Exergy for A Better Environment and Improved Sustainability 2

In Hassi Messaoud’s oil industry, the systems which are water based (WBM) are generally used for drilling in the first phase. For the rest of the well, the oil mud systems are employed (OBM). In the field of oil exploration, panoply of chemical products is employed in the drilling fluid formulation. These components of different natures and whose toxicity and biodegradability are of ill-defined parameters are, however, thrown into nature. In addition to the hydrocarbon (HC, such as diesel) which is a major constituent of oil-based mud, we also can notice spills as well as a variety of other products and additives on the drilling sites. These wastes are usually stored in places called (crud wastes). These may cause major problems to the ecosystem. To treat these wastes, we have considered two methods which are solidification/stabilization (chemical) and thermal. So that we can evaluate the techniques of treatment, a series of analyses are performed on dozens of specimens of wastes before treatment. After that, on the basis of our analyses of wastes, we opted for diagnostic treatments of pollution before and after solidification and stabilization. Finally, we have done some analyses before and after the thermal treatment to check the efficiency of the methods followed in the study.

Following pollution incidents involving toxic elements such as nickel, huge efforts aiming at purification of industrial wastewater prior to discharge into the natural environment have been made.In order to contribute to the achievement of this environmental protection goal, we have studied the removal of Ni2+ from industrial wastewaters using bentonite-type clay, a natural and locally abundant adsorbent. In addition, a comparative study of Ni removal capacity using a dead bacterium Streptomyces rimosus biomass was undertaken.The results of our investigations are given in terms of adsorption isotherms, rate constants, and estimated global diffusion coefficients. A batch adsorption kinetic experiment revealed that nickel adsorption onto these materials—bentonite and biomass—was well represented by the pseudo-second-order kinetic model. The adsorption isotherm data well fitted with the linearized Langmuir model.

In this work, a comparative study and evaluation of CO₂ capture process using monoethanolamine (MEA) and diethanoamine (DEA) is reported. Ten different process configurations from a power plant are simulated and compared in terms of the total equivalent work and the reboiler duty. Process flow sheet modifications present a good performance with respect to the reduction of energy consumption. It is carried out with a 0.38–4.61% of reduction for MEA and 0.27–4.5% for DEA. Furthermore, a detailed analysis is presented to study the effect of four significant parameters in capture process, including various temperature, pressure, and concentration. This analysis presents the influence of the interaction between solvent and process, which is essential in post-combustion process design to make optimization strategy.

The aim of this paper is to investigate and compare the effects of n-butanol/diesel fuel blends (nBDFBs) and n-butanol fumigation (nBF) on the engine performance and exhaust emissions in a turbocharged automobile diesel engine. Experiments have been performed for various nBDFBs and nBF at different engine speeds and loads. For nBDFB and nBF tests, nB2, nB4, and nB6 and nBF2, nBF4, and nBF6n-butanol percentages were selected. Here, for example, nB2 and nBF2 contain 2% n-butanol and 98% diesel fuel by volume, respectively. The test results showed that smoke decreases significantly by applying both of these two methods. However, decrement ratios of smoke for fumigation method are higher than that of blend method. NO_x emission decreases for nB2, but it increases for nB4 and nB6 at selected engine speeds and loads. NO_x emission decreases generally for nBF. For nB2 and nB4, bsfc decreases slightly, but it increases for nB6. For nBF, bsfc increases at all of the test conditions. Adding n-butanol to diesel fuel becomes expensive for two methods. For nBDFBs, heat release rate (HRR) diagrams exhibit similar typical characteristic to NDF. However, for nBF, HRR shows slightly different pattern from NDF and a double peak is observed in the HRR diagram. The first peak occurs earlier than NDF and the second peak takes place later. In addition, this diagram shows that the first peak becomes larger and the second peak diminishes as n-butanol ratio is increased.

The objectives of this chapter are to measure densities of the highest methyl ester yield corn oil biodiesel and its blends with commercially available diesel fuel at different temperatures and also to develop new one- and two-dimensional models for predicting density values by using the measurements. For these objectives, first, corn oil biodiesel having the highest methyl ester content was blended with commercially available diesel fuel at the volume ratios of 5%, 10%, 15%, and 20%, and densities of each blend were measured at different temperatures of 10, 20, 30, and 40 °C by following the ISO test method. Then, some one- and two-dimensional models were fitted to the experimental data, and these models were compared with each other. According to results, among one-dimensional models, linear ρ = ρ(X) = a + bX and power ρ = ρ(T) = aTb + c ones were found to be more suitable for representing the density–biodiesel fraction in the blend and density–temperature relationship, respectively. Also, when compared with the two-dimensional model, linear with respect to X and power with respect to T, ρ = ρ(T, X) = aTb + cX, the linear surface ρ = ρ(T, X) = a + bT + cX gave a higher degree of accuracy to represent the variations of densities of the blends with respect to temperature and biodiesel fraction at the same time. Moreover, the qualities of the corn oil biodiesel and its blends was evaluated by determining other important fuel properties such as kinematic viscosity, flash point temperature, and higher heating value.

The objective of this chapter is to determine the effects of biodiesel fraction in blend (X) and temperature (T) on dynamic viscosities of the highest methyl ester content corn oil biodiesel and its blends with commercially available diesel fuel. For this objective, first, the highest methyl ester content corn oil biodiesel was produced by using potassium hydroxide (KOH) as catalyst and methanol (CH₃OH) as alcohol, and the biodiesel was blended with commercially available diesel fuel at the volume ratios of 5, 10, 15, and 20%. Then, dynamic viscosities of pure biodiesel and diesel fuel, their blends were measured at different temperatures of 10, 20, 30, and 40 °C by following DIN 53015 test methods. From the obtained experimental data, one- and two-dimensional models as a function of X or T were derived using the least square regression for estimating dynamic viscosity values of pure fuels or fuel blends. Also, these models were compared to previously published models and measurements to show their validities. According to regression analysis results, among the proposed one-dimensional models, rational ones such as μ = μ(X) = (aX + 1)/(b + cX) with minimum correlation coefficient (R) value of 0.9942 and maximum error value of 4.5976%, μ = μ(X) = (a ∙ X + 1)/(b + c ∙ X) and power ones such as μ = μ(T) = aTb + c with minimum R value of 0.9914 and maximum error value of 3.9733% better represent the dynamic viscosity–biodiesel fraction and dynamic viscosity–temperature relationship, respectively, and these models give higher accuracies for predicting viscosity values. Also, two-dimensional combination surface model including exponential and linear terms such as μ = μ(T, X) = a ∙ ebT + c ∙ edX + eX with the higher R value of 0.9952 and lower maximum error value of 3.2319% was recommended for demonstrating the variations in dynamic viscosity values with respect to biodiesel fraction and temperature simultaneously. Furthermore, the quality of the corn oil biodiesel and its blends were evaluated by determining the other important fuel properties, such as kinematic viscosity, flash point temperature, and higher heating value.

Material flow analysis is a key tool to quantify and monitor natural resource use. A very visual way to undertake such analyses representing the mineral trade of a certain nation or continent is through the well-known Sankey diagrams, in which the mineral resources that are extracted, imported, exported, recycled and consumed within the given boundaries are represented with the arrows proportional to their respective quantities. Yet Sankey diagrams alone are not sensitive to the quality of the resources as they only reflect tonnage. This issue can lead to misleading conclusions and thereby ineffective resource policies. A way to overcome this deficiency is using Grassmann diagrams instead, in which instead of tonnage the flows are represented in exergy terms, thereby accounting for the physical value of minerals. In this chapter we use the exergoecology method to evaluate mineral trade and foreign dependency in EU-28 for the 1995–2012 period. Using the year 2011 as a case study, we can see that 45.8% of the total input tonnes of minerals are imported resulting in low values of self-sufficiency (Domestic Extraction to Domestic Material Consumption ratio). With data expressed in exergy replacement costs we can better reflect the real material dependency, 0.45 for minerals and 0.41 for fossil fuels, in contrast to 0.79 and 0.52 obtained respectively when using tonnes. Analyzing 10 of the 20 minerals considered critical by the European Commission, imports represent 6.74% of the total imports while extraction represents only 3.19% of the total extraction. This external dependency leaves Europe in a delicate situation regarding fossil fuels and non-fuel mineral supply and highlights the importance of recycling and the search for alternative sources.

Adana is a major agricultural and commercial center in southern Turkey. Adana is one of the first industrialized as well as one of the most economically developed cities of Turkey. The main aim of this project is to develop a new infrastructure for integrated solid waste management for Adana Metropolitan Municipality, including Yedigöze Union. New transfer stations have been located in Yedigöze Union to transfer all collected solid wastes to Adana Metropolitan Municipality Landfill Site for recycling and disposal. All plastic materials, including medical wastes, collected from Adana Metropolitan Municipality and Yedigöze Union will be transferred to a thermal and catalytic cracking unit for producing plastic fuel. All medical wastes will be sterilized and converted to plastic fuel without any Medical Waste Sterilization Unit. Experiments have shown that plastic fuel can be blended with 10% of diesel fuel and can be used for waste collection truck without any modification.

The dissemination of heavy metals such as zinc in the environment caused a contamination of groundwater and rivers. In order to curb this phenomenon, it becomes essential to develop a method to remove these toxic materials. Among these techniques, we have adsorption on biosorbents; these materials are efficient, inexpensive, and abundant.In our study, we have adsorbed/desorbed zinc on peel of peas. From the obtained results, we learn that the elimination of zinc by our adsorbent is done by ion exchange and the substrate can be regenerated with hydrochloric acid.

Biodiesel is an ecofriendly and renewable source of energy which can be used as a sustainable alternative fuel for diesel engine. The study investigated engine performance and emission using soybean biodiesel blends with fossil diesel. The physiochemical fuel properties of the biodiesel were determined using ASTM and EN standards. The biodiesel was blended in different proportions like 5% biodiesel and 95% diesel (by volume) denoted as B5, similarly B10, B20 and B50. The biodiesel blends were tested in a multicylinder, diesel engine coupled with electromagnetic dynamometer, under ISO 8178–4 test procedure. The study found that the biodiesel blends produce less brake power, brake torque and relatively higher brake-specific fuel consumption compared with diesel fuel. However, these fuels significantly reduce exhaust gases, namely, CO, CO₂ and HC but emit a bit more NO_x compared with diesel. The reduction in emissions were different for each biodiesel blend. The study concluded that both B5 and B10 blends are the optimum blends that produce more consistent and expected results compared with other blends.

The research focus on renewable energy has become a necessity due to the ecological and environmental effects, and biofuels are one of the most effective substrate for existing fossil fuels. Indeed, the algae are presented as a potential source of biofuel with their several important advantages; they have a great deal of attention as a renewable alternative source of biomass for bioethanol production. One of the algae which has the potential to be developed as a raw material for bioethanol is Spirogyra alga. It has been demonstrated that Spirogyra species can accumulate high levels of polysaccharides and starch in their complex cell walls, which allows using it as a source of bioethanol production.In this chapter we present this research work, which addresses the development of the algal biomass in the energy field. An experimental effort was extended by converting the biomass of Spirogyra alga into ethanol; the strains used in this study were collected from a natural lake in the province of Touggourt located 180 km from the center of the city of Ouargla southeast of Algeria.

Problems of construction material oxidation/corrosion, hydrogen permeation, and embrittlement become especially important at high-pressure electrolysis. Ion implantation and magnetron sputtering application possibilities for electrocatalysts and protective coating synthesis have been numerically estimated and tested mainly for PEM electrolysis. Stability of cathode materials based on titanium has been increased up to 3–4 times with carbon and nitrogen ion implantation. In case of anode titanium materials (current collectors, bipolar plates), Pd and Pt ion implantation was used for anticorrosion and antioxidant protection. Two energy ranges were examined: 40–50 keV and 1–5 keV. The first range energy ion penetration into Ti was more than 100 nm, but the surface concentration (even at dose about 1017 ions/cm2) was rather small to protect Ti from an intensive oxidation. The surface concentration of implanted ion of the second energy range has been increased up to 20%, but the modified layer thickness was rather small for high surface layer stability. Combination of high- and low-energy implantation modes has permitted to reach rather high surface stability with a rather high lifetime (increased more than one order in model experiments) at Pt (Pd) concentrations less than 0.02 mg/cm2. For bipolar plates and current collectors of porous Ti, a combined technology based on magnetron sputtering of Pt (Pd) assisted by ion (Ar, N, O) implantation has demonstrated even more efficient results due to additional chemical and radiation surface modification but at slightly larger platinum metal loadings. Magnetron sputtering assisted by ion implantation appeared to be also rather efficient for catalyst layer synthesis for PEM and alkaline electrolyzers.

Metal pollution in the aquatic environment is among the priority environmental issues. The origin of the pollution in the rivers can be anthropogenic or natural. Eastern Black Sea region of Turkey contains important mineral deposits. The aim of this research is to determine the seasonal changes of physicochemical parameters and land-based metal levels in the Sürmene River, which is located in the eastern part of the Black Sea. Metal concentrations (Cr, Mn, Al, Co, Ni, Cu, Zn, As, Mo, Cd, Sb, Pb) were measured in water and sediment samples. It has been determined that dissolved Al, Mn and Zn concentrations in stream water are higher than 1 μg/L levels, while concentrations of other dissolved metals are lower. According to seasonal distributions, there are no statistical differences for Pb, Cd, Mo, As, Zn, Cu and Co concentrations. The concentrations of Al, Fe, Mn, Cr, Cu and Pb in sediment samples collected from Station 1 which is closer to the sea were found to be higher.

Biofuels constitute an effective alternative to existing fossil fuels, for they offer the prospect of ecological sustainability with their various advantages. Biodiesel has become one of the most important biofuels on a worldwide level; and it is synthesized by oil transesterification.In this study, the production of biodiesel is done by oil transesterification. Two types of oil are used: the first is the regular ELIO oil (edible vegetable oil composed of 20% of sunflower and 80% of soybean); the second type is the recycled oil used at most three times for frying. Some parameters characterizing these oils are determined as follows: the refractive index, the cetane number, the acid number, and the saponification number, in addition to the evaluation of density and viscosity variations at different temperatures. The characterization of the obtained products can be summarized in the determination of the acid number and the flashpoint, through the study of density and viscosity variations at different temperatures, and by infrared spectroscopy. The latter shows us that the formed biodiesels are indeed methyl esters of fatty acids. A comparison between these two types of synthesized biodiesels and the international standards has shown that the synthesized biodiesels are in conformity with the international standards.

Algeria is one of the countries of the Mediterranean basin that faces different problems related to water scarcity, deserted hydric resources, management of natural resources, and climate change as the rate of precipitation is very unstable. Water desalination is practically the unique solution for the Mediterranean countries and Middle East and North Africa region to deal with the growing water scarcity. The climate of Algeria is known for its diversity and interannual rainfall variability. However, different programs were launched and efforts are being made to find an alternative solution. Brackish and seawater desalination can provide an inexhaustible source of freshwater in coastal and semiarid areas. In Algeria, desalination plants operate using nonrenewable energy sources which require a large share of generated electricity. Desalination techniques based on membrane separation have seen a big development. They seem to be very powerful tools for the treatment and recycling of fluids for the goal of “zero waste.” This process is used for removing salt and other effluent materials from water molecules.The present work reveals the different seawater desalination facilities and demineralization plants implanted in Algeria and the major technical problems they encounter when they are operational. Reverse osmosis desalination technology is suitable in Algeria in terms of market share where membrane separation allows to couple water treatment and valorization.

Petroleum process industries are one of the most energy- and emission-intensive sectors throughout the world. There are natural gas processing plant, crude oil and condensate fractionation plant, liquefied natural gas plant, liquefied petroleum gas plant, etc. that create environmental pollution by processing and handling of petroleum products. The study critically reviewed and discussed the energy and environmental management including pollution control of petroleum process industries of Bangladesh. They produce both gaseous (process gas, waste gas, etc.) and liquid (produced water, waste oil, grease, etc.) pollutants. The study found that the liquid pollutant like waste water is more hazardous and its treatment process is highly complicated due to its higher salinity, more corrosivity and grease-containing characteristics. As part of energy management, the rational use of energy and energy flow diagram of the petroleum industry is presented. Finally, a time frame measure which can be implemented in order to save energy is outlined. The study concluded that the rational use of energy and proper environmental management are essential for achieving energy and environmental sustainability of process industries.

Knowledge of solar residential devices’ thermal performance is necessary in order to optimize their output. This requires a database of solar radiation for locations for which the system is being installed. In this regard, temperature maps are generated for a realized parabolic solar cooker using an improved solar radiation model for 48 cities in Algeria. The maps are drawn for two cases: clear and cloudy skies in winter and summer seasons, which allow comparison between cooker performances. The developed approach consists in converting the obtained results from optical simulation to thermal values based on Stefan-Boltzmann law. Experimental data for receiver temperatures and solar radiation measured at Ghardaïa city in December were used for validation. It was found that cooker temperature values obtained from the measurements and that estimated using the proposed approach were in good agreement. The mapping results indicate that the realized cooker is efficient in all the country throughout the summer season with temperatures exceeding 110 °C. The use of the cooker is reduced by going in South to North regions during the winter months, depending on the amount of solar radiations received. Nevertheless, the major area of the country is favorable for the use of the cooker during this period of the year even when the sky remains cloudy.

In this experimental study, the effects of reducing the compression ratio on the performance, emission, combustion, and startability of a 0.55 L single cylinder, direct injection diesel engine were studied in detail. Engine compression ratio (CR) was reduced from 16.5:1 to 15:1 and then to 14:1 by suitably modifying the geometry of the combustion chamber. Low compression ratios led to a reduction in both nitric oxide (NO) and smoke emissions with a marginal increase in fuel consumption. A special experimental setup with a motoring arrangement and a cold air and coolant conditioner unit was done, for investigating the cold starting ability of the engine. Also, a detailed analysis was made to characterize the transient behavior (cycle-to-cycle variations) of the engine with two compression ratios namely 14:1 and 16.5:1 during starting at different ambient conditions. The analysis showed that cold starting phenomenon of engine with a compression ratio of 14:1 got affected at reduced ambient temperature. The causes of misfiring during cold starting were investigated, and it is seen that the sequence of misfiring cycles was not entirely random.

In this study we were interested in the cementing of 9″ 5/8 casing corresponding to 12″ ¼ drilling section from an oil well drilled in the field of Hassi Messaoud in southern Algeria. This section is located in a very critical geological layer called LD2 (Horizon B), which is characterized by the production of calcic chloride waters that are very aggressive and virulent. Therefore the complexity of the geological formation encountered when drilling implies the need for a very precise pumping process to check pore pressure and the venus. This constraint has been imposed in high density work to avoid the dilution of cement slurry by chloride calcic waters. As a consequence, particular attention must be given to the proper control of the properties of cement slurry such as adequate rheology in order to achieve the target of obtaining a sustainable cement sheath. The cement type is of great importance in performance. Here we used a mixture of salt-saturated water with some basic additives and a combination of three materials: Dyckerhoof cement class G blended with the silica flour and hematite powder as a powerful additive to maintain the density of the slurry.

This work addresses the recovery of a liquid effluent by thermal evaporation. It is a digestate of pig manure, rich in N, P, and K (Granier 1993; Latimier 1996; Levasseur, Composition et volume de lisier produit par le porc: Données bibliographiques. TECHNI 21(4):16–19, 1998). The effluent was subjected to anaerobic digestion and phase separation by centrifugation. Several recovery scenarios for the liquid phase of a waste with 2.3% DM (Dry Matter) are analyzed.Because of the high consumption of fossil energy in the world, we analyze in this work the evaporation of this effluent using solar energy, in order to concentrate N, P, and K elements. The device consists of a stainless steel plate with a tilt angle of 30° and is not covered with glass. The liquid circulates as a film on the steel plate and is exposed to a 6000-W solar simulator.This work is divided into two primary parts. The first part is the thermophysical characterization of the effluent comparing to water. In the second part, evaporation tests with liquid effluent were performed. So, experimental tests will be valid by determining the equations of heat and mass balances on the plate and on the film (Bouchekima 2001; Chen 1986; Brau, Support de cours de convection pour 3 GCU. Insa de Lyon, département de Génie Civil et Urbanisme, 2006).Before starting the tests, the plate is exposed to solar radiation until stabilization of its temperature. A validation of the temperature of the plate, depending on solar flux and temperature of air, in laminar regime, was performed (Huetz-Aubert, Revue Phys Appl 17:251–260, 1981). We find that when the solar flux increases, the temperature of the plate increases. However, if solar flux is constant, the temperature of the plate decreases when the air temperature increases.The liquid circulates as a film flowing from the top of the plate. Local heat flux measurements, temperatures, and evaporated flow for input flow rate from 1 to 5 g/s are determined and compared with experimental results.

Carbon capture for fossil fuel power generation draws an increasing attention because of significant challenges of global climate change. This paper aims to explore the optimal operation of MEA-based post-combustion carbon capture (PCC) process for natural gas combined cycle (NGCC) power plant. Levelized cost of electricity (LCOE) is formulated as the objective function to be minimized in optimization. The rate-based steady state process model including the absorber, stripper and compression train and other auxiliary equipment was developed in Aspen Plus® to give accurate prediction of process performance. The techno-economic estimate was carried out for the base case for whole chain of NGCC integrated with PCC, CO₂ transport and storage (T&S). The optimal operations were investigated for the carbon capture level under different carbon price, fuel price and CO₂ T&S price. The study shows carbon price needs to be more than 100 EUR/ton CO₂ to justify the total cost of carbon capture from the NGCC power plant and needs to be around 150 EUR/ton CO₂ to drive carbon capture level to 90–95%. Higher NG price and CO₂ T&S price would cause a greater operating cost of running carbon capture process; thus a higher carbon price is needed to re-justify the cost of high carbon capture level of PCC process.

Current research focuses on the fabrication of the dye-sensitized solar cells (DSCs) based on titanium dioxide (TiO₂) compact layer deposited by the spray pyrolysis deposition (SPD) technique. TiO₂ compact layers have been grown on fluorine-doped tin oxide (FTO) glass substrates by the experimental aerosol-assisted SPD setup. This setup is designed and constructed for the research under the following conditions: substrate temperature of 300 °C, 400 °C, and 500 °C; initial solution concentration of Ti (IV) isopropoxide and ethanol of 0.5 ml and 100 ml, respectively; carrier gas pressure of 0.1 bar; nozzle-to-substrate distance of 20–30 cm; and spraying time of 5–10 s. The characterization instruments such as HITACHI (S-2700) scanning electron microscopy (SEM), BRUKER (D500) X-ray diffractometer (XRD), and JENWAY 7310 UV-Vis spectrophotometer have been used to investigate the film properties. Dye-sensitized solar cells (DSCs) were assembled based on a bare FTO glass, FTO coated with TiO₂ compact layer and with conventional TiCl₄-treated film. The current density (J_SC) and overall energy conversion efficiency of the device have been improved from 11.31 to 12.8 mA/cm2 and from 3.8% to 6.4%, respectively. However, the dye-sensitized solar cell based on TiCl₄-treated film presented the best results with efficiency of 7.35% and current density of 13.08 mA/cm2.

Biomass is the most common form of renewable energy and is, among the renewable forms of energy, the major source of the primary energy supply. It accounts for about 10% of the world’s energy consumption and can be converted to other usable forms of energy like biofuels. The aim of this work is to investigate the use of Citrullus colocynthis as a potential feedstock for biodiesel production by its seed oil transesterification. C. colocynthis seed oil was transesterified using sodium hydroxide as a basic catalyst at 60 °C and an oil/methanol ratio of 1:6 to produce its corresponding methyl esters. The physicochemical properties of the methyl ester produced (viscosity, refractive index, density, etc.) were measured and compared with the standards norms. The great potential of C. colocynthis oil is clearly presented in this study.

This study aims to develop a comprehensive decision-support system (DSS) for design and management of local bioenergy supply chains by tackling inherent uncertainties. To this aim, a fuzzy programming-based multiobjective-mixed integer linear programming (MILP) model is constructed. To explore the viability of the proposed DSS, computational experiments are performed on a real-world problem, and further analyses are conducted. The results reveal that the proposed model can effectively be used in practice.

The thermogravimetric analysis (TGA) was investigated to determine the kinetic parameters of high-density polyethylene (HDPE) with and without catalysts. In this work, we propose the use of “free” catalysts obtained from shells because they generally contain CaCO₃ as a main Ca-based component. The effects of the nature and the quantities of catalysts, with and without calcination in air at 800 °C for more than 4 h (Viriya-empikul et al. Bioresour Technol 101:3765–3767, 2010), on plastic pyrolysis were studied. Catalysts used are the commercial zeolite (as a reference catalyst): zeolite ZSM-5 (10%), ZSM-5 (20%), oysters’ shell (10%), oysters’ shell (20%), eggs’ shell (10%), and eggs’ shell (20%). The apparent activation energy and the pre-exponential factor were determined. Our results were compared to other works with and without different catalysts and under different operating conditions such as isothermal conditions, flow rates, and heat rates.

The coasts of the world are interconnected by extensive use of shipping routes. Ballast water is carried in ships to provide stability and trim. Discharge of ballast water may impact on the marine environment in various ways, and it is the major vector for the transfer of nonindigenous aquatic species from one region to another. These organisms often include non-native, alien, nuisance, exotic, and invasive species which can cause extensive ecological and economic damage to marine ecosystems. Introduction of invasive species is one of the major factors adversely affecting biological diversity, and they threaten many native species in the host environment till the extinction. To prevent and minimize the risk of introduction of invasive species, ballast water treatment technologies and legislations were developed by the International Maritime Organization (IMO).Coasts of Turkey are one of the most vulnerable areas for the intensive maritime traffic. Currently, there is 23 million tons of ballast water discharged to national coastal waters. Turkey ratified Ballast Water Management Convention (BWMC) in October 2014, and BWMC will enter into force 12 months after it has been ratified by 30 states representing 35% of the world’s merchant shipping tonnage.

Energy consumption is inevitable for human existence. There are various reasons for the search of an alternative fuel that is technically feasible, environmentally acceptable, economically competitive, and readily available. Several alternatives such as wind, solar, hydro, nuclear, biofuel, and biodiesel have been suggested, but all of them are still in the research and development stage. The inventor of biodiesel engines, Rudolf Christian Karl Diesel (1858–1913), demonstrated the use of vegetable oils as a substitute for diesel fuel in the nineteenth century. He believed the utilization of biomass fuel will become a reality as future versions of his engine are designed and developed. Biodiesel is a monoalkyl ester of fatty acids produced from vegetable oils or animal fats (Appl Energy 104:683–710, 2013).The increasing production of waste frying oils from household and industrial sources is a growing problem around the world. This residue is regularly poured down the drain, resulting in problems for wastewater treatment plants and energy loss, or is integrated into the food chain through animal feed, thus becoming a potential cause for human health problems (Renew Sust Energy Rev 10:248–268, 2006).In order to recover these wastes and reduce production costs of biodiesel (up to 60–90%), the used cooking oil remains the key element, but its treatment is more complex than fresh vegetable oils. Most used frying oils contain a large amount of free fatty acids, so an esterification step is necessary before transesterification. This reaction is usually carried out in batch reactors with pressure and temperature conditions where the esterification reaction acts as the limiting step of the production.The aim of this work is to eliminate the fatty acids before starting transesterification and testing the effectiveness of ethanol and methanol to ensure a better yield in the production of biodiesel from used frying oil.

The ongoing development driven by the progression of technology and science is leading to enhanced energy consumption. Most of the in-use energies are from restricted fossil fuel and most of the fossil fuel consumers are spark-ignition engines. On the other hand, the main duty of the development engineer is to decrease cost and increase power output and trustworthiness of an engine. In trying to succeed in these goals, they have to try out different design concepts. Hence, the objective of this study is to investigate the effect of oxygen additive in intake of fuel consumption, brake torque, and brake power as a new way to increase the performance of the spark-ignition engine. In order to effectively increase brake torque and brake power, the percentage of oxygen content in air was changed. The engine’s performance characteristics under various engine speeds and oxygen concentrations were measured. The experimental results showed that the brake torque output, brake power output, and fuel consumption were increased significantly by increasing the oxygen concentration at the intake. Finally, it is found that oxygenating the air causes to increase the performance on spark-ignition gasoline engine.

Recycling of waste automobile tyres is of great interest today, because recycling offers potential products for further use in different applications. Tyre pyrolysis oil (TPO) is one of the principal products obtained when waste automobile tyres are subjected to pyrolysis process. This paper describes some possible methods of using TPO as an alternative fuel in a direct injection (DI) diesel engine. The results indicated that TPO-based fuel blended with diesel fuel (DF) improvement by desulphurisation and distillation gave better results in terms of combustion, performance and emission parameters than those of diesel fuel operation. But, TPO can be used only up to 90% in the form of blend with DF, even after improving its fuel quality. The TPO can be used solely as a fuel in the diesel engine by running the engine on a dual fuel mode. The combustion, performance and emission parameters of the engine run on TPO-based fuels on different methods are analysed, compared with those of diesel fuel operation in the same engine and presented in this paper.

Considering the important role of verification and validation processes in design and analyses of combustion systems, and the growing role of natural gas as a clean alternative fuel along with the deviation in its composition among different sources, this study aims to investigate the effect of natural gas composition on the correctness of a model’s calibrated results. To accomplish this, a comprehensive one-dimensional gas dynamics model of a single-cylinder test gas engine working with pure methane as fuel is calibrated versus air mass flow rate, added fuel mass flow rate and in-cylinder pressure profile. The model is then employed to predict the performance of the same engine working with two compressed natural gases distributed in Mashhad and Tehran, which the latter is considered to have the largest deviation from the pure methane in composition. The results are compared with experimental findings, and the results indicate that the model comes to acceptable verified results (with error root mean square of less than 3%).

Process development unit (PDU) for amine-based post-combustion carbon capture located at Clean Coal Technologies Centre in Zabrze, Poland, was used to validate split steam configuration. Process development unit having a capacity of up to 100 m3_n/h was designed to test the amine scrubbing carbon capture process from flue gases or mixtures of technical gases. Flexible process flow sheet of the unit allowed investigation of the split-flow process.The split-flow flow sheet modification was compared to a standard system for chemical absorption based CO₂ capture. The tests were conducted using well-accepted baseline solvent: 30%wt aqueous MEA solution. The flow sheet modification resulted in a decrease of reboiler heat duty by 4–6% and an increase in CO₂ recovery. Split-flow process modification was examined together with standard process flow sheet, and a vast number of process parameters recorded during the trials have been presented. The explanation of beneficial effects of split-flow designs has been shown together with detailed analysis of experimental trials carried out using PDU for amine-based post-combustion carbon capture. This paper is also a valuable source of experimental data useful during validation of models.

Hydrogen is considered as the most promising energy carrier for providing a clean, reliable, and sustainable energy system. It can be produced from a diverse array of potential feedstocks including water, fossil fuels, and organic matter.Electrolysis is the best option for producing hydrogen very quickly and conveniently (Sasikumar et al., Int J Hydrog Energy 33:5905–5910, 2008).Water electrolysis as a source of hydrogen production has recently gained much attention since it can produce high-purity hydrogen and can be compatible with renewable energies. Besides the water electrolysis, aqueous methanol electrolysis has been reported in several studies. The aqueous methanol electrolysis proceeds at much lower voltage than that with the water electrolysis. As a result of the substantially lower operating voltage, the energy efficiency for methanol electrolysis can be higher than that for water electrolysis (Pham et al., Int J Hydrog Energy 38(1):73–81, 2013).In this paper, we are interested with methanol electrolysis in order to produce hydrogen.

This article deals with an experimental investigation of polypropylene (PP) by pyrolysis process to produce fuel. For the experimental conditions chosen, condensation begins after 43 min of heating, at a temperature of 385.8 °C. The liquid initially has a yellowish color, and then becomes reddish. Under the operational parameters, the liquid, solid, and gas product mass yields are respectively 63.13%, 0.36%, and 36.51%. The time-evolution of PP pyrolysis temperature difference between the bottom and the middle of the reactor, the time-evolution of gas volumetric percentage, and the liquid chromatogram are illustrated and discussed. A list of the major components of the PP pyrolysis liquid is enumerated. The obtained PP liquid characteristics are compared to other fuels, such as gasoline, kerosene, and diesel.

Hydrogen is a suitable alternate fuel as it can be produced from renewable sources, and also it does not emit carbon monoxide, hydrocarbons, particulates, and carbon dioxide (CO₂). The homogeneous charge compression ignition (HCCI) mode is a relatively new engine combustion concept wherein a lean premixed air-fuel mixture is admitted and ignition occurs at multiple points throughout the combustion chamber by compression. The main merits of HCCI are extremely low levels of nitric oxide (NO) and smoke emissions with the potential to develop high thermal efficiency. In this work, experiments were performed on a stationary engine in three different modes of operation, namely, hydrogen-fueled HCCI (HHCCI), hydrogen diesel HCCI (HDHCCI), and neat diesel compression ignition (CI). In the HHCCI mode, thermal efficiency was better than the conventional diesel mode, and emission of NO was very low. The charge temperature had to be held at the lowest level to avoid misfire as this resulted in the best combustion phasing and thermal efficiency. When very early in-cylinder injection of diesel was also employed along with hydrogen diesel HCCI, i.e., HDHCCI mode, intake charge heating was not needed as diesel aided the ignition process. Operation in the neat diesel HCCI mode led to advanced combustion and low thermal efficiency. However, the additional use of hydrogen led to high thermal efficiencies because of proper combustion phasing (combustion occurring close to top dead center). The operating range in the HDHCCI mode was 2–4 bar of brake mean effective pressure (BMEP). Induction of hydrogen also lowered the concentration of NO, smoke, carbon monoxide (CO), and hydrocarbon (HC) emissions as compared to the diesel-based HCCI mode. On the whole, the HHCCI mode is promising in terms of thermal efficiency and low emissions. The HDHCCI operation with common rail injection enables proper combustion phasing and has potential for high thermal efficiency with low emissions. The results indicate that the engine can be operated in the CI mode at low outputs and switch over to HCCI operation with neat hydrogen along with charge heating in the low BMEP range (0.5–2.2 bar). Beyond this output, operation can be in the hydrogen diesel HCCI mode which is viable without heating the intake charge till a BMEP of 4 bar. At higher BMEPs, the engine can only be operated in the neat diesel CI mode.

In this chapter, we investigate the thermal behavior of phase change materials (PCM) for heating indoor applications. The model consists of PCM/concrete wall, located in Casablanca – Morocco (33°36′N, 07°36′W). It was observed that a high amount of heat is stored in the wall because the PCM offers an important heat density, and latent heat stored during the melting of PCM can be used for the night heating. It emerged that the PCM/concrete wall is able to provide better living thermal conditions with less inner temperature fluctuations.

This study investigates optimum insulation thickness of a building wall in the city of Bilecik, Turkey. The optimum insulation thicknesses are determined using life cycle cost analyses and a novel method based on the environmental impact analysis. Two different insulation materials, rockwool and polystyrene, are considered in the analyses. In this regard, the fuel consumption, the CO₂ emission, and the environmental impacts of the system related to energy loss are determined first. Next, within the life cycle cost (LCC) analysis, insulation cost, fuel cost, and the total cost are calculated. The results for the environmental impact of the system, the net environmental saving, the fuel consumption, the CO₂ emission, and the total cost according to the insulation thickness are then given. The optimum insulation thicknesses calculated by environmental impact analysis and LCC analysis are compared. Finally, the main concluding remarks are listed while the recommendations are made.

To achieve sustainable development, there needs to be a focus on decreasing use of non-renewable energy sources and greenhouse gas emissions. In this regard, many studies focus on the strong relationship between energy and the environment. This study aimed to introduce the exergy analysis method into the urban planning field to find out the amount of exergy, rather than energy, that can be conserved in a building block when a solar envelope-based design is applied. In addition to the known energy-efficient design parameters, a criterion for the solar envelop method is integrated into a single method. This hybrid method includes taking into account the requirements for orientation, spacing, landscaping, and building form, as well as the building height properties as proposed in the solar envelop method. The solar envelop method depends on understanding the changing position of the sun throughout the day and year. If this dynamic behavior can be a factor in the design of an urban area, environmental friendliness, sustainability, and reduced energy consumption can comprehensively be achieved in cities.

Limiting heat losses during ventilation of indoor building spaces has become a basic aim for architects. Much experience has been gained in terms of ventilation of indoor spaces. Nevertheless, due to the complex applications, attempts to create a theoretical base for solving the problems related to the issue are limited, especially determining the minimum ventilation period required within a designated space. In this paper, we have approached this matter, both theoretically and computationally. The conclusion we reached was that controlled ventilation of spaces through vent holes that successively open and close at regular time intervals can limit the excessive circulation of air masses, which in turn limits heat losses.Air change rates through open and tilted windows in rooms of residential buildings driven by atmospheric motions are investigated to evaluate natural ventilation concepts. Model of thermal building simulations is used. A separated sample storey and a sample single room in larger scales were used to measure air transport through window openings under the influence of the external pressure distribution.

In this paper, the author has developed a processing of digitized infrared (IR) images using mathematical IR image filtering. This method was validated first, in the case of surfaces with known and controlled temperature and emissivity. In the process of thermal technologies, it is very important to know the temperature field during industrial manufacturing. In this case mainly the contactless methods are very useful. To eliminate the effect of the emissivity on the surface under scrutinies the surface is coated with some special coating.Computer processing of the infrared (IR) images considerably speeds up the evolution of the measurements results. Processing of digitized IR images may be carried out by a variety of approaches and methods. On the whole, it may be said that it is expedient to tailor the strategy and the method of evaluation to the phenomenon under scrutiny. This, in some cases, calls for both heat engineering experiences and technical intuition. Image filtering is a special and an uncommon method of IR image analysis. The present author has no information about publications on the mathematical filtering of IR images. The first paper on that topic by the present author was published in 1997. The mathematical IR image filtering in general is suitable for detecting some thermal faults which are difficult to identify otherwise. Image filtering is based on the adequate transformation of the temperature field, i.e. the modification of the temperature values in the pixels of the image.Some other papers (Benkő I. Applications of infrared thermogrammetry in thermal engineering. In: Proceeding of the conference on quantitative infrared thermography (QIRT 92), Eurotherm Séries 27, Edition Européennes Thermique et Industrie, Paris, pp 343–349, 1992; Benkö I. Infra-red picture analysis in thermal engineering. In: Benkő I (ed) Proceedings of the tenth international conference on thermal engineering and thermogrammetry, MATE TE and TGM, Budapest, pp 46–52, 1997) report about infrared thermogrammetric (TGM) measurements made using a comparative technique for obtaining data on total and band emissivities of chosen specimens of different materials (metal, asphalt shingles, sealed and unglazed tile, felt, etc.) covered by selective different coating. The infrared radiation emitted by the surfaces was measured by AGEMA thermal imaging equipment with a special method (see Fig. 4).

The need for more speed for hypersonic aviation, reentry, and rocket propulsion vehicles increases as the quest for space and planetary exploration increases; improved materials are needed to withstand the conditions encountered by wing leading edges and propulsion system components in hypersonic aerospace vehicles as well as the extreme conditions associated with atmospheric reentry and rocket propulsion. Reports on arc-jet testing as the best ground-based simulation of thermal analysis on vehicle structure materials under reentry conditions are available but limited. Such tests provide mechanical, thermal, and chemical behavior of materials. In the present paper, a report on analysis through transient numerical simulation using COMSOL Multiphysics for heat transfer by conduction, convection, and radiation in porous ceramic and ceramic composite TPS tiles under reentry conditions is presented. Temperature profile for pure silica TPS tile is obtained in the first phase of the thermal analysis with surface conditions of pressure and surface heat flux equivalent to the reentry conditions. 1-D, 2-D, and 3-D analyses has been conducted in the next phase and studied the response of ceramic composite tile model from the family of ultrahigh-temperature ceramics at higher heat loads as experienced by leading edges.

Information and communication technology-led growth in remote sensing and image processing has unexplored potential of applications in the management of water resources and environmental systems for assessing hydropower potential and monitoring their hydropower production and performance. This project aims to advance the application of remote sensing in the context of managing water resource by integrating high-resolution remote sensing technology into a knowledge management system for the management of water resources and the infrastructure to control and harvest its power generating potential.Beyond its vast amount of oil, gas, and coal, the Republic of Kazakhstan has a hydraulic potential of about 170 billion kWh per year, with the technological potential being 62 billion kWh per year. Despite this enormous potential, only 27 billion kWh is being generated with hydroelectric power systems. The economic potential of small hydropower generating units alone is estimated at 7.5–11.0 terawatt-hours per year, of which only 5% is produced (United Nations Development Programme (UNDP) Kazakhstan, Water Resources of Kazakhstan in the new millennium, Report # UNDPKAZ 07, Almaty, 2004). However, their sustainable use demands a thorough restructuring of the existing system of natural water resource allocation and use as suggested by Zàuìrbek (National programme for water resources management in the Republic of Kazakhstan. KazNatAGRU, Almaty, 2013) which is largely in line with the literature on Integrated Water Resource Management (IWRM) (Biswas, Water Int 29(2):248–256, 2004; Jewitt, Phys Chem Earth 27(11–22):887–895, 2002; Thomas and Durham, Desalination 156(1–3):21–28, 2003).Our knowledge management system has the aim to support the user to develop credible and defensible water resource management plans in line with IWRM objectives and in particular:(a)Describe water resources and identify actual and emerging problems of water pollution and water use inefficiencies as well as infrastructure needs.(b)Formulate plans and set priorities for water quality, water use management, and infrastructure needs.(c)Develop and implement water quality management programs, water allocation strategies, and river basin asset management plans.Such applications (Argote et al., Manag Sci 49(4):571–582, 2003; Boddy et al., Autom Constr 16(5):596–606, 2007; Dalcanale et al., Environ Manag 47(3):443–455, 2011; Liao, Expert Syst Appl 25(2):155–164, 2003; Sandwahalia et al. 2008; Toman, Water Resour Manag IV 103:667–676, 2007) with the integration of a Geo-Information Systems (Chen et al., J Hydro Environ Res 4(3):253–264, 2010) have significant potential as a platform for managing environmental, water resource, and infrastructure data. This mapping and geo-spatial analysis of information will see further advancements by integrating models and near real-time remote monitoring systems (Burman, Image Signal Process Remote Sens V 3871:348–357, 1999; Chen et al. 2008; Legleiter et al. Earth Surf Process Landf 34:1039–1059, 2009; Lyzenga, Shallow-water reflectance modeling with applications to remote sensing of ocean floor. Proceeding of 13th international Symposium on remote sensing of environment, pp 583–602, 1979) thus providing a wide range of data modalities to enable high-speed visualization and analytics. To be tested as a prototype, this project will result in a comprehensive technical and economic feasibility study for investing in hydropower generation by quantifying flow volumes, identifying potential sites for water storage, and assessing geographic elevation gradients that are suitable to produce electricity with small hydropower stations.

A composite phase change material (CPCM) of myristic acid/palmitic acid/sodium myristate (MA/PA/SM) has been proposed by impregnating a porous material of purified damar gum, also called Shorea javanica (SJ), to improve the thermal conductivity of CPCM. The thermal properties, thermal conductivity and thermal stability, of CPCM were measured using differential scanning calorimetry (DSC) thermal analysis, hot-disc thermal conductivity analyzer, and simultaneous thermal analyzer (STA). Moreover, a chemical reaction between fatty acid binary mixture and SJ in CPCM was evaluated by Fourier transform infra-red (FT-IR) spectrophotometer. The results of this study showed that the thermal conductivity of MA/PA/SM/SJ composite phase change material (CPCM) was improved by addition of 3 wt.% of Shorea javanica into MA/PA/SM eutectic mixture without showing a significant change in the thermophysical properties of CPCM. Moreover, the eutectic CPCM also does not show occurrence of chemical reaction between MA/PA/SM and SJ, and it has a good thermal performance and thermal stability. Therefore, the MA/PA/SM/SJ CPCM proposed in this study can be recommended as a new novelty material for thermal energy storage application.

The solar energy as one of the most important energy sources is investigated for effective use in a variety of areas. Especially, with the tendency of depletion of fossil fuel consumption as well as their greenhouse gas emissions leading to atmospheric pollution and, hence, global warming and climate change, the value of renewable energy sources and solar energy is increasing rapidly. In the solar energy prediction, the relationship between solar irradiation and sunshine duration plays the most dominant role. The aim of this study is to apply harmonic analysis, coupled with the classical Angström-Prescott equation, to solar irradiation and sunshine duration data for the extraction of its relevant relationship. Firstly, it helps to eliminate the periodicity from the measurement record and then the application of the Angström-Prescott model is applied, which is then tested and compared with the classical Angström-Prescott model based on the regression approach. The applications are achieved by use of measurements at the major city in the south-eastern Anatolian part of Turkey, namely, Diyarbakır. The improved model provides more successful and reliable outputs than the classical approach.

The present study makes use of the energy and entropy measurements of the human brain for detection of brain-related abnormalities. The electroencephalogram (EEG) records the brain’s signals, which contain valuable information about the normal or abnormal state of the brain. Many studies have focused on the nonlinear analysis of EEG mainly for the characterization of abnormal (epileptic) brain states. Here the EEG is first decomposed into four levels using wavelet packet transform. The packets on each level of the decomposition are a linear combination of wavelet basis functions. All the frequency bands, i.e., delta, theta, alpha, beta, and gamma, are determined. Then for the feature extraction vector, the statistical parameters like entropy, energy, mean energy, and mean Teager energy are used. The effects of the frequency rhythm of brain waves are analysed. The abnormal EEG is more affected on the delta and theta frequency bands. The classification is done using the adaptive neuro-fuzzy inference system (ANFIS). It has been observed that mean Teager energy has a minimum training error compared to other parameters.

In this paper, we present an optical simulation of concentrating solar tower system using different forms of cavity receiver. Mathematical model used to find the position of the sun, angle of incidence, position of the reflected ray and orientation of heliostats is developed in MATLAB. For each heliostat, the angle of incidence is included in the calculation of the reflected radiation. Optical simulation was performed employing TracePro ray tracing software using Monte Carlo ray tracing method to get the concentrated solar ray distribution in the cavity receiver. The aim of the work is to seek the geometry that gives the best distribution of concentrated rays, with the best efficiency.

Accurate and reliable wind prediction is vital for sustainable wind power system. Especially in the atmospheric boundary layer, the difficulties of short-term wind forecasts affect the reliability of the model results. The forecast ability of the numerical weather models may be improved through artificial neural network (ANN), principle component analysis (PCA), genetic algorithm (GA), and other similar methods. In this study, the evaluation forecasts were made with the Weather Research and Forecasting/Advanced Research (WRF/ARW) model run with six different planetary boundary layer (PBL) parameterizations. The site of test station is located in the northern part of Istanbul with coordinates 41° 30′ N and 28° 66′ E at 51 m over sea level; it was found by Wind Atlas Analysis and Application Program (WASP) (Fig. 1 and Table 1). The performance of WRF/ARW for wind forecasting is assessed with measured wind variables at different hub heights at test station. The observed wind profiles are compared with WRF/ARW forecast, which uses the BL schemes based on turbulence kinetic energy. All the simulated schemes tend to underestimate or overestimate the wind at hub height during day and night. The diurnal evolution and the expected transitions of wind speed, temperature, and the alpha-parameter are evaluated by all the schemes.In the proposed study, the weather research and forecasting model (WRF) is first run with six different physical conditions to find the appropriate variables of actual atmospheric condition during the experiment time period. Next, the study explored artificial neural network (ANN) methods to forecast the wind speed in Terkos (Durusu), Istanbul. To reduce the noises of the numerical weather prediction model, ANN is applied to forecast the short-term wind speed and is approved at the designed wind turbine farm of Terkos. Finally, the performance of the proposed approach is evaluated using observed data. The forecasting performance was improved by the ANN method.

Solar power has significant potential to reduce reliance on conventional energy sources in South Africa. A prefeasibility study for a communal solar water heating system (SWHS) is performed for an apartment building in the Cape Town area. Energetic-economic modeling of the system is performed by calculating the solar fraction and fundamental indicators of the financial analysis, such as internal rate of return (IRR), net present value (NPV), and benefit–cost ratio. Results indicate that a SWHS with a solar fraction of 32% and a benefit–cost ratio of 3.05 is realizable. Additionally, sensitivity analysis of financial results with respect to incentive rebate amount and electricity escalation rate is performed.

This paper aims to evaluate the environmental footprint of an exterior wall assembly made of straw bundles and to compare it with the one of a conventional wall. The used methodology is Life Cycle Assessment. The EIMME® software, associated with the eco-invent database, is used to quantify the potential environmental impacts of the considered walls. Obviously, some steps of the wall life cycle have a small environmental footprint, for example, the consumer use step provides low impacts, while the end of life step (post-consumer) allows a “saving” (i.e., a diminution) of impacts because a part of the materials can be reused. On the other side, the raw material procurement and manufacturing steps are at the origin of the greatest impacts. Among the chosen indicators, the main environmental impacts are found to be the energy consumption, the air toxicity, the 100-year global warning, and the use and treatment of water. To minimize the impacts (environmental footprint), local producers should be preferred. The assembly is finally compared to a conventional wall realized by using glass wool and breeze blocks. According to the obtained results, the “straw wall” is shown to be better for the environment regardless of the considered indicator, excepted for the air toxicity for which the values of the two studied walls are of the same order of magnitude. It is shown that the only alternative to the conventional insulation for the environmental point of view seems to be the use of “straw walls.”

In this chapter, an experimental setup of an integrated air conditioning split heat pump system is elaborated in detail together with a performance analysis. The proposed energy system consists of a standard split air conditioning device and boiler for hot water preparation, and the whole system is driven by a small photovoltaic (PV) plant. The energy system was tested in a cooling and heating regime in a location with typical Mediterranean climate to determine the average performance parameters. The main goal of the conducted research was to utilize existing market-available energy technologies that can be found in majority of building applications, both residential and commercial, in the form of a modified (hybrid) energy system. The performance analysis shows a market potential for the proposed energy solution as it is suitable from the aspect of energy efficiency and also presents a renewable energy system that can be easily implemented into building applications. Namely, the average COP value was 5.3 for heating mode and 5.4 for cooling mode, the mean electricity consumption ranged from 0.55 to 1.14 kWh, the mean water temperature ranged from 42 to 46 °C, and, finally, the PV system autonomy ranged from 6 h in winter operation to 12 h in summer operation. In general, the cooling mode was more efficient in terms of achieved performance parameters.

The technical and economic feasibility of the installation of a mini-hydroelectric power plant on El Valle River in Venezuela is assessed. Special attention is paid to modeling Venezuela’s energy and economic scenarios. Sensitivity, risk, and emission analyses are also carried out. The results of the study show very attractive economic indicators, such as a 280.3% internal rate of return and a 0.4 years payback period. The positive results of the study are an indication that clean energy could find very fertile scenarios in countries such as Venezuela, where the advantages of their application may not be evident.

After driving power, the air-conditioning system is the main item of power load for electric vehicles. The air-conditioning load is not only affected by the external environment, but also by the driving modes. Moreover, the cooling load calculation is very different to that for buildings. This study develops an Excel-VBA-based air conditioning load calculation tool. Air-conditioning load calculation is based on inputs of ambient air temperature, wind speed, solar radiation, driving mode, and other parameters. The calculation also considers the vehicle’s shell structure and materials, glass radiation angle, low-e glass, occupancy, outdoor air, etc. Heat conduction, convection, and radiation are all considered in the calculation of the surface temperature of the vehicle’s shell structure. The calculated results agree well with the measured data and thus verify the developed calculation tool. In addition, the dynamic cooling load can be calculated when incorporating driving speed, GPS location, etc. An energy control strategy for different driving modes can be applied for dynamic cooling load. A variable speed compressor was studied for regulating the energy need of electric automotive air conditioning. It was found that occupant comfort can still be satisfied while reducing air-conditioning energy consumption, and hence prolong the driving range and battery life. It was found that when a five-passenger car has only a driver in the car, the control strategy can reduce the air-conditioning load by 11.2%. With further optimization of the compressor operation matching the cooling capacity, the compressor power consumption can save up to 52.8%.

The energy needs for seawater desalinization by reverse osmosis are such that they constitute the largest share of operating costs. Seventy percent of this energy is absorbed by the only device used to bring pressure membranes, and hence its importance in the price structure of the cubic meter desalinated water. Thus, research in the field of energy recovery from the concentrate was an important factor in lowering desalination cost.The pressure exchanger (PX) is a device used for transferring pressure energy from a relatively high-pressure fluid flow to a relatively low-pressure fluid flow.The PX transfers the high-pressure concentrate (reject) of reverse osmosis system to seawater from the filter cartridges, reducing by nearly 50–60% the pump size and pumping cost, with the efficiency exceeding sometimes 97%.The application of the pressure exchanger technique in BOUSMAIL desalinization station located 30 km west of Algiers gives an energy gain of 18% compared to the Pelton turbine, which is being used now. It recovers energy directly by reducing the size of the high-pressure pump of 231.5–108 m3/h and works as a pump independent of the main pump, which gives a stable system.It is also noted that the compact size and reduced PX modules allow its location in smaller premises, minimizing the visual impact with its optimum integration on its environment.

The distillation sequences of selected two-case hydrocarbon mixtures are determined in this study by an exergoeconomic multi-objective optimization using a genetic-based solver. A sole computer program (DISMO) is developed for achieving this aim including the database of thermophysical properties and genetic algorithm-based solver. The number of possible sharp distillation sequences increase markedly with the number of feed components and proper sequencing from maximum exergetic profit and minimum exergy destruction. Also, a parametric investigation is made for various weighing factors of objective functions for the sake of revealing the true characteristics of the system. The results of the illustrated cases show that the algorithm is applicable for the determination of the optimum alternative of the distillation sequences as the Pareto Solution Set and the optimum configuration is considered, and it is found that the maximum profit and minimum exergy destruction is 107,647 $/kW and 9302 kW, respectively, with a sequencing of 5-4-3-2-1 and 2-1-4-5-3 for a 6-component hydrocarbon mixture.

This chapter deals with modeling, optimization, and simulation of photovoltaic generator (PVG) connected to domestic three-phase electrical network. The connection is made through a current-controlled voltage source inverter which not only converts photovoltaic (PV) energy from DC power to AC but also injects the maximum power into a three-phase electrical network with unit power factor. A decoupling system which can protect the generator from perturbations that can get to the electrical network supply is introduced.To avoid battery storage problems, the total energy produced by the PVG has to be injected into the network, whereas the electricity requirement for domestic use has to be withdrawn from the network supply.

In the family of renewable technologies, photovoltaic (PV) systems today attract considerable attention (Dornfeldt, M.: The future of the Kazakh energy sector and the Kazakhstan 2050 strategy. Retrieved November 2, 2014, from 18th REFORM Group Meeting http://www.polsoz.fu-berlin.de/polwiss/forschung/systeme/ffu/veranstaltungen/termine/downloads/13_salzburg/Dornfeldt-Salzburg-2013.pdf (2014)). However, on-grid, PV market is not a profitable sector by itself. It is dependent on the governmental support, which still must stimulate investment with subsidies. Thus, this paper presents the technical and economic prefeasibility analysis of implementing a residential photovoltaic system in South Kazakhstan, using the clean energy project analysis tool RETScreen® V.4. The different systems available for PV cells are considered; however, with the climatic conditions in South Kazakhstan, the study focuses on polycrystalline solar cells (Poly-Si) due to its optimal specifications for the region. Furthermore, local company Astana Solar has implemented a production line of Poly-Si photovoltaic modules using Kazakhstani silicon (Astana Solar: About company. Retrieved November 2, 2014, from: http://www.astanasolar.kz/en/about-us (2012)), which could make the project even more attractive to the country.In the analysis presented, solar resource in South Kazakhstan was estimated using solar radiation data from NASA Surface Meteorology and Solar Energy. For a 6.6 kWp system, installed in the roof of a home, it is found that 8834 MWh of electric energy is exported to the grid on an average per year. The suitability of city-level feed-in tariffs (FITs) to promote solar photovoltaic panels in Kazakhstan is included in the analysis, despite that it is very recent and had not been thoroughly examined yet (Ministry of Energy of Kazakhstan 2014). Several different economic and financial indicators were calculated, such as the Internal Rate of Return (IRR), Net Present Value (NPV), Benefit-Cost (B-C) ratio, Cost of Energy Production (CEP) and Simple Payback (SP). All indicators for all sites explored in South Kazakhstan showed favorable conditions for deployment of the proposed residential solar PV system. The highest IRR of 17.9%, NPV of $14,523 and B-C ratio of 9.65 was observed in Shymkent and the lowest IRR of 16%, NPV of $11,366 and B-C ratio of 7.84 was observed in Taraz. Meanwhile, it can be observed that Shymkent got the shortest SP period of 9.9 years while Taraz got the longest payback period of 10.8 years.The technical and economic analysis shows also that the implementation of an additional 50% subsidy on total initial cost recently approved affected very positively the PV-based generation system in southern regions. Therefore, it is found that all southern Kazakhstan is a fertile territory to implement on-grid residential projects.

The kind of energy that buildings need changes, like heating energy, cooling energy, electrical energy, and thermal energy for hot top water. Usually, the processes or systems that produce thermal energy emit pollutants while they produce heat because of the fossil fuels they use. A lower consumption of thermal energy will contribute not only to a reduction in the running costs but also in the reduction of pollutant emissions that contribute to the greenhouse effect and a lesser dependence of the hospital on the external power supply. Cogeneration or CHP (combined heat and power) is the system that produces power and usable heat simultaneously. Combined production of mechanical or electrical and thermal energy using a simple energy source, such as oil, coal, natural or liquefied gas, biomass, or the sun, affords remarkable energy savings and frequently makes it possible to operate with greater efficiency when compared to a system producing heat and power separately. Because of the life standard of humanity in new age, energy sources must be continually improved and updated. For this reason, the installation of a system for the simultaneous generation of electrical, heating, and cooling energy would be one of the best solutions if we want to have qualified energy and reduce investment and operating costs and meet ecological requirements. This study aims to bring out the contributions of cogeneration systems to the environment and sustainability by saving the energy and reducing the emissions.

Solar energy is thought as the main source of all energy sources in the world, and it can be used in many applications like agricultural areas, heating-cooling or electricity production directly or indirectly. Greenhousing is the first one of the agricultural activities that solar energy can be used directly in. Greenhouses offer us suitable conditions which can be controlled easily for the growth of the plant, and they are made by using a covering material that allows the sunlight to enter into the system. Covering material can be glass, fibre glass, plastic or another transparent element. This study investigates the solar energy usability rates and solar energy benefitting rates of a semi-spherical (modified arch)-type greenhouse system according to different orientations and positions which exist under climatic conditions of Bayburt. In the concept of this study, it is tried to determine the best direction and best sizes of a semi-spherical greenhouse to get the best solar benefit from the sun. To achieve this aim, a modelling study is made by using MATLAB. However, this modelling study is run for some determined shapes and greenhouses, and it can be used for different shaped greenhouses or buildings. The basic parameters are determined as greenhouse azimuth angle, the rate of size of long edge to short and seasonal solar energy gaining of greenhouse.

Solar radiation is an important parameter in hydrological models. In Algeria, the global solar radiation and its components are not available for all locations due to which there is a requirement of using different models for the estimation of global solar radiation that use climatological parameters of the locations.In this study, we developed a model to estimate solar radiation in arid area. Empirical constants for the model have been estimated, and the results obtained have been tested statistically. The results show encouraging agreement between estimated and measured values.

The industry sector is facing many challenges such as global competition, energy pricing, environmental impact among others. Consequently, the necessity of energy efficiency measures has become evident, framing the objective of this project as to assess the technical and economic prefeasibility of implementing energy efficiency measures in a dairy products manufacturing company located in the south of Reunion Island with the help of RETSCreen®, a Clean Energy Project Analysis Software. The scope of the project is focused in one of the nine buildings where the company accomplishes different production processes, specifically in the ultra-high temperature pasteurization facility building (UHT).

One of major practical and unavoidable problems in the field of photovoltaic farm installations is partial shading, a complicated situation in which the conventional popular maximum power point tracking (MPPT) methods are ineffective. The main contribution of this paper is a simulator-based an algorithm that is able to track the global maximum GP under solar irradiance mismatching conditions or partially shaded conditions (PSCs), in the event of the presence of multiple local maxima, where the photovoltaic characteristics get more complex with more than one peak. To prove the reliability of the proposed system two procedures are carried out, first with different cases with varying degrees of partial shading, and secondly to compare the results with the results in the literature. The algorithm proposed is simple, practical, and can be computed very rapidly. Matlab/Simulink is employed for the simulation studies.

This paper focuses on the impact of LED luminaire in terms of illuminance and energy consumption for roadway lighting system. The comparison between HPS and LED luminaires in terms of illuminance and uniformity with the standards of Department of Highways of Thailand is presented with DIALux program. In addition, the arrangement of roadway lighting pole in case of without and with isle including the different polar distribution curves of LED luminaire is also considered and compared. The objective of this paper is to study and propose the improvement of installation with LED luminaire for roadway lighting system in terms of illuminance and uniformity using the mounting height adjustment method and the pole spacing adjustment. The results show that, by focusing on average illuminance and uniformity, the type of polar distribution curve and the adjustment of pole spacing of lighting pole can significantly improve the installation of LED luminaire for roadway lighting and it will be useful in the installation of LED luminaire for roadway lighting in the future.

In this past few years, installation of distributed generator (DG) has become topic of interest in many countries due to rapid increase in energy and environmental issue. Generating power from renewable source has been proposed to compensate fossil fuel that is currently depleted. Wind power is one of the renewable energy sources that gains a huge attention, and many utilities are connecting wind power to distribution system. This number is going to get higher in the near future. Research on influence of wind power on system must be done in order to ensure the reliability of power system. This paper aims to study an impact of wind power-integrated distribution system when fault occurs in the system for various conditions. Many factors capable of changing system characteristics have been taken into account such as distribution system consisting of multi-wind power generation, size of wind power generation, fault type, and location of fault. Distribution system under this study is modeled based on 22 kv distribution network of Provincial Electricity Authority (PEA) in Thailand. Simulation will be done by using PSCAD/EMTP. Result obtained from case studies will be used to analyze and evaluate the effect of installation of wind power. The result indicates that the DG contributes significant fault current to the system when fault occurs.

The effects of the variations of process stream properties on the energy targeting of a heat exchanger network were investigated. The thermodynamic properties of a process stream mixture, including the specific heat capacity, viscosity, thermal conductivity, heat transfer coefficient, and the Nusselt, Reynolds, and Prandtl numbers, were examined for two scenarios with different temperature segmentation. In the first scenario, the process stream properties were assumed to be constant within temperature intervals defined by the supply and target temperatures (base case). In the second scenario, the process stream properties were considered to be constant within temperature intervals defined by the bubble and dew points (phase change case). Our study revealed the sensitivity of the process stream properties to temperature variations, demonstrating an increase in the density and thermal conductivity and a decrease in the enthalpy of the mixture with decreasing temperature. The energy targeting results showed lower pinch point temperatures and higher utility demands in the phase change case relative to the base case. This study demonstrates that the incorporation of phase change is vital to the design of a heat exchanger network.

The electrical energy is often produced with the help of diesel generators in isolated areas in the Saharan region. These generators require relatively a little investment, because it is generally expensive to exploit them due to the transportation (transportation to remote areas adds extra cost, significant fuel consumption and relatively high maintenance costs). Moreover, the electricity production by the diesel generators is ineffective and presents significant environmental risks. But these isolated areas have significant wind energy potential, which is good position for the exploitation of clean and sustainable wind energy. The use of wind-diesel power system is widely recommended especially to reduce fuel consumption and in this way to reduce system operating costs and environmental impact. The subject of this paper is to present the simulation of a wind-diesel power system. This system has a high-control strategy for the management of different power sources (wind, diesel, battery) that depends on weather conditions, especially wind speed values and the power demanded by the consumer load.

This paper presents a ray trace analysis in order to compare two integrated solar collectors. The first one is an ICS solar water heater based on symmetric CPC reflectors (ICS_SCPC), and the second one is an ICS solar water heater based on asymmetric reflectors (ICS_ACPC).ICS_ACPC is a new model which is designed to improve the optical performances of an existing system by increasing the quantity of absorbed energy. ICS_AFCPC consists of an integrated collector storage (ICS) solar water heater combined with an asymmetric compound parabolic concentrator (CPC) with two concentrating stages. The upper part contains two symmetrical parabolic sections with focal axes tilted at ±48° from the vertical plane. The lower part is constituted of three involute reflectors. Its cylindrical storage tank covers the triangle formed by the three involute part centers, and its geometric concentration is about 1:34. This design has a strong connection with a previous study, where an ICS system was designed and tested (Helal et al. 2011a). In this study, the ICS solar water heater based on symmetric CPC reflectors (ICS_SCPC) was modeled, realized, and experimentally tested. It consisted also of two concentrator stages: the first one, which was common to both systems, and the second one was a parabolic reflector placed in the exit aperture of the first stage. In both systems, the absorber of cylindrical design has a total stored water volume V_ab = 100 l.A ray-tracing model was developed via a code written on Matlab to simulate the reflection of the solar radiation on the CPC reflectors at different angles of incidence and compute the absorbed solar radiation distribution on the absorber surface. The obtained results, when compared with the experimented model, showed a significant improvement in optical efficiency and the distribution of the absorbed energy regarding the angle of incidence.

In this study, the thermoeconomic approximation is applied to the optimization of a case study of a geothermal hydrogen production and liquefaction system. The objective of this application is to minimize its overall product unit costs (electricity, hydrogen production, and hydrogen liquefaction). The approximation is based on the cost-optimal exergetic efficiency that is obtained for a component isolated from the remaining of the system components. The objective function that expresses the optimization methodology for each subcomponent of the system is developed. In the iterative optimization methodology, the variables, relative cost differences, and exergy efficiency with the corresponding optimal values are obtained. Exergoeconomically optimal values for total product cost flow rate, total cost fuel flow rate, cost of electricity, cost of hydrogen production, and cost of hydrogen liquefaction are calculated to be 1820 $/h, 274.2 $/h, 0.01908 $/kWh, 1.967 $/kg, and 1.095 $/kg, respectively, whereas the corresponding actual base case values are 3031 $/h, 290 $/h, 34.34 $/h, 0.02076 $/kWh, 2.091 $/kg, and 1.725 $/kg, respectively.

Thermal losses and Heating, Ventilation and Air Conditioning (HVAC) system play a significant role in thermal performance of buildings that is reflected in energy consumption and associated energy cost, respectively. There are different ways of solving these problems including retrofitting and conduction calculations of thermal protection of the buildings. However, the parameters affecting the energy performance of buildings should be addressed during early design stages. This is why energy modeling is a widely used tool for predicting energy use of buildings and applying various energy-saving measures. This paper presents a case study of modeling a school building’s energy behavior in Astana city considering its weather conditions and costs of energy sources. The use of three different systems, FCU, CAV, and mechanical ventilation with central heating, and RES application are considered and compared in TAS simulation software. It adopts a holistic approach to evaluate energy consumption, potential of renewable sources, thermal comfort, building orientation, and financial feasibility, as well as to make a set of recommendations toward improving energy efficiency and design solutions.

In present study, the performance of three configurations of the hydrogen production/refrigeration cogeneration cycle using biomass and solar energy sources is investigated and optimized with an economic approach. These configurations are such as solar-CO₂ transcritical cogeneration system (SCTCS), biomass-CO₂ transcritical cogeneration system (BCTCS), and solar-biomass-CO₂ transcritical cogeneration system (SBCTCS). The liquid flat-plate collector is employed as the source of energy. Besides, the dynamic model of solar radiation would be registered to search the system behavior during a day. Exergoeconomic and exergoenvironmental models are developed to investigate the thermodynamic performance of the cycle and to insist on the cost of products. In this study, hydrogen production rate optimal design (HPROD), refrigeration power optimal design (RPOD), and cost optimal design (COD) are considered for analysis and optimization. The exergoeconomic optimization results show that the sum of the unit cost of products (SUCP) in BCTCS is lower than other configurations. As a result, the BCTCS is determined as the most economic effective system among the three configurations. In BCTCS configuration, the SUCP decreased 9% when hydrogen production rate and refrigeration power are decreased from 1.817 lit/s to 1.754 lit/s and 6.425 KW to 6.103 KW, respectively. The evaluation of exergy destruction demonstrates the biomass burner and condenser have the higher exergy destruction in all configurations. In the three systems, the results indicate the total exergy destruction rate in the PROD case is higher than any other cases; however the investment cost rate in the HPROD is higher than the two other cases.

The hotels, which have a great potential in the building sector, are the structures needing effective energy management system with high energy consumption and cost. This study first includes the pre-energy audit to determine the necessity of efficient energy management system. In this study, the energy management indicators are defined depending on energy audit, and an analytical method has been developed to directly get effective energy management system for hotels. Hotels should be examined with two different approaches considering operational and structural requirements. To determine the cost of the business needs, the hotels must be evaluated in terms of structural aspects, comfort and environmental impacts. According to the analyses, when structural condition is taken into consideration, energy saving potential was found at 59.7% for m2. On the other hand, when bed occupancy was taken into account with operating cost, energy-saving potential was found as 43.8%. Similar analyses were made considering uninsulated consumption, and savings potential was found 36.6% and 27.3%, respectively. At the end of the study, some suggestions by defining indicators of sustainable energy management have been made.

Waste of energy in furnaces and cost fluctuations, especially the ascending trend of oil price which controls the energy market, have made the developing countries consider the processes to optimize energy consumption and improve industrial processes to decrease the production costs, and this approach has gradually been taken by semi-industrial countries as well. Nowadays, the modifications in consumption pattern and the ways of using energy have vital impacts on economic developments of the countries. Moreover, the hazardous influences of nitrogen oxides on environmental pollution have forced the designers of energy generator machines to think of procedures to lower the harmful gases as they often try to recognize the problematic sections inside combustion and control the temperature conditions in each section to restrain the production of harmful gases.The present paper uses porous environment to produce non-flame heat in furnaces, which has ultimately led into simultaneous optimization of energy and environmental factors in furnaces. The decrement of fuel consumption, increment in profitability, less space requirements, removal of NOx, and decrement of other toxic gases are among other advantages of such system in the production of heat.

In this study, nanosized tin nanoparticles are synthesized by chemical reduction technique. A facile strategy is also developed in order to synthesize the nanocomposite of tin (Sn) nanoparticles anchored on conducting graphene as an advanced anode material for high-performance lithium-ion batteries. The Sn nanoparticles obtained are 10–50 nm in size and homogeneously anchor on graphene sheets as spacers to keep the neighboring sheets separated. Detailed characterization of the resulting composite materials was performed using scanning electron microscopy and X-ray diffraction methods. The Sn/graphene electrode material exhibits a stable reversible capacity of 670 mAh g−1 after 100 cycles as the anode of lithium-ion batteries, indicating that the composites might have a promising future application in Li-ion batteries. The results have shown that Sn/graphene nanocomposite displays superior Li-ion battery performance with large reversible capacity, excellent cyclic performance, and good rate capability, highlighting the importance of the anchoring of nanoparticles on graphene sheets for maximum utilization of electrochemically active Sn nanoparticles and graphene for energy storage applications in high-performance lithium-ion batteries.

Energy consumption estimation for building energy management systems (BEMS) is one of the key factors in the success of energy saving measures in modern building operation, either residential buildings or commercial buildings. It provides a foundation for building owners to optimize not only the energy usage but also the operation to respond to the demand signals from smart grid. However, modeling energy consumption in traditional physical modeling techniques remains a challenge. To address this issue, we present a data mining-based methodology, as an alternative, for developing data-driven models to estimate energy consumption for BEMSs. Following the methodology, we developed data-driven models for estimating energy consumption for a chiller and a supply fan in an air handling unit (AHU) by using historic building operation data and weather forecast information. The models were evaluated with unseen data. The experimental results demonstrated that the data-driven models can estimate energy consumption for BEMS with promising accuracy.

Here we present a simple model of finite resource exploitation that is parameterized by initial cost ratio, a technologic and management index accounting for the rise of the exploitation cost with decrease of resource amount, plus another index accounting for the avidity of the market to the resource. The analysis showed that the model captures essential features of finite resource exploitation, namely, those concerning to oil exploitation. Scenarios for future oil exploitation based on parameters estimated from historical data are analyzed and discussed, as well some other scenarios of generic resource exploitation.

Wind power generation is one of the most effective ways to solve the electric power supply on islands. This paper presents a simple, reliable, and effective power regulating device for a small-scale island wind turbine, especially for the turbine’s protection against strong winds. The regulator consists of a rigid tail with an electrical control rotating the aerodynamic vane to yaw the rotor edgewise toward the wind direction in high wind speeds, an electric linear actuator, and a controller. Compared with the conventional mechanical vane applied in small-scale wind turbines, such a device possesses several advantages of a simple structure, which is easy to be manufactured and installed, high controllability, and increased reliability. The implementation of rotating the vane actively only depends on the generator speed by measuring AC electrical frequency and the output power by measuring two DC electrical quantities (i.e., voltage and current), and no mechanical sensors are needed. The regulator has been applied to a 15 kW wind turbine prototype operating on an island for more than 3 years. Field test results indicate that the regulator can effectively yaw the rotor out of the wind direction and its behavior agrees well with simulations. Such means of power regulating for small-scale wind turbines can be advantageously utilized compared to other mechanical or electromechanical methods.

In this paper, the production of electrical energy from photovoltaic systems (PV) was studied. Design, comparison, and economic analysis of the systems were performed. In order to carry out system designs and determine the technical and economical parameters of each system, HOMER program was used in the analysis. Belen (Hatay), Gelibolu (Çanakkale), Konya, Sinop, Kırklareli, and Karaman cities were selected as the design areas in Turkey. The system and levelized costs of energy were investigated for a load of 2500 kWh case annually, and the effect of capacity shortage fraction on the systems was examined. The systems were designed as grid-connected and off-grid (stand-alone) systems. Grid-connected systems were examined for cases with feed-in tariff. The levelized costs of energy vary between 0.267 and 0.367 $/kWh for PV in the case of feed-in tariff. According to the obtained results, it is determined that the grid-connected systems are more cost effective than stand-alone systems.

Here we present two techniques of commands: DTC (direct torque control) and DPC (direct power control), which are applied to the system for converting wind energy with storage. The wind generator used is based on a double-fed induction generator (DFIG), in which the stator is connected directly to the network and the rotor is connected to the network through the power converter. The Flywheel Energy Storage System (FESS), which is based on a flywheel, an induction machine (IM), and an electronic power converter, is associated with the wind generator via the DC bus. The two converters’ side DFIGs and the FESS are controlled by DTC. The three-level converter side electricity grid, which ensures constant DC bus voltage, is controlled by the DPC. The main goal of the direct control of these systems is to eliminate the block of pulse width modulation and loops by regulating internally controlled variables. The use of a switching table makes the system more efficient from a technical rather than an economic point of view.

Facing the major problem of water shortage, desalination is a strategic option for Algeria, which has implemented an ambitious program of desalination of seawater with a production capacity of 2260 million m3 (Metiche, Desalin Water Treat 14: 259–264, 2010).The desalination plant at Skikda, with a capacity of 100,000 m3/day, was initially operated in 2009 and is part of a large program that includes 13 seawater reverse osmosis desalination plants, with various capacities.However, the construction of desalination plants is inevitably associated with an environmental catastrophe caused by the vast discharge of brine and chemical reagents used in desalination (Ammour, F., Lounes, S., Houli, S., Kettab, A.: Environmental impact of desalination plant of Bou Smail (Algeria), 13th International Conference on Clean Energy, 2014, Fernandez-Torquemada et al., Desalination 182: 395–402, 2005).In this paper, performance evaluation carried out on a seawater reverse osmosis desalination plant located in the Sonatrach company industrial complex in the east of Algeria is presented. Recommendations are suggested to resolve these problems.

In this work, the design and sizing of a hybrid PV-electrolyzer-fuel cell system are proposed. This system is used to supply, in an autonomous manner, continuous power to a load. When solar radiation is available, the PV modules are used to generate electrical energy to supply the needed energy to the load. The excess electrical energy is stored under the form of hydrogen energy by using an electrolysis system. In cases where the energy generated by the PV does not meet adequately the needs of the load, the fuel cell using the produced and stored hydrogen provides the complementary energy.The design and sizing method is based on energy balance equations. Long-term characteristics of the system components are assumed constant. The optimum choice of the system component sizes is based on economic analysis. To this end, HOMER software is used.The method is applied to meet the University of Chlef energy needs. The energy needs are determined from the actual energy consumption of the University of Chlef over the last few years. Meteorological and radiation data from the Chlef region are also used for system sizing.

This paper presents an experimental evaluation of compact compressed air energy storage (CAES) system. The advantages of such a system are low cost, easy coupling with renewable resources (mainly wind energy), and high efficiency. While the system considered here is compact in size, the results obtained on the performance parameters, such as efficiency of energy conversion and expected electrical output, can be generalized for upscaling purposes. The main challenge with larger systems is the heat generated due to compression, which is not a major issue for the current system. Larger systems, however, enable operating at higher pressures, which means larger stored potential energy which in the case of 1 bar differential gave up to 13% higher kinetic energy.

The size of parabolic trough concentrators limits the mechanical sun tracking system’s solution. Generally, concentrating collectors use only one-axis or two-axis sun tracking; the sun’s position changes hourly; hence, the solar collector should be continuously adjusted in order to produce the maximum power. Single-axis tracking systems are considerably cheaper and easier to construct, but their efficiency is lower than that of the two-axis tracking systems. In this paper, we present a study that confirms the feasibility of a novel one-axis sun tracking system with reflector displacement in order to minimize the optical losses caused by the cosine effect in the small parabolic trough concentrators. Optical and thermal simulations are performed to prove the efficiency of the novel system by comparison between the two cases, with reflector displacement and the ordinary system—the results are very interesting. We have proposed a novel sun tracking system with a good annual efficiency.

An experimental investigation is conducted on crystal growth formation of R134a with additives, as phase change materials (PCMs), for cooling applications. The experimental investigation focuses on the crystal growth time and the characteristics of the formed PCMs. The formation of refrigerant clathrates at different operating conditions is investigated due to their potential use in active and passive cooling applications in electronic and residential cooling. The PCMs are made using R134a clathrate and distilled water with different refrigerant proportions and five different additives. The additives are used to improve the clathrate formation time and the crystal growth propagation under direct contact heat transfer mode. PCMs are formed in glass tubes and their crystal growth of freezing onset and crystal growth formation time is recorded at different operating temperatures. Refrigerant R134a percentages of 25%, 30%, 35%, and 40% are used to form clathrate. For the additives, ethanol, sodium chloride, magnesium nitrate hexahydrate, copper, and aluminum are used. PCMs are formed using controllable constant temperature water bath. The low crystal growth formation time showed that the PCM requires low energy input to change its phase, whereas more time shows PCM takes more energy to transform. A comparative study is conducted to compare the crystal growth formation time for different PCMs. R134a refrigerant clathrate without any additive is used as the base PCM. The results showed that metal additives reduced the crystal growth formation time, ethanol and sodium chloride increased the crystal growth formation time. Magnesium nitrate hexahydrate maintains it the same as that of the base PCM. It is also found that the freezing time depended not only on the thermal properties of the used additives but also on their ability to mix homogeneously in the refrigerant clathrate. Furthermore, some additives are considered to be very useful in enhancing the crystal growth formation of the clathrate with a stabilized crystalline structure. PCM with high latent heats over narrow temperature ranges are desirable as they offer high energy density at uniform temperatures applicable for cooling applications.

The present work introduces a transient irreversible model of a heat-driven refrigeration plant that is driven by solar energy. The model consists of a solar collector, a refrigerator with three finite-size heat exchangers, namely, the evaporator between the refrigeration load and refrigerant, the condenser between the refrigerant and the ambient, and the generator between the solar collector and the refrigerant, and finally the refrigerated space. The total thermal conductance of the three heat exchangers is fixed. A mathematical model is developed. It combines the classical thermodynamics and mass and heat transfers principles. The numerical simulation is made for different operating and conceptual conditions. A global minimizing time optimization, to reach a prescribed cold-space temperature is performed in order to reach maximum performances. Appropriate dimensionless groups were identified and the generalized results are reported in dimensionless charts. The collector temperature presents major influence on the conceptual and functional characteristics compared to the stagnation temperature influence.

Clean energy technologies are beginning to receive attention in Nigeria to offset increasing greenhouse gas (GHG) emissions. These emissions are associated to the wide use of small-scale fossil fuel-powered generators by about 55% of its 180 million people, yet to be connected to the grid. While a large hydropower potential exists in Nigeria, even above the total electricity demand of the country, by 2013 this technology only accounted for about 32% of the total installed generation capacity connected to the grid. Previous studies have limited results in terms of technical, economic and environmental evidences that can drive choices towards small hydro and other clean energy projects for users and technology providers in Nigeria. This study uses the RETScreen Software to analyse the technical, economic and environmental aspects of a proposed mini-hydropower plant on Tuwan River, to supply part of the energy needs of Tuwan Agribusiness Resort (TAR) located in Madakiya District, a rural community in Kaduna State, Nigeria. The volumetric flow and gross head of the chosen river were measured and the power generation system design yielded a 21-kW power output, capable to partially offset the present use of diesel generators and achieve a 307.4 tCO₂-equivalent GHG emission reduction. The financial analysis showed an attractive internal rate of return (IRR) of 68.1% and net present value (NPV) of 568,178 USD (11% discount rate), owing to the high potential of the project to attract grants and tax rebates, which were put into consideration in the financial analysis. This study is important for Tuwan Agribusiness Resort, an agribusiness service provision outfit with a potential to create over 1000 jobs when fully operational.