential for a small hydro turbine. Small hydropower facilities that generate about 100–1000 kW have spread widely; however, it causes environmental destructions by a foundation construction and a set up of a draft tube. On the other hand, there are a lot of places that can generate about 100 W–1 kW (pico-hydropower) in agricultural water and a small stream. Efficiency of small hydro turbines is lower than that of large ones, and it can be used in wide flow rates range. Then, there are demands for small hydro turbines to keep high performance in wide flow rates range. Therefore, we adopted contra-rotating rotors, which could be expected to achieve high performance. In this study, a significant compact hydro turbine is named as a small hydro turbine. Final goal on this study is development of a small hydro turbine-like electrical goods, which has high portability and makes an effective use of the unused small hydropower energy resource.

In this research, we selected some places in Tokushima Prefecture in Japan, where a small hydropower could be generated, and conducted field tests of head, flow rate and water quality. Then, it was found that it was necessary to develop a small hydro turbine that could generate electricity in wide flow rates range because the small hydropower potential was different at each place. Therefore, we designed and manufactured an experimental apparatus to clarify the performance of our proposed contra-rotating small hydro turbine and investigated flow condition at the inlet of each front and rear rotor by the numerical analysis. Furthermore, the circumferential velocity distributions downstream of the rear rotor were also clarified.

Toru Shigemitsu, Junichiro Fukutomi, Chihiro Tanaka

30. Site Implementation of a Low-Head Pico-Hydro Turgo Turbine

This chapter discusses how to integrate a 1.3-kW low-head Turgo turbine into existing water infrastructure. The proposed scalable system is formed by connecting a number of identical Turgo turbine units at the same site or nearby to form an off-grid network. Three types of existing water infrastructure are considered applicable for hydropower integration: irrigation canals, reservoirs and weirs. Designs for the civil works for the low-head Turgo turbine integrated into these structures are given, and the costs of construction are estimated. Integrating the Turgo unit into these existing water structures is shown, in theory, to be cost-effective, especially in developing countries, with civil works and installation costs greatly reduced.

Samuel J. Williamson, Julian D. Booker, Bernard H. Stark

31. Design of a Linear Electrical Machine for a Wave Generation System in the Maltese Waters

This research concerns the design of an electrical machine that shall be implemented on a wave energy converter (WEC). Analysis of the available wave data and optimisation of the WEC were carried out so as to design the optimum system that will interact efficiently with the conditions of the selected location. The electrical model was designed for wave heights and periods that yielded the maximum power throughout the year. The initial finite element simulations were undertaken on the design of a four-pole tubular permanent magnet (PM) linear synchronous machine. The performance of the system was optimised for a wave height and period of 3 m and 6 s, respectively. The capacity of the linear generator was set at 15 kVA and the dimensions of the WEC (floating point absorber) were determined accordingly through the application of a simplified model for predicting the coupled dynamic response of the absorber and the linear generator. It was necessary for the electrical machine to yield good performance even when operating under the slower and most common waves. Thus, an 8-pole and a 16-pole tubular linear PM machine were also simulated, and their performance was compared. Through this analysis, the 16-pole design resulted in the best performance, especially at low speeds. Simulations were initially compared at fixed speed but were later simulated with variable speed conditions so as to represent more accurately the wave’s motion and monitor the power generator performance at variable loadings.

Xuereb Annalise, Spiteri Staines Cyril, Sant Tonio, Mulè Stagno Luciano

32. Modelling Tidal Stream Turbines

The transient behaviour of the sea and the rotation of a turbine rotor can result in high asymmetric loadings, which are transmitted to the drive shaft. A turbine mounted on a circular stanchion has been used to highlight the effects of introducing more realistic boundary conditions, over a rotational cycle of the turbine. The consequences on the turbine’s performance characteristics and crucial structural loading are shown. The position of the turbine relative to the support structure and its alignment to the flow direction can have significant temporal hydrodynamic and structural effects. Depending on their wavelength, waves can also have a significant effect on the overall design decisions and placement of devices. Thrust loading and bending moments applied to the drive shaft can be of the order of hundreds of kN and kNm, respectively. This leads to the need to not only size the drive shaft and bearings to account for axisymmetric thrust but also consider large asymmetric loads.

Knowledge of the flow regime can allow the designers to evaluate material selection for components (i.e. for blades, etc.) and incorporate some deformation capability of the turbine blades to increase the power output and potentially alleviate some of the stress distribution through key structural points, that is, drive shaft, bearing connectors, etc. The resulting data can then be used to estimate component life via fatigue prediction.

This chapter includes a multi-physics approach to modelling tidal energy devices and the potential for modelling to inform device condition monitoring.

Sarah Tatum, Carwyn Frost, Daphne O’Doherty, Allan Mason-Jones, Tim O’Doherty

33. Experimental Validation of Gap Leakage Flow Models in Archimedes Screw Generators

Archimedes screw generators (ASGs) are a form of microhydro power generation that is increasingly being adopted as an alternative renewable energy source. ASGs operate efficiently, even as head approaches zero. A small gap must always exist between the trough and edge of the rotating screw flights to allow screw rotation. This leads to two categories of flow within the screw: the primary flow remains between the helical flights and causes screw rotation, while a secondary leakage flow occurs through the gaps at the screw edges. A high gap leakage flow reduces efficiency because this flow effectively bypasses the working parts of the screw and is lost. An accurate gap leakage model is an essential component of any ASG design model. Current gap leakage models are based on experience with Archimedes screw pumps or are derived from models assuming quasi-static flow through an opening. This experimental study measured the actual leakage flow in an operating laboratory-scale ASG. The fill heights within the buckets were measured using high-speed photography and used to determine bucket volume and therefore non-gap flow. The gap flow is determined based on the difference between the measured total flow through the system and the computed non-gap flow based on the measured fill height and screw speed. The uncertainty of the gap flow is relatively high, since it is calculated based on the difference between two variables with similar magnitude, one of which is calculated based on other measurements. The existing gap flow models did not accurately predict the experimental results. Gap flow was found to be dependent on screw rotation speed, with highest gap flows occurring at intermediate screw rotation speeds. Gap flow reduces to zero as screw rotation speed approaches the maximum possible speed. There is significant uncertainty in the existing gap flow models, and gap flow models constitute one of the largest sources of uncertainty when modeling the performance of ASGs.

Andrew Kozyn, William D. Lubitz

Low-Energy Architecture

Frontmatter

34. Double- or Single-Skin Façades for Low-Carbon Office Refurbishments in the UK: A Comparative Case Study

In the UK, 75 % of non-domestic buildings will still exist in 2050, and the reduction of their emissions represents a major challenge for the UK government to meet the greenhouse gases (GHG) target. There is a growing tendency towards the use of double-skin façades (DSFs) for office refurbishments in Europe. In renovations, a DSF consists of an external glazed skin added in front of the primary building envelope and separated from it by an air cavity. DSFs have the potential to act as a thermal buffer in winter and enhance the performance of natural ventilation in summer, thus potentially reducing the energy consumption for heating and cooling in buildings.

Limited knowledge exists about DSFs for office refurbishments and, more specifically, the literature lacks comparisons between this technology and high-spec single-skin refurbishments. A case study has therefore been selected to address this gap and compare the performances of the two technologies. This chapter reports findings from the study of a cellular office building of the University of Brighton that is currently undergoing a major refurbishment. The case study is analysed with three scenarios: the building as it was, as it will be once the refurbishment is completed and as it could have been with a DSF. Detailed modelling and related energy figures are achieved by means of building energy simulation tools and compared against energy benchmarks.

Results show that DSFs are a viable option for refurbishing existing office buildings. The reduction of energy consumption with the double skin outweighs that achieved with the single-skin refurbishment. Additionally, comfort analyses for all the scenarios considered showed that the risk of overheating with the double-skin façade could be avoided by the use of shading devices to make sure that the energy reduction is not at the expense of the building users’ comfort. This study contributes towards deepening and broadening the knowledge about performances of DSFs within a refurbishment context and their potential advantages over high-spec single-skin alternatives.

Francesco Pomponi, Poorang A.E. Piroozfar

35. Architectural Factors Influenced on Physical Environment in Atrium

In the atrium of public buildings, the physical environment is determined by architectural features in various ways; therefore, an integrated consideration of the overall physical environment is important. The aim of this chapter is to find out the common factors, which influence the daylighting, acoustics, natural ventilation, and thermal environment from the viewpoint of architectural design. Based on a systematic examination and analysis of previous studies in various aspects of physical environment, different effects of material properties, atrium geometry, atrium shape, roof structure, and adjoining spaces on the daylighting, acoustics, natural ventilation, and thermal environment have been revealed. Consequently, common factors which have influenced on two or more aspects of physical environment have been identified, along with their tendency of influence. It is expected that the results would help to optimize, at the early design stage, the physical environment.

Wei Zhao, Jian Kang, Hong Jin

36. Numerical Simulation Analysis on Wind Environment of Traditional Village Courtyard in Severe Cold Regions

Outdoor wind environment has become markedly worse in recent years during winter in severe cold regions of China. The subject of the study is wind environment of the courtyard, which is an important part of rural housing and village life in China, and the quality of the wind environment, in a way, affects the using comfort of the residential indoor and outdoor thermal environment in winter. This chapter applies the computational fluid dynamics (CFD) software to simulate the wind distribution characteristics of seven cases, which have different courtyard orientation, scale, building arrangement, and the height and materials of fences. Then the design strategies are put forward which can effectively avoid the adverse effects of cold wind in winter of severe cold regions.

Xinyu Zhang, Hong Jin, Xu Dong

37. Energy Saving and Emission Analysis via Lighting Retrofitting in a Large-Scale Hospital: Case Study in Malaysia

A field study on energy efficiency by lighting retrofitting has been carried out in one of the large-scale hospitals in Malaysia. The main objectives of this study were to find energy and cost savings after light-emitting diode (LED) tubes replacement in the hospital as well as the emission reduction and payback period time. The results have showed that, by applying this strategy, the energy cost saving will be almost US $ 2 million after 3 years with more than 5000 t of CO

2

reduction per year as well as 2.9 years is resulted as payback period time.

S Moghimi, F Azizpour, C. H Lim, E Salleh, S Mat, K Sopian

38. The Effect of Wind Velocity and Night Natural Ventilation on the Inside Air Temperature in Passive Cooling Ventilation in Arid Zones

The effect of wind velocity and night natural ventilation in lowering the inside daytime air temperature in passive cooling in arid zones were investigated by numerical calculations and experimental means for different values of air change flow rate due to infiltrations and natural ventilation and different wind speed. The numerical calculations based on the inside outside air temperature, wind speed, cracks, and openings dimensions to determine the volume of air change per hour.

The experimental model was a test cell with the door facing north and the window in the opposite side facing south, the volume of the model was 9 m

3

. The calculated and measured results show that 1.8 volume per hour of air change flow rate and 2 m/s wind speed show a high concordance between calculated and measured inside air temperature and can lower the inside air temperature by 3–4 °C compared to non-ventilated test cell [1].

H. Bencheikh

39. The Building Energy Consumption and Outdoor Design Conditions of Severe Cold Regions Based on Climate Change

Climate change and its effects is a topic that attracts the attention of human beings all over the world. In recent years, the extreme climate changes frequently occurring in China’s severe cold regions have led to the increase in building energy consumption and decrease in the winter indoor thermal comfort. This chapter selects rural dwellings as the research object, and based on the meteorological data of Harbin in 63 years, it applies the frequency distribution analysis to obtain the extreme temperature values under different recurrence intervals; meanwhile, taking these values as the outdoor design conditions, this study simulates and compares the building energy consumption in different conditions, so as to reveal the effects of climate change on building energy consumption of heating in winter and provide the quantitative basis for the energy-saving optimization design of rural dwellings in severe cold regions.

Teng Shao, Hong Jin

40. Low-Energy Architecture: Cuban Contradictions

Cuba has a very strong tradition in low-energy architecture along the history. The aborigine architecture was a clever answer to the local environmental conditions, which have been continued by the vernacular and rural ones. Despite that the colonial cities followed the Mediterranean model, they were progressively transformed for a better adaptation to the climatic conditions. Even the modern architecture developed during the first half of the twentieth century, recovered the best former traditions, combined with the new aesthetic, generating a highly qualified built environment.

During the past half a century, research works have been systematically carried out, focused on the evaluation of architectural and urban solutions according to climatic and energy behavior. These issues were included in the curricula of architecture and urbanism since the 1960s, and several standards have been elaborated during the past 30 years to propose principles and regulations to take advantage of daylight and ventilation, as well as to reduce the thermal load in buildings.

However, most of the contemporary Cuban architecture does not apply the research results, taking into account the standards, or following the tradition of the Cuban passive low-energy architecture, but on the contrary, it use to copy foreign models coming from developed countries with cold climates. The results of study cases are presented in the chapter in order to evaluate the architectural solutions, trying to discuss the causes of the wrong practice.

Dania González Couret

41. Towards Nearly Zero-Energy Buildings in 2020 in the Netherlands

The aim of this article is to give information and insight in nearly zero-energy building (nZEB) developments in the Netherlands that will occur in the near future and what consequences these developments have for buildings, in particular for building services. In 2020, all newly built buildings have to comply with the nZEB regulation with an energy performance coefficient ≈ 0. To support the future policy on energy performance improvements, this study provides a roadmap towards nZEBs with a technical and financial feasibility framework. Life-cycle cost calculations, also beyond cost optimality, are essential for determining the Dutch nZEB definition, because these determine if the energy efficient measures are profitable, cost-effective, and can be implemented in the building law.

Kristian Gvozdenovic, Wim Maassen, Wim Zeiler

42. How to Reach for the Necessary Synergy Between Architecture and Engineering

New strong demands for a more sustainable built environment led to a more complex design process. The different expertise of engineers must be used more effectively by architects especially in the conceptual design phase to reach for new solutions. To support diverse multidisciplinary building design teams, a supportive design method was developed in cooperation with the Dutch professional organizations of architects and consulting engineers. It helps architects and engineers with their new role in the conceptual design phase as it enables to structure each perspective on the design task as well as to structure the available domain knowledge by using morphological charts (MC) and morphological overviews. After testing the method in workshops as part of a training program in industry, the design method was transferred and applied at the department of architecture for master students for their multidisciplinary master project integral design (ID). In the past 9 years, master projects ID were held and there was a continuous development to optimize the cooperation between architects and engineers. The research showed that it is possible to engage engineers and let other disciplines learn from them within the conceptual building design phase, which makes it easier to achieve nearly zero-energy buildings.

Wim Zeiler

43. Study of the Aeraulic Flows in the Building of the Valve Halls Mandarins, France

The site object of this work connects Sellindge, England, and Les Mandarins by a National Grid and Réseau de Electricity Transmission Network, usually known as RTE, to allow the transfer of high-voltage electricity from England to France and vice versa. The aim of the project studied is the renovation of two converter stations having a capacity of 2 × 1000 MW high-voltage direct current (HVDC) with an electric potential of 270 KV, and the link connecting the Great Britain (GB) and French transmission systems was attributed to AREVA T&D (PC 8892 A AREVA, IFA 2000 Valves & Controls Replacement Project Sellindge and Les, 2009). After this, the electricity is produced at a power station, where it will be distributed to the customers.

This study concerns the building of the valve halls mandarins, France. The valves have to be replaced because the existing valves discharge all of their heat into the halls, whereas the new valves will have water cooling systems to remove most of the heat at source. However, some heat will still be discharged into the halls, so the ventilation systems must be changed to assure the requirements of the new valves and to maintain the halls at the suitable conditions.

The produced electricity is transferred towards the outside via the overhead conductors which operate at high voltage and connect the valves with the bushings. The maximum air temperature around bushings must be lower than 40 °C. The high degree of temperature is not supported by the bushings and will be damaged.

N. Laaroussi, L-V. Bénet, F. Lacroux, M. Garoum

44. Experimental and Theoretical Study for the Performance of New Local Thermal Insulation in Iraqi Building

Iraq is located in a hot-arid region, where the hot summer season is very long and the ambient temperature is about 50 °C, while in the winter the temperature is about 10 °C. Therefore, cooling of buildings needs A/C system, which consumes 60 % of the total electricity supplied to residential building. So, there is really a need to minimize the energy consumption by enhancing the performance of Iraqi buildings. To minimize the effect of the environment upon the building, one must look for methods to increase the thermal resistance of walls and roof. This chapter deals with the experimental and theoretical study using new local thermal insulation on walls and roof with an air gap. This study takes into consideration several parameters like ambient temperature, solar radiation, orientation, and duration. The results of the work give good indication that using this insulating system in residential building has great effect on the energy consumed. Also, the results reveal that a system with sufficient insulation can save the annual cooling load for the room by 6 MW and that the indoor temperature can reach 35 °C, while the ambient temperature is about 45 °C.

Ghanim Kadhim Abdulsada, Tawfeeq Wasmi M. Salih

45. Simulation-Based Optimization for Energy and Buildings

This chapter presents implementations of simulation-based optimization by giving two examples for finding optimum values of design/decision parameters in the building envelope, building heating/cooling systems, and energy systems. In addition, the features of the multi-objective building performance optimization program (

MOBO

®) are presented. MOBO is a new generic freeware able to handle single- and multi-objective optimization problems including continuous and/or discrete variables. It can be coupled to many simulation programs and has a library of different types of algorithms (evolutionary, deterministic, hybrid, exhaustive, and random).

It is concluded that simulation-based optimization is an efficient method for finding optimum values of design/decision variables in the building envelope, heating/cooling systems, and energy generation systems. While an exhaustive search method will need a huge number of simulations to find optimal solutions, the optimization algorithm will need reasonable time and number of simulations to find comparable solutions. It can be used in finding optimal solutions for the fulfillment of zero, net- or nearly-zero energy/emission buildings, where minimization of energy emissions and cost and maximization of indoor air quality are the targets.

Ala Hasan, Matti Palonen, Mohamed Hamdy

46. Low-Energy Earth–Air Heat Exchanger Cooling System for Buildings in Hot and Humid Malaysia

This chapter presents an extended exploration of the performance of low-energy earth–air heat exchanger (EAHE) cooling in hot and humid Malaysia from the published work of Sanusi (2013). The increasing demand of air-conditioning for cooling purposes motivates this investigation in search for better cooling alternatives. The passive technology, where soil underground was used as a heat sink to produce cooler air, has yet to be investigated further in hot and humid countries. This work, the passive technology, is tested by carrying out two interconnected field investigations: soil temperature measurement and the earth pipe cooling experiment for 1 year. In 1 year, soil temperature distribution at 1 m depth fluctuates, influenced by the different seasons in a year. However, the soil at 1 m depth is cooler than deeper soil during the wet season. Therefore, for investigating the EAHE cooling performance for 1 year, the pipe was buried at 1 m depth at the same test site. A significant temperature drop was found in the 1-m-depth-buried pipe: up to 6.3 and 8.6 °C, respective to the seasons of the year. Thermal comfort of air temperature at the buried pipe outlet was analyzed with Khedari thermal comfort chart, and the result has shown that the buried pipe outlet air temperatures are within the range of thermal comfort conditions for hot/humid countries. This study has showed a potential of earth pipe cooling technology in providing low-energy cooling in buildings in Malaysia.

Aliyah N. Z Sanusi, Li Shao, Nila I Keumala

47. Analysis of Passive Solar House to Improve the Indoor Thermal Environment in Winter in Lhasa, China

The application of solar heating in winter was studied based on the solar resources in Lhasa area of China. The difference of indoor thermal environment and residents’ thermal sensation vote between the passive solar house and typical Tibetan residential buildings was compared in winter in Lhasa, through the methods of subjective questionnaire and actual test. The results show that the winter indoor thermal environment in passive solar houses is better than that in typical Tibetan residential house. First, the residents’ comfort satisfaction in solar houses was higher than that in typical Tibetan residential houses. Second, the indoor temperature range, which was accepted by more than 80 % of the residents ranged from 11.3 to 22.5 ℃ in passive solar houses, while the range was from 13.6 to 23 ℃ in typical Tibetan residential buildings. Third, the measured winter thermal neutral temperature in passive solar houses was 16.44 ℃, 1 ℃ lower than typical Tibetan residential buildings. At the same time, the temperature in passive solar houses is higher than in the traditional Tibetan residences, but it changes greatly during the day and night. This chapter shows the effectiveness of passive solar houses in improving the indoor thermal comfort by using solar energy in winter in Lhasa. The research findings have an important role in promoting the use of passive solar house or other energy-saving buildings in Lhasa and the Qinghai–Tibetan Plateau area.

Ming Zhang, Wei Yu, Baizhan Li

48. Building Energy Index and Students’ Perceived Performance in Public University Buildings

Numerous studies have shown that students’ learning experience is closely associated with the physical comfort level of their teaching and learning environment. The different strategies or allocation of air-conditioning, mechanical ventilation (ACMV) and lighting systems contribute greatly to the energy performances in the buildings. This study explores the relationship between electricity consumption of the academic buildings of a public university in an urban context and its students’ perceived performance. It seeks to find the answer patterns from unsuspected subjects; whether there is a difference between a lower energy-use building and a higher energy-use building. To achieve the objective, the study adopts the quantitative method of assessing students’ perceived performance through questionnaire survey. The questionnaires, adopted from Building Use Studies, UK, were distributed randomly through convenience sampling to students from two academic buildings in the campus. Both buildings were selected through purposive sampling method with specific inclusion and exclusion criteria. Subsequently, power and energy logger was installed into the same buildings to monitor electricity consumption at specific intervals. For comparison, building energy index (BEI) for each building was calculated. The study found that the building that scored higher in students’ performance, also has higher calculated BEI. As control for indoor comfort account for more than half of the total electricity consumption, the result suggested that electricity consumption influences students’ performance positively. The study also revealed that both buildings’ calculated BEI were lower than recommended by many standards. This suggests that these buildings have extremely high potential of achieving green building status. If executed properly, the university campus, which equates the size of a small city, may achieve green campus status sooner than expected and may lead others in the flagship project towards a low-carbon university campus.

S. N. N. Syed Yahya, A. R. M. Ariffin, Muhammad Azzam Ismail

49. Energy-Efficient Refurbishment of Existing Buildings: A Multiple Case Study of Terraced Family Housing

The building sector in Europe consumes an estimated 40 % of the total energy. It is well established that the reduction of building energy consumption necessitates energy-efficient renovation of the existing buildings. To achieve this objective, primarily, it is necessary to document the existing building stock.

This chapter focuses on multiple case studies of terraced family houses. Representative terraced family houses from different chronological periods, which are typical and representative of the national residential building stock typologies, act as model buildings and are used for demonstrating the energy performance and the potential energy savings resulting from energy conservation measures (ECMs) and interventions made on both the building envelope and the heat supply systems.

Successful strategies and techniques toward reducing the energy consumption and CO

2

emissions are simulated using the Tabula.xls tool, which is an excel spreadsheet algorithm-based tool. A database with the appropriate information concerning the energy-related characteristics of the terraced family housing has been developed. The research aims to fill in the gap of the current knowledge and the building typologies and it could be a useful instrument to facilitate the energy performance assessment of the building stock and to highlight the potential of renewable energy use in terraced family housing.

D.K. Serghides, N. Saboohi, T. Koutra, M.C. Katafygiotou, M. Markides

50. Low-Energy Architecture: From Theory to Design

This introduction projects the potential application of bioclimatic design interwoven with the objective of energy efficiency and the utilization of renewable energy resources for indoor comfort. This is, nowadays, of particular interest for all countries, since architecture is currently influenced beyond the usual functional, cultural and technological constraints by the incidence of rapid urban development and huge tourist inflows. This often results to standardized “international architecture” with high-technology services and catastrophic ecological and cultural consequences. Sadly, these international designs rely mostly on mechanical means, with high consumption of energy, ignoring the local tradition of climatic design, which respects the environment and reflects the thread of continuity, coherence and local flavour. Bioclimatic architecture considers the building totally from the stage of its inception as a place of energy exchange between the indoor and the external environment, natural and climatic. It considers the building as a living organism; a dynamic structure which utilizes the beneficial climatic parameters (solar radiation for winter, sea breezes for summer) whilst avoiding the adverse climatic effects (cold winds for winter, solar radiation for summer).

It is precisely the approach to this challenge of bioclimatic, energy-efficient architecture, posed to every designer as the coordinator of multiple considerations that is to be presented and discussed during this introduction. The main heating and cooling strategies are outlined and their adoption in the design process is approached in four stages from site planning, orientation and shape, layout and envelope of the building. These aspects are illustrated with the “Bioclimatic Designs for the Student Housing of the New University Campus of Cyprus”, for which the author was the bioclimatic consultant, and the first phase of buildings for the University of Cyprus (Architect A. Kyprianou & Associates), to indicate how bioclimatic techniques address the problems of thermal and optical control.

Despina K. Serghides

51. Development of a Luminous Efficacy Model Using Ground and Satellite-Based Data from the Tropics

In this work, a global luminous efficacy model was developed. The formulation of the model was based on global illuminance and global irradiance measured at four tropical sites in Thailand. The model expresses luminous efficacy as an empirical function of aerosol optical depth, precipitable water, satellite-derived cloud index and cosine of solar zenith angle. The aerosol optical depth and precipitable water were obtained from Aerosol Robotic Network (AERONET) of NASA, and cloud index was derived from multifunctional transport satellite (MTSAT)-1R satellite. The model coefficients were calculated using a 4-year period of hourly data (2007–2010), and the model was validated against an independent data set for 2011. The model predicted well the global illuminance with a root mean square difference (RMSD) of 3.6 % and a mean bias difference (MBD) of 0.3 %. In addition, the model was compared favourably with most existing models when tested against this independent data set.

Rungrat Wattan, Serm Janjai

52. Investigation on the Existing Circumstances and Contributing Factors of Thermal Environment of Rural Housings in Severe Cold Zones of China in Winter

In order to improve the dwelling conditions and living standards of peasants in severe cold zones of China, a comprehensive and in-depth survey is taken on the residential buildings in severe cold zones. Through a combination of field survey and questionnaire, a number of investigations are conducted including the existing status of residential buildings in terms of house types, spatial arrangements, heating facility, construction levels, material and structure system, fuel consumption, and the utilization of local renewable resources as well as the economic conditions, demographic structures, and indoor thermal perceptions of peasants. The indoor thermal environment of residential buildings in winter is also measured. By investigating and summarizing the existing circumstances of thermal environment in rural housings in winter, as well as analyzing the main factors contributing to the poor indoor thermal environment, adaptive approaches are explored to lay foundations for further in-depth investigation and construction of the energy-efficient green residential buildings.

Hong Jin, Kai Chen

53. Simulation Analysis and Planning Strategies for the Wind Environment of Residential Quarter in Harbin

Currently, a residential quarter is the main form of residential buildings in China, whose surrounding microclimate, especially the wind environment, has a great impact on the living quality of residents. Based on the climate conditions of Harbin, which is located in the severe cold zone in China, this chapter selects five typical layouts of residential communities, and analyses the characters of wind environment in winter within each layout mode using Fluent software. The optimal distribution mode and planning strategies are hopefully proposed, as well as the corresponding improvement methods according to the existing problems. It is suggested that the prediction and evaluation of wind environment of residential communities should be carried on from the stage of planning and design, in order to eliminate the negative factors in time.

Ming Li, Hong Jin, Teng Shao

54. Energy Efficiency Building Codes and Green Pyramid Rating System

Three building energy codes were introduced in Egypt between 2005 and 2010. They impose mandatory energy performance requirements for residential, commercial, and governmental buildings. Another code was presented (2013) to improve the indoor air quality and ventilation requirements and system. This chapter addresses the current states and the potential of energy efficiency, renewable energy, and green buildings to reduce the dependence on the fossil fuel. These codes were the base line for green building code. The first edition of the Green Pyramid Rating System was published in December 2010. The Green Pyramid Rating System is a national environmental rating system for buildings. It provides definitive criteria by which the environmental credentials of buildings can be evaluated, and the buildings themselves can be rated. The Egyptian government has an interest in promoting green buildings as part of Egyptian policies of overall sustainable development. The Housing and Building Research Centre (HBRC) established the Egyptian Green Building Council (EGBC) at the beginning of 2009. Another code is under preparation for Green Hotel Rating System in Egypt to improve the Egyptian Touristic sector. The essence of this chapter is to introduce the efforts being undertaken by Egypt to improve the quality of life and highlight the barriers and overcome the challenges that Egypt faces, and these are summarized in three main parameters, namely, energy, water, and housing.

George Bassili Hanna

55. Simulation Comparison Between Natural and Hybrid Ventilation by Fans at Nighttime for Severe Hot Climate (Aswan, Egypt)

The computer simulation measures the effect of ceiling and wall fans in decreasing air temperature during nighttime. The indoor temperature exceeds the thermal comfort through the overheated period in Aswan. A high time lag of envelope in the daytime increases the indoor temperature at nighttime. As a result, the indoor temperature becomes higher than the outdoor temperature at nighttime of the overheated period.

The simulation study consists of three models according to ventilation conditions (types). The first model that depends only on cross ventilation is called the natural ventilation model. The second model is the hybrid ventilation that consists of natural ventilation (cross ventilation) and mechanical ventilation (ceiling fan). The third model uses wall (side) fan instead of the ceiling fan. The boundary conditions are placed according to the weather conditions in Aswan in the overheated period (July).

Simulation results of hybrid ventilation models decreased the indoor temperature from 2 to 4 °C. The wall (side)—average indoor air velocity in the case of wall fan is 1 m/s—fan is better than the ceiling fan—average indoor air velocity in the case of ceiling fan is 0.86 m/s) according to decreasing indoor temperature (4 °C), and airflow is well distributed inside the room at the sitting level.

A. Rizk, A. El-Deberky, Nabil M Guirguis

56. Green Building and Energy Saving

The colored glass has great effects to prevent the solar heat gains and consequences to minimize the air-conditioning loads which mean low energy consumption. In this chapter, the effect of glass color on the energy saving in a flat was carried out in two climate zones Alexandria and Aswan in Egypt to know the suitable colored glass for each zone. The investigation was done using the computational fluid dynamics (CFD) called “Visual DOE” which is one of the famous energy programs. The results indicated that the light-colored glass type has a great effect on the energy saving in building.

Mahmoud A Hassan, Nabil M Guirguis

57. Energy Savings and Environmental Benefits from Solar Window Film for Buildings in Kurdistan of Iraq

The advances in thin film coatings for window glass products provide a means of substantially reducing heat gain without proportionally reducing daylight transmittance.

Households in Kurdistan of Iraq pay rather high electricity bills in summer due to the excessive use of fans, evaporative coolers and air-conditioners, since the solar radiation intensity in Kurdistan of Iraq (e.g. Duhok city) at midnoon in summer season exceeds 1000 W/m

2

, and the air temperature goes as high as 45 °C. Also, the rise in the use of air-conditioning in residential buildings is having a serious impact on the environment. This could lead to high levels of carbon dioxide (CO

2

) and other greenhouse gas (GHG) emissions. Now environmental concern grows, a more-efficient energy conversion and utilization technologies become cost-effective. Saving money on energy bills is attractive to businesses, industries and individuals alike. Regulations and standards worldwide tend to embody detailed energy analysis of buildings.

In this chapter, two wooden cabinets were built as a building simulation. Measurements were made for two wooden cabinets, one with solar control film coating on the window glass and the other without. The results of an experimental investigation aimed at assessing the performance of thin film windows in the wooden cabinets are presented. The work is performed under real weather conditions. The data are integrated with spectrophotometric measurements.

In order to decrease the solar heat gain, window films may be a good choice against the solar heat gain caused by the windows in the building. The findings showed that the solar film coating could cut down energy expenditures for air-conditioned buildings. Concerning the environmental benefits, the reduction of CO

2

emission by reducing the electrical energy consumption using window film was calculated. Briefly, in this study, it was found that, the window film works smarter and greener to save energy costs.

Kamil M. Yousif

58. Research on Daylighting Introduction of Commercial Buildings in Different Climate Zone of China

This chapter chose Beijing, Harbin, Kunming, Shanghai, and Shenzhen, the key cities of different climate zones in China and studied the lighting energy-saving effect of daylight in large commercial buildings. Based on interior Pedestrian Street that is a typical composition pattern, this study uses the DAYSIM analysis to affect the trends of different daylighting system on energy saving of artificial lighting in different opening ratio, different orientation and different climate zone.

Hong Jin, Xin-xin Li

59. Reducing Canadian Greenhouse Energy Costs Using Highly Insulating Glazing

This study explores the potential to significantly reduce heating costs in northern climates by adding additional layers and types of glazing to simulate greenhouse-like structures with highly insulating roofs that still allow appreciable light transmission. Representative typical meteorological year (TMY) data are used with a one-dimensional multilayer heat transfer model to explore the potential of insulated glazing panels for increasing solar gain. The model was validated against interior temperature and exterior weather data collected at a small unheated greenhouse in winter conditions. It was found that it is possible to reduce winter heating energy costs by using thicker-than-normal insulated glazing, although in practice, energy savings will be offset by added costs of the insulated glazing and additional measures would be needed to minimize summer heat gain. However, the potential for reducing winter heating energy costs suggests potential for highly insulating, semitransparent cladding.

William David Lubitz

60. Self-Sufficient Prefabricated Modular Housing: Passive Systems Integrated

In recent years, the construction of efficient and sustainable housing has experienced a significant development, and it is thought that in the near future these criteria will be required in most new constructions. In this context, the architectural project includes the bioclimatic strategies to promote the energy saving and comfort. Spatial organization, zoning, and variability of form factor will be considered. By means of balancing plant-volume model, it can be adapted to a particular climate and remake the popular architectural tradition with nowadays technology (e.g., the Andalusian patio). The materials used should have fast regeneration, low environmental impact, and high durability. Ceramic or wood promote passive conditioning. Besides, they can be combined with new components such as phase change material that increases the thermal inertia. Its use to current constructive systems can be adapted in a flexible way to different places or uses. This research is based on the housing prototype “Patio 2.12” presented to the international competition Solar Decathlon Europe 2012, awarded with the second prize in the general ranking, the first prize in energy efficiency and energy balance, and the second prize in sustainability and innovation. Different architectural models are experienced that integrate the use of solar photovoltaics (PV) and “passive systems”: The technological patio like a “buffer space” is an intermediate damper space of outdoor climate conditions that allows the control of solar incidence and the generation of drafts. It is constructed in two layers: the first one is glazed and also mobile, in order to open it or close it, and the second one consists of adjustable blades that provide shade. In winter, it causes a greenhouse effect, and during summer, it favors ventilation. Passive cooling by evapotranspiration or “jug effect” can cause the envelope to become an “active material”; in this case, the ceramic skin is breathable and incorporates an irrigation system that humidifies the ceramic pieces. When the water gets evaporated, the system absorbs the energy, cooling the cavity wall; the cool air is then recirculated into rooms through automated gates. Passive ventilation by solar chimney works by heating a volcanic rock on the roof, which generates a convection current that ventilates the module. It is not only to acclimatize the inside of the room but also to regulate the air quality. This chapter presents a study of an “open industrialized system” that comes from a spatial and constructive prefabricated modular system, based on compatible and interchangeable elements. The production in factory and the dry construction system used are advisable from a sustainable point of view because the quantity of waste generated during the manufacturing, assembly, and disassembly processes is minimized. Due to the utilization of supports over the ground, it is a construction without trace on landscape. Reuse of the living module responds to the economic sustainability claimed by nowadays society. The innovations presented can be applied in social housing, substandard housing, rehabilitation, eco-touristic housing, and the exportation of manufactured housing emergency.

Alberto García Marín, Jorge Barrios Corpa, Javier Terrados Cepeda, Juan de la Casa Higueras, Jorge Aguilera Tejero

61. The Road to Integrated Design Process of Net-Zero Energy Solar House

An integrated design process

encourages holistic collaboration of the design team to optimize solutions in an iterative development of a building design. This chapter discusses the design process of a net-zero energy solar-powered house developed for the 2013 solar decathlon competition to promote high-performance design while using traditional passive strategies. The University of North Carolina Charlotte (UNC Charlotte) entry tries to effectively integrate building systems’ components to minimize energy consumption while optimizing comfort. To that end, each component delivers multiple functions.

Being part of a large and varied team, seeing a project from the preliminary design phase to construction and commissioning, the students were provided a true multidisciplinary hands-on opportunity. The opportunity proved to strengthen their technical skills, acquired in the regular curriculum, via integration of theoretical knowledge and practical experience. Moreover, organized in a multidisciplinary format, students were then able to share their strengths across disciplines and contribute to a synthesis of process and product. The greatest learning experience for the students occurred in the

integrated design process

—across engineering disciplines, architecture, and business—the student team members also learned how to raise funds, procure materials and construction equipment, and how to interact with one another.

This chapter reports a way of effectively designing and iteratively modeling process to inform the design decisions

.

Mona Azarbayjani, Ben Futrell, Valentina Cecchi

62. Describing Native Architectural Features of Kandovan, a Sustainable Village with Rock Architecture

The purpose of the present chapter is to investigate the unique features of Kandovan as well as its rural elements playing a role in the traditional texture of the village as sustainable elements. The village is located 62 km from Tabriz, Iran, in a region with moderate mountain climate. The village of Kandovan is a specimen of the most primitive type of human life and its coexistence with nature. The village texture consists of a series of pointed cones with manmade and natural cavities emerging on the surface. These cones have sporadically extended over the steep mountain skirts toward the peak of the mountain in a condensed and scattered manner. The building of the houses in Kandovan are of the rock-made architecture and date back to the seventh century (in the Hijri solar calendar) and in cases to even as early as pre-Islamic eras.

The rocky architecture of Kandovan represents man’s struggle to harness and tame the nature to satisfy his needs. The structure and texture of the cone-shaped habitats of the village, made of INEMBERITE and ALTHER, formed with the passing of time by the combination of the volcanic materials from the Sahand with the mud resulting from flood-causing rainfalls. The residential space in the Kandovan village is carved off the stone mass and rock Karans (rock-shells) create a firm crust around the space like a body, protecting the residents from natural phenomena such as rain, snow, wind, cold, and heat. In addition, the shape of the cones and their positioning has a substantial effect on increasing a sense of comfort and convenience for the residents through regulating environmental conditions like heat, cold, humidity, and light. The village Kandovan is listed as one of the three rocky villages of the world, the other two being the Kappadokia in Turky and Dakota in the USA. Kandovan is different from other rocky villages, in that life is still present and the residents of the village still continue to live their day-to-day life with the natural features of the village without making fundamental changes in the structure of their habitats.

The methodology of the present chapter is based on library research method and field observations, and describes and analyzes the structural and architectural elements existing as sustainable elements in the texture of the village. Notable among the elements are the integrated and interconnected rural texture; interior and exterior design of the houses; access means; apparatus; ventilation; cooling and heating system; materials, types, and typology of the Karans; and the rocky architecture. Kandovan, with its high potential in aptly using sustainable architecture may be fit as a model for various sustainable structures around the world.

Navid Nahi, Maryam Singery

63. Investigating the Effect of Climatic Factors on the Spatial Structure of Old Texture of Yazd City: A Specimen of a Sustainable Urban Texture

Sixty-one percent of Iran’s area in located in arid and super-arid climate. Possessing 2.1 % of lands, 4.2 % desert phenomena without vegetation, and 8.3 % desert regions of the world, Iran is one the hottest and driest countries. Most of the regions in Iran are faced with severe limitations in vegetation and water resources. Nevertheless, such areas have housed several residences, since a long time ago, where man has dwelled because of necessity. The adverse climate of these regions has always caused numerous difficulties for the living of the residents and the residents have had to come up with solutions to resist and have ultimately managed to reduce the adverse irritating climatic aspects, providing the conditions for comfort and peace. The major difficulties that has evoked the residents of hot and dry regions to seek solutions include intense summer heat, severe winter cold, burning sunlight, high day and low night time temperatures in the environment, sandstorm blows full of dust, water shortage, vegetation scarcity, air dryness, and earthquake threat.

Among the habitats that have managed to keep their residents safe against the harsh climatic conditions and overcome the above mentioned difficulties, is the city of Yazd. Yazd is ranked the first as an adobe city and the second, next to Venice, Italy, as a historical city in the world. Being located in the heart of Iranian deserts with a long history, Yazd has won the title “Desert Capital.” The ancient texture of the city, an exemplar of a live desert city, may provide a model for sustainable urban designs, as the old texture of the city is still in optimal use after several years and at times, it has even demonstrated a better performance over the modern texture of the city which enjoys the technology and materials of the day. It has also been optimally responding to the needs of the residents. The integrated architecture of Yazd has taken advantage of all the available potentials in every single structural element in the texture city and buildings including the materials, forms, space planning, and has provided environmental comfort.

The purpose of the present research is to investigate the effect of climatic factors on the spatial structure of the ancient texture of Yazd. The study is carried out in a descriptive-analytic design and has described and analyzed the urban elements that serve as sustainable elements in the traditional texture of the city through library (review) and field observations. Namely among the elements are the integrated and connected urban texture, independent urban neighborhoods, optimal orientation toward sun, conducting and controlling winds to provide thermal comfort, semiopen squares, narrow passages with tall walls, typology and form of the roof covers, Sabats, courtyards, the application of native materials, and additional elements that play a significant role in stabilizing the city structure.

Navid Nahi, Maryam Singery

64. Enable Environmental Policies for Eco-Industrial Growth: A Voluntary Government Tool for Local Productive Areas in Tuscany (Italy)

The Regional Government of Tuscany in Italy, approved a regional regulation to establish a new voluntary approach at the regional level for the development of “industrial parks.” For the first time in European environmental and industrial policies, the “industrial ecology” principles are applied with an approach that allows an area to achieve an official environmental certification. In the literature, we find mainly experiences that rely on command and control policies to implement industrial symbiosis concepts. As opposed to those practices, this chapter presents and analyzes a new method to stimulate the creation and dissemination of eco-industrial parks based on a voluntary approach.

The “ecologically equipped productive area” has been introduced in the Italian Legislative Order by the D.Lgs. n. 112/1998, Bassanini law, which expects that “Italian Regions discipline, with their own laws, industrial areas and ecologically equipped areas, provided with infrastructures and systems necessary to ensure the protection of the health, safety and environment”.

Ecologically equipped productive areas have to be planned, realized, and managed on the basis of “ecoefficiency” criteria, in order to ensure an integrated system of management of environmental aspects, reduction and prevention of air, water, and soil pollution, the protection of the health and safety as well as a widespread environmental improvement of territory. The question is to organize the productive site so as to favor the individual settled firms on realizing their own environmental objectives, both economically and technically.

In the case under discussion, the certification scheme is fully voluntary and the certification process is coordinated by a Regional Authority; Regional law of Tuscany (L.R. Toscana n. 61 22/12/2003) establishes priority objective to develop a new concept of industrial areas, characterized by quality management systems and infrastructures for protection of health, safety, and environment, obtained by local authorities assessment methods that integrate economical, social, and environmental issues.

This chapter describes the criteria and requirements that an area must meet in order to obtain the qualification, and the roles and responsibilities of all involved actors. The criteria, inspired by industrial symbiosis concepts, are related to planning, infrastructure, and management-related issues.

Paola Gallo

65. Smart Envelope for Nearly Zero Energy Schools. The Case Study of Vallisneri Secondary School in Lucca

The research SE*NZES analyses the evolution of smart façade systems in the area of design and industrial production, in order to investigate the technological, functional and qualitative standards of dynamic façades and to evaluate the energy performance of the school building envelope as a dynamic system that interacts with the indoor and outdoor environment. The study focuses on dynamic envelopes for the refurbishment of the school buildings, analysing the evolution of façade systems in terms of building construction, energy and structural performance and durability.

The research project has been developed with the aim of spreading the research topics identified by Cordis and European Directives 2010/31 and 2013/27, developing a smart façade system, achieving the reduction of the energy requirement in the building sector by 2020 and realizing zero energy public buildings.

The refurbishment of the existing school building stock requires ground-breaking strategies in order to meet targets for improved indoor comfort in the classrooms and to reduce energy use and greenhouse gas emissions. One of the most important components to be addressed with an innovative approach is the building envelope, which has to develop into an active rather than a passive element, fulfilling more functions than just the separation of the outer space from the interior with insulation.

The concept of the adaptable envelope is twofold. On the one hand, it has been designed to accommodate further modifications (such as future renovation or technology upgrades). On the other hand, the envelope is able to adapt to a dynamic and intricate environment by measuring and processing multisource information (e.g. outdoor and indoor environment conditions, occupancy, behaviour of users and envelope performance) in order to respond to the building occupant’s instructions and evolving environmental conditions at an appropriate time and to an appropriate extent.

The main topic of research has been to develop an innovative and smart façade system that will be possible to integrate in the retrofitting of existing school buildings. In this smart envelope, it will be possible to integrate

Advanced materials or technologies for energy generation and storage

Smart and performance insulation materials

Reflecting materials and cool coatings

Adaptable innovative precast solutions

Materials with enhanced acoustic properties

Materials with improved fire resistance

Automated blinds or movable sun barriers with interrelated issues of summer overheating, air-tightness and natural light use

Innovative sensing systems to control and optimize the real-time performance of the envelope

In this chapter, we introduce the characteristics of smart façade for school buildings, analysing the technological solutions and the energy performance to reduce energy needs of this type of building. We will be observing, in particular, the case study of the refurbishment of one school building: the “Vallisneri Secondary School in Lucca”, where we have designed and built an innovative façade system. The project focused on the adoption of a precast façade in order to control solar radiation in summer and heat loss in winter, reduce the heat losses between the opaque envelopes and increase the natural ventilation inside the school building.

Rosa Romano

66. A Comparison of Computational Simulation and Physical Measurement of Solar Radiation and Photovoltaic Outputs for Residential Dwellings

By 2016, new residential buildings in the UK will have to be ‘net zero carbon’ to comply with proposed changes to Part L of the Government’s Building Regulations. Approved document Part L of the Building Regulations requires energy use and generation, and the resulting carbon emissions, to be quantified using the Government’s standard assessment procedure (SAP) model. To achieve a zero carbon dwelling, on-site renewable technologies must usually be incorporated into the design. Since the introduction of the feed-in tariff (FIT), in April 2010, photovoltaic (PV) systems have been seen as one of the most cost effective methods of achieving the higher levels of the code for sustainable homes (CfSH), the route to meet zero carbon emissions in domestic buildings. The quantification of energy generation for CfSH certification, comes directly from the SAP model, where the methodology used to justify the use of PV systems is crude in its prediction of shading and utilises simplified rules-of-thumb to predict how shading will affect energy generation. This chapter compares the prediction methods currently available to designers (SAP) against real data collected on live building projects in South West London. Included in this study is the physical measurement of solar radiation where PV panels will be installed at a later date, together with the measured outputs from two recent domestic PV installations that are benefiting from the FIT initiative. For both of these, in terms of solar radiation and electricity production, comparisons are made between actual measurements and predicted results. The results of this study show that the methodology provided in the SAP 2005 and 2009 models for determining the available energy at inverter output (kWh/year) for solar PV systems is crude and inaccurate, particularly in locations where there is significant shading from external obstructions, and particularly where an evaluation of the overshading is required. The SAP methodology for quantifying the shading coefficient is crude and there are little guideline provided. A novel technique for quantifying overshading has been tested in this study and the results indicate that a more robust method is required. The methodology being proposed is in line with more comprehensive approaches that have been adopted by other organisations, in particular new guidelines and methodologies published and recommended by the microgeneration certification scheme (MCS). Proposals by the BRE for improvements to the SAP 2012 model, for the calculation of incident solar radiation, and the energy generated by a solar PV system, are generally positive but the determination of overshading in any particular location remains crude and difficult to quantify.

Stephen Pretlove, Patrick R. Osborne

67. Courtyards: Optimum Use as Means of Providing Daylight into Adjacent Zones

The aim of the study is to investigate daylighting performance in spaces adjacent to courtyards in the climatic conditions of the UAE (latitude 25°N longitude 55°E). Two cases were simulated mainly to understand how the space generally performed in terms of lighting performance. The two cases comprised of the same universal adjacent space but in one case the courtyard size was doubled while maintaining the same height for both cases. The Desktop RADIANCE 2.0 program (DR) was used to evaluate the lighting performance of the adjacent space under clear sky conditions. Horizontal illuminance levels, diversity and uniformity of illuminance, and Spatial Daylight Autonomy (sDA) were the lighting parameters used. These parameters were compared to the standard values or recommended ranges specified in lighting codes and handbooks such as the Chartered Institution of Building Services Engineers (CIBSE) and the Illuminating Engineering Society of North America (IESNA). The study revealed that although both models provided sufficient amount of illuminance level into the space it failed in the other aspect of diversity and uniformity, some suggestions were highlighted to be tested at a later stage.

Maitha M. Bin Dalmouk, Khaled A. Al-Sallal

68. Earth Construction: The Mechanical Properties of Adobe with the Addition of Laponite

The contribution describes testing of compression strength, flexural strength and abrasion resistance of

adobe

made up of soil, water and sand (AS), soil, water, sand and straw (ASP), soil, water, sand and laponite nanoparticles (ASN). Embodied energy in materials presents an increasingly high percentage of the energy spent in the whole life cycle of a building. The same applies for carbon dioxide (CO

2

). Therefore, the development of new sustainable construction materials with lower embodied energy and lower CO

2

emissions is needed.

The use in construction of the brick made from soil, water and sand or straw, called

adobe

, boasts a millenary tradition and in recent years there has been renewed interest in a material readily available and ecofriendly. Earth is a building material that is able to act perfectly in balance with the environment: earth lends itself to achievements accessible to any manufacturing organization and is also a resource available in most geographical contexts. It allows one to manufacture products suited to pursue energy conservation and comfort in different climatic regions. The use of

adobe

presents: reduction of embodied energy and CO

2

at component level; improvement of insulation properties; reduction of the total costs compared to existing solutions.

Francesca Scalisi, Cesare Sposito

69. The Development of Renewable Energy Applications in Buildings in Greece During The Last Decade

Greece is a country rich in renewable energy sources (RES). A consequence of this is that the country performs well in the field of renewable energy applications. The share of renewable energies in the national production of primary energy is over 20 %. The bulk of the energy generated by the country’s RES is consumed in the building sector and covers mainly heating and hot water production needs. The forms of renewable energy that are found in applications in Greek buildings include solar, wind, geothermal and biomass energy. The quantity of energy that these energy sources represent increased by more than 70 % during the last decade for which statistics are available (2002–2012). This work presents and attempts to interpret the data for the development of renewable energy applications in buildings in Greece during this decade.

Nikos Papamanolis

70. Preliminary Results Concerning the Thermal Comfort in a Romanian Passive House

Energy saving is a recognized priority worldwide. The goal for the construction industry is to conceive and operate buildings with low energy consumption. However, sometimes energy saving can cause discomfort to the occupants. A field survey was done in a naturally ventilated passive office building during summer. Comfort parameters were measured and occupants were distributed comfort questionnaires consisting of questions related to their thermal sensation and preference.

This chapter compares the experimental results with the subjective responses. It analyzes the relationship between thermal preference and sensation of the occupants which depends on the floor where the occupants work. The survey results are compared with the comfort ASHRAE standard 55 and are in agreement with the standard.

Ruxandra Crutescu, Ioana Udrea, Ilinca Nastase, Cristiana Croitoru, Viorel Badescu

71. Towards a Comprehensive Approach to Sustainable Urban Planning: Integrated Estimation of Housing Electricity Consumption and Photovoltaic Generation Potential Using the web-based framework iGUESS®

Cities play a key role in the mitigation of carbon emission, however there is a need for comprehensive tools able to support sustainable urban planning. The Smart City Energy platform powered by the web-based framework iGUESS® is a geospatial platform for decision support giving access to a series of calculation modules and providing visualization of energy related maps for cities.

This chapter presents an exemplary application of iGUESS for the combined assessment of housing electricity consumption and photovoltaic (PV) generation potential at the urban scale. The study provided relevant results for a test case study in Rotterdam city (Netherlands) for the integration of PV and assessment of the energy potential.

Alessio Mastrucci, Christian Braun, Olivier Baume, Francesca Stazi, Ulrich Leopold

72. Energy-Efficient Lighting by LED

Light emitting diodes (LED) is the light source of the future because of energy efficiency, performance, and life-time. Due to their small dimension and high flux many innovative solutions for non-glare and controlled light distribution are developed for various applications. This chapter deals with a joint R&D project (R&D project, funded 2012–14 by AiF: Entwicklung flacher, durchsichtiger und gleichzeitig selbst-leuchtender Elemente nach dem Prinzip der Lichtleitung mit gezielter Lichtauskopplung durch Mikrostrukturen. Research team: Green Building R&D, JO GmbH & CO. KG., RIF Institut für Forschung und Transfer, Temicon GmbH, TU Dortmund Faculty of Electro- and Information Technology) for edge lit and highly transparent light guiding plates with controlled single-sided light emission. The transparency allows for looking through the plate and is not affected by the specific micro-structure for light emission on one surface of the light guide.

The work plan, including optimization of microstructures by ray-tracing simulation, development of manufacturing technology for large scale production, and system design for different applications, is carried out by an integrated team from university and industry. The main objectives are economic manufacturing technologies, high quality and low energy lighting and architectural system integration.

Helmut F. O. Mueller, Francesco Sasso

Wind Energy

Frontmatter

73. Power System Performance of Offshore Wind in the UK in 2030

At least 34 % of the UK’s power must come from renewable energy sources to meet planned European Union targets in 2030. Wind power will provide the majority of this renewable electricity with an estimated 36 GW offshore and 21 GW onshore. The success of the Crown Estate’s leasing rounds 1 and 2 in offshore wind has meant the UK is now one of the world leaders in offshore wind power development. Leasing round 3 will see offshore wind in the UK surpass 36 GW of installed capacity. This is a significant increase from the current installed offshore wind capacity of 3.6 GW. This research investigates the power system performance of offshore wind power in the UK in 2030.

P. Higgins, A. M. Foley

74. Testing Operation and Control Functions of Wind Power Plant Control System by Hardware in-the-loop Simulation

The grid system operators in many countries require a grid code for a wind power generation system (WPGS) or a wind power plant (WPP). For satisfying the grid code, a wind power plant control system (WPPCS) is needed because it requires the possibility for controlling active and reactive power in point of common coupling (PCC). The WPPCS should have the ability to send out set points to all WPGSs, and each WPGS must be able to ensure set points from the WPPCS. This chapter presents a performance analysis method without a real WPP to evaluate a WPPCS using hardware-in-the-loop simulation (HILS) using a real-time digital simulator (RTDS). A HILS method for a WPPCS using a RTDS is presented, and performance of the WPPCS is analyzed. A 50-MW WPP which includes 5 MW WPGS is modeled and analyzed in RSCAD/RTDS. A prototype WPPCS is developed to control and operate a 50-MW class WPP, which is connected to the RTDS through the Distributed Network Protocol (DNP)3.0. The HILS results show the proposed method can be effectively utilized to validate control functions of WPPCSs.

Jong Yul Kim, Gyeong Hun Kim, Jin-Hong Jeon, Seul Ki Kim, Eung Sang Kim

75. Blade Element Momentum Theory and CFD Modeling as a Tool for Optimizing Wind Turbine Blade Design

The present chapter focuses on the comparison of the capabilities of Blade Element Momentum Theory (BEMT) in relation to computational fluid dynamics (CFD) modeling as a tool for the design and performance optimization of a horizontal axial wind turbine (HAWT).

A generated blade is examined in different scales by BEMT with the use of the QBlade software. The same wind turbine blade design was then incorporated in a detailed 3D CFD model (in ANSYS CFX). Computations were performed and the results were compared to the ones produced with the BEMT method.

For the CFD modeling, a National Advisory Committee for Aeronautics (NACA) profile was initially validated through a two-dimensional analysis and flow field investigation regarding lift and drag coefficients for a variety of angles of attack (AoA). For computation reasons, a rotating domain was applied. The domain is discretized into 4,320,733 elements, most of which are tetrahedral, creating 781,582 nodes. An extra inflation layer is used on the turbine boundary and mesh density is higher in that vicinity.

After the validation of the two-dimensional analysis, the wind turbine blade design was incorporated in a detailed 3D CFD model and computations were performed and compared to the ones of the BEMT method. Detailed transition formulas were applied and compared and a mesh independent solution was achieved. Furthermore, pressure and velocity distribution on the blade are analyzed and Cp graphs were produced.

The shear stress transport (SST) turbulence model capability to simulate the flow around an airfoil in the pro stall region was verified, while, the angle of attack at which stall begins could also be predicted using CFD modeling.

The study revealed the superior performance and advantages of CFD modeling in relation to BEMT since CFD can take into account the 3D effects of actual flow around a turbine blade which cannot be obtained by BEMT methodology.

K. Dogan, G. Martinopoulos

76. Integration of Wind Energy in Power System—Modelling of a Market Oriented Energy Concept

Regenerative energy sources play a leading role in future energy generation. In this chapter, some commercialisation scenarios concerning offshore wind farms are discussed. The focus is set on energy-exchange trading combined with offering control reserve (secondary control reserve (SCR) or minute reserve (MR)) or offering only control reserve without participating in energy exchange trading. In other words, some alternative ways of operating a wind farm compared to Renewable Energy Act (EEG) commercialisation (feed-in tariff) is presented. First, a brief introduction is given, then the so-called power-to-gas storage system (P2G) is introduced, later, technical as well as economical results are presented and finally, a brief look into the future is made.

Yassin Bouyraaman, Jörg Bendfeld, Philipp Breymann, Stefan Krauter

77. Design and Experimental Validation of Thick Airfoils for Large Wind Turbines

In this chapter, two new airfoils with thickness to chord ratios of 30 and 36 % are presented, which were designed with an objective of good aerodynamic and structural features. Airfoil design is based on a direct method using shape perturbation function. The optimization algorithm is coupled with the viscous/inviscid flow solver XFOIL.

Wind tunnel tests for both airfoils were performed in the LM Wind Power low speed wind tunnel at Reynolds numbers of 1.5–6 million and various surface conditions. The results from the experiment confirm that the optimization algorithm is suited for airfoil design and the designed airfoils have top performance.

Iva Hrgovan, Wen Zhong Shen, Wei Jun Zhu, Jesper Madsen, Rolf Hansen

78. A Novel Topology for Enhancing the Low-Voltage Ride-Through Capability for Grid Connected Wind Turbine Generators

Energy shortage and environmental pollution have led to the increasing demand of using renewable sources for electricity production. Currently, power generation from wind energy systems (WES) is of global significance and will continue to grow during the coming years leading to concerns about power system stability where wind farms replace conventional generating technologies that use fossil fuels as the primary energy source. One of these concerns is low-voltage ride-through (LVRT). In this chapter, a novel topology based on the use of magnetic amplifier for enhancing the low voltage ride through capability for grid connected permanent magnet synchronous generators (PMSG).

R. A. Ibrahim, M. S. Hamad, Y. G. Dessouky, B. W. Williams

79. Conceptual Design of Airborne Wind Turbines

Airborne wind turbines (AWT) are a novel conceptual approach of enhancing the existing capabilities of capturing wind energy. AWT generate power from winds at altitudes of up to 1500 m, using a tethered structure with on board turbines, through a range of lift production methods. The chosen path for conceptual design was with a lighter than air (LTA) structure combined with a current small-capacity wind turbine. The chosen design approach was to use airship design principles, once the materials, gas, tether and turbine had either been designed or selected. Development of the design was carried out using a computational fluid dynamics (CFD) package, ANSYS CFX, to analyse the aerodynamic characteristics of the structure’s shape. The design of AWT is still in the infancy phase and has numerous associated issues, with Civil Aviation Authority (CAA) regulations regarding airspace and tethering of balloons, and environmental conditions and impact. Through this research, the intention is to present further AWT designs, which utilise readily available small-capacity wind turbines, paving the way for additional research to be conducted.

Hossein Mirzaii, Liam Griggs

80. Wind Shear Assessment Using Wind LiDAR Profiler and Sonic 3D Anemometer for Wind Energy Applications—Preliminary Results

This chapter presents an assessment of wind shear up to 400 m at a coastal location. The vertical structure, temporal variations and influence of atmospheric stability were investigated. The results show four important findings using light detection and ranging (LiDAR) and dimensionless shear analysis. First, the top of surface layer can be considered around 200 m. Second, the wind speed decreases with height above 240 m from 11:00 to 16:00 local time. Third, the atmosphere can be considered to be stable from 10:00 to 14:00 and unstable from 19:00 to 01:00 according to the Monin–Obukhov similarity theory (MOST) theory. Fourth, the wind speed remains almost constant, with a height of up to 300 m in the first part of the night when the dimensionless shear is low. In addition, measurements taken with a sonic 3D anemometer confirmed the excellent correlation between the turbulent fluxes and the dimensionless shear. For strong winds, when the friction velocity is high, dimensionless shear varies almost linearly and at low friction velocity, it varies exponentially.

Yoshiaki Sakagami, Pedro A. A. Santos, Reinaldo Haas, Júlio C. Passos, Frederico F. Taves

81. Atmospheric Stability Effects on Small Wind Turbine Power Collection in a Complex Terrain

The power performance assessment of a small wind turbine (SWT) based on atmospheric stability is reported herein. An experimental setup was used to study a 2.1 kW SWT in a suburban environment, where 1 Hz power collection data and 20 Hz turbulent flux measurements were obtained. The dataset consists of 4287 h of raw data covering a 6-month period. The measured International Electrotechnical Commission-based (IEC) power curve shows an average performance 30 % above the manufacturer’s curve, but with decreasing power output close to the rated wind speed. Values relating power collection increase at low wind speeds with high turbulence levels concur with previous studies. The Obukhov length was used as a stability parameter, and stability-dependent power curves were compared with the measured average. Above 8 m/s, unstable conditions were predominant and evidenced the decreasing power tendency, where turbulence intensity (TI) was unable to give consistent results. The results reported in this chapter validate an approach suitable for SWT assessment using a physical parameter as a classification criterion, which better explains the power collection behaviour close to rated conditions.

Pedro A. A. Santos, Yoshiaki Sakagami, Reinaldo Haas, Júlio C. Passos, Frederico F. Taves

82. Robust Design of Savonius Wind Turbine

The Savonius wind turbine, a class of vertical axis wind turbine (VAWT), is simple and provides a better cost-benefit ratio. It works on the principle of differential drag and is effective in rooftop and ground mounting. Despite the advantages of Savonius wind rotors, they are not preferred due to their low aerodynamic performance levels. In order to address this, several experimental and numerical studies have been carried out in recent years. The primary aim of this work is to provide a simple methodology for the robust optimal design of the Savonius wind turbine. In the parameter design stage, the performance of the turbine is maximized using the traditional Taguchi method. An L

27

orthogonal array is used considering five factors of three levels each, which affect

C

p

. Wind speed is considered to be the noise factor. Signal-noise ratio (SNR) metric is used to find the optimal settings for robust design. The aerodynamic performance of the turbine is investigated through dynamic computational fluid dynamics (CFD) models of the design sets. The numerical models used for the simulations are also discussed.

Vishaal Dhamotharan, Ranjana Meena, Piyush Jadhav, Palaniappan Ramu, K. Arul Prakash

83. Coupling Floating Wind Turbines with Large- Scale Air-Conditioning Systems Through Deep Sea Water Pumping: Case Studies of System Performance in European Deep Waters

This chapter presents a novel concept for utilising offshore-floating wind turbines to concurrently exploit cold deep sea water (DSW) for large-scale cooling applications, as well as electricity production. This concept utilises wind turbine-driven pumps that extract cold DSW and pump it across a high-pressure pipeline to a land-based hydroelectric power station coupled to a centralised air-conditioning (AC) unit of a district cooling system. The wind-driven intermittent supply of cold water exiting the hydroelectric station is diverted to the condenser of the unit and mixed with sea surface water (SSW) to maintain a steady flow. The use of DSW lowers the condensation temperature of the refrigerant in the AC unit, resulting in an improved coefficient of performance for cooling conditions. This chapter investigates the potential application of the concept described above to four European deep offshore sites located in the Mediterranean Sea: the Greek Islands, Malta, the South of France and Spain. The numerical model used to compute the energy yield characteristics at these sites assumes a single offshore wind turbine system with modules for the wind turbine–pump assembly, the deep sea thermocline formations and the frictional/thermal losses across the pipeline and the hydroelectric turbine. Another module is dedicated to the thermodynamic refrigeration cycle for the AC unit. The study confirmed that although the losses incurred in transmitting energy from offshore wind turbines through the DSW pipeline are larger than those for conventional wind turbines relying on electrical cables, such losses may be partially or fully compensated for by the superior performance of the wind turbine-driven hydraulic pumps at high wind speeds and by the energy savings incurred in AC plants through DSW utilisation. The latter savings were found to be the highest for the Greek Islands due to favourable wind conditions also prevailing during the hot summer months.

Tonio Sant, Robert N. Farrugia, David Arroyo López-Carro

84. Denmark Wind Energy Programme

In this chapter, a summary of some ongoing wind energy projects in Denmark is given. The research topics comprise computational model development, wind turbine (WT) design, low-noise airfoil and blade design, control device development, wake modelling and wind farm layout optimization.

Wen Zhong Shen

85. Development of Realistic Demand Side Management Strategies Using Artificial Neural Networks for the Production of Informative Wind Speed Prediction Signals

Urgency to achieve large-scale integration of the stochastic wind energy production calls among others for the employment of novel solutions including energy storage, upgrade of electricity grids, and application of effective demand side management. To this end, the problem of limited wind energy integration becomes even more severe in isolated island regions, owed to the weak character of local electricity grids. For this purpose, the current study emphasizes on the need for the production of adequately reliable forecasting wind speed signals that can, in turn, inform the development of appropriate energy, and especially demand side management strategies. In this context, we use artificial neural networks (ANN) and provide prediction of wind speed for three different island locations of the Aegean Sea, evaluating the wind speed signals for 1–10 h ahead. Our results demonstrate that wind speed predictions up to even 3 h ahead can sufficiently inform the development of appropriate energy management strategies, designating the potential of ANNs in the field of wind speed prediction.

D. Zafirakis, K. Moustris, Ch. Maragkos, M. Stathopoulos, G. Tzanes

86. Comparative Study of Two Types of Wind Turbine Simulators for Wind Energy Conversion System

Electricity generation using wind energy is becoming the fastest growing source of renewable energy. There are several types of wind turbine simulator (WTS) or emulator for evaluation of wind turbine generators, power electronic converters, and turbine control algorithms. These WTSs have each a different purpose, and have been used to serve the purpose.

It is difficult to construct a wind farm using a conventional WTS with motor–generator (MG) set because of its cost and volume. In this chapter, a WTS composed only of a power converter without an MG set is proposed, and the two types of WTSs for a wind energy conversion system are compared.

The conventional WTS with MG set consists of two 10 kW directly coupled permanent magnet synchronous generators, a motor driver, a power converter, and a microcontroller. The microcontroller calculates wind turbine torque or rotation speed for the motor driver. However, the proposed WTS with only a full power converter and without an MG set includes a rectifier which is connected to the grid and the microcontroller. The rectifier is used instead of the generator of the wind conversion system, and just supplies electric power to the grid-connected converter. The microcontroller for only the full power converter type wind simulator simulates status values of the wind turbine.

The experimental results show the output power and the rotating speed of two types of wind simulator under varied wind speed conditions. It is expected that the wind farm simulator can be designed using the proposed WTS. The results of the chapter can effectively be employed to design or construct wind farm simulators for testing wind farm controllers.

Gyeong-Hun Kim, Jin-Hong Jeon, Jong-Yul Kim, Jong-Bo Ahn, Chulsang Hwang, Eung-Sang Kim

87. Wind Power Is the Last to Be Stored

Pumped water storage had been widely used on power systems well before the advent of wind power. The economics rely on arbitrage between cheap night-time electricity and expensive daytime generation: a commercial store must buy electricity when it is cheap and sell when it is dear. As there is no solar power at night, this means solar power cannot be economically stored on a power system.

Pumped water storage systems can also help to cope with power system fluctuations but these control and balancing activities are quite distinct from energy storage. Even though the basic physical processes underlying any electrical engineering plant on a power system, such as capacitors and inductances, involve storage of energy, it would be wholly misleading to describe them as being for power system energy storage.

That would be like calling a school bus “a means of transporting fuel”. A description that will be literally correct for a physicist may be totally misleading in a practical engineering context.

Storage cannot be economically installed in association with wind. Providing capacity for times of base load has little value because the maximum amount of spare plant is available then. Wind power is mainly for saving fuel, not providing capacity, and round-trip losses will only waste some of the fuel that has already been saved if such electricity is stored and regenerated. A store must buy at night and generate during the day to be economical, but wind power may need to generate at any time around the clock and sometimes all around the clock for many days on end. So wind power is contractually incompatible with storage.

Nevertheless, with storage already in place for other reasons, it might be thought that when a store is taking in power (typically during times of base load) and the wind happens to be blowing, wind is as likely as any other sort of power to be stored. Not so. The power being stored is that plant which would be switched off if storage ceased (e.g. because the store failed or filled). On a well-run power system which always uses the cheapest power generation available at any time, that will be the dearest power online. With no fuel cost, wind is always the cheapest online and so it will never be the one to be switched off. So wind is never stored unless the cheapest is also the dearest, and wind is the only plant still generating. Then wind is the last to be stored.

Donald Swift-Hook

Backmatter

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