Sustainable Development with Renewable Energy

The energy sector, especially in Europe passes a very hard period. Russia’s unprovoked aggression against Ukraine just exposed a large degree of dependence on fossil resources from Russia. The greatest dependency is in the natural gas sector, but also in the oil, coal, or nuclear products sectors. In reaction, European Union release new proceedings called RePowerEU to get rid of dependence on Russia and other hostile countries and achieve climate neutrality by 2050. Renewable energy sources have a key role in this energy transition, typically because of no operational commodities, or simply safely obtainable commodities for the operation of these resources. Agrivoltaics as part of the whole photovoltaic sector are in many countries tested in pilot projects and definitions are slowly implementing into national policies. Different countries are trying to implement agrivoltaics in their policy in different ways, and several pilot installations are helping each government to understand the technology. Agrivoltaics has many forms and types. It can be combined with permanent cultures like berries, apple farms or conventional agriculture. After many years of testing agrivoltaics around the world, the biggest barrier is the legislative and permitting process. This paper highlights key barriers to agrivoltaic systems and describes ways how to unlock them.

The paper presents an approach for short-term planning of the development of distribution networks in the presence of decentralized energy sources (DES). The approach consists in developing planning strategies with the aim to control the electrical network and in compiling a number of scenarios to each strategy. The stages of construction of the decentralized sources and the possibility of changing the electrical loads are taken into account. Calculations of the parameters according to the selected one or several criteria for the different scenarios of each strategy allow to choose the optimal one from the whole number of 196 developed scenarios. This is an actual problem in planning the distribution networks with connected decentralized energy sources. The paper presents the developed calculation modules, together with the specialized software for the simulator of the modes in the electrical networks. The compiled algorithm allows to determine the optimal scenario for short-term planning of a distribution network with set loads and decentralized energy sources, while taking into account the most significant influencing factors and limitations. It is not possible to point in advance for a particular branch of a distribution network at the optimal scenario for a given strategy by a chosen criterion. Therefore, it is necessary to perform the calculation procedures by the proposed methodology and software.

The paper studies the influence of the grounding mode of the neutral on the reliability of active-adaptive medium voltage distribution networks. The selection of an appropriate type of reliability for evaluation is justified, with the aim of achieving comparability of the results for different grounding modes of the neutrals. A simplified approach for assessing structural reliability and a methodology for determining the parameters of operational reliability are presented. The results from the performed calculations for the different modes of neutral grounding are compared and conclusions are drawn about the ways of improving the reliability of the actively adaptive electric grids.

This work evaluates the technical feasibility of installing photovoltaic solar panels for homes in the city of Huancayo, Peru. For this, variables such as solar radiation, orientation, angle of inclination and electrical power were taken into account. The development of the study was carried out in the renewable energy laboratory of the electrical and electronic engineering Faculty of the National University of Central Peru, which is located in the city of Huancayo. The prototype used was model YI6R-30P, polycrystalline silicon at 30 W and 12 VDC. With the objective of optimizing the variables of the study for the efficient use of the solar panels that are being used in the present work. The data collection was evaluated in 3 consecutive months of this year, where the electrical power generated according to the solar radiation obtained during each month, with an orientation (0°N and 45°NE), and angle of inclination has been measured (13th and 16th). In conclusion, the most efficient design is: 7 h of high solar radiation, with an inclination angle of 16°, oriented towards the North-East, and electrical power of 20 W.

One of the wastes generated in the tanning industry is hide fleshing, which contains 40% of animal fat, currently being deposited in landfills. The objective of this work was to study the catalytic capacity of dolomite in the gasification of this waste. The tests were carried out in a downflow fixed bed reactor using steam as gasification agent and used as bed of particles: alumina, dolomite and a mixture of these two materials. Tests were carried out at 750 and 800 °C and the gas obtained was quantified and analyzed by gas chromatography. The results showed that dolomite improves the performance of the gasification process, with an increase in carbon and hydrogen conversion efficiencies, cold gas efficiency and dry gas yield. It was also possible to verify the catalytic capacity of this material in the cracking of hydrocarbons and its potential to promote the production of H2. In addition, the use of the mixed bed improved the results of the gasification parameters obtained at 800 °C without compromising the degradation of the dolomite verified at higher temperatures.

Portuguese agriculture holds significant importance in the country's culture and economy. While it has embraced advanced production methods, waste management remains a challenge. However, agro-wastes offer a promising solution through anaerobic digestion, contributing to waste reduction and promoting sustainable practices. This study focuses on the energy potential of two specific agro-wastes: wine vinasse (WV) and pig slurry (PS). The results indicate that both residues can be effectively utilized for biogas production. WV demonstrated a specific methane production (SMP) of 1.03 NL-CH4/g-VS, while PS showed an SMP of 0.57 NL-CH4/g-VS. When converted into electrical energy, these findings translate into energy production potentials of 3.00 kWh/kg-VS and 1.52 kWh/kg-VS for WV and PS. Alternatively, direct burning of the biogas for heating purposes can generate 7.04 and 3.56 kWh/kg-VS for WV and PS, respectively. Although the energy generated may not fulfill the entire industry's demand, it significantly reduces dependence on fossil fuels. This green and sustainable alternative offers cost savings and effective management of agro-waste. By harnessing the energy potential of WV and PS, industries can make strides toward a more environmentally friendly and economically viable future.

The present research work aimed to evaluate the effect of different treatments composed of solid sediments, water, and biomass on the production of methane (CH4) gas by anaerobic biodigestion. Concerning the methane production, three treatments were carried out by alternating the variables with biomass (sugar cane, sugar cane/banana peel, and banana peel). The evaluated time of digestion was 14 days. The gas chromatography was employed to measure the concentration of the methane gas generated in the bioreactors. The best results were with bagasse de sugar cane with the banana peel as biomass produced less than CH4 (3.78%) and more than CO2 (54.31%) compared with the sugar cane bagasse. The obtained results of CH4 (72.98%) and CO2 (13.59%) included alternative factors such as temperature and digestion time important for higher production. In addition to this, a comparison of the production potentials of each biomass was used in the experimentation, having as a result that the sugarcane bagasse is better with 796.78 mL/g of methane per month compared to the banana peel biomass, which was 9.36 mL/g of methane monthly.

At COP 26 (Conference of the Parties 26th), held from October 31 to November 12, 2021, in Glasgow, an agreement was reached that Scotland is committed to reducing the rate of carbon emissions and addressing climate change. A similar meeting, COP 27th, occurred from November 6 to November 18, 2022, in Sharm El-Sheikh, Egypt. The main objective was to limit the projected global average temperature increase, estimated to reach 2.7 °C by the end of the twenty-first century. Indonesia is actively participating in addressing global climate change. To address this issue, pico hydro turbines are considered a viable option for implementation, especially in remote communities. The undershot water wheel is one type of pico hydro turbine technology deemed suitable due to its believed ease of design, installation, operation, maintenance, and cost-effectiveness compared to other types. Comprehensive studies on comparing curvature in undershot turbine blades have yet to be extensively discussed. This study focuses on determining the optimal blade curvature variations for undershot turbines to achieve maximum efficiency. The study includes variations of blade curvatures at 180°, 160°, and 140°. The numerical methodology employs the ANSYS application to simulate the flow around the designed turbine blades. Based on the study results, it can be concluded that the optimal blade curvature obtained numerically is 140°, with an efficiency of 37.15% for the numerical analysis.

The increasing rate of energy consumption, driven by population and economic growth, has prompted countries to shift towards alternative energy sources due to the finite nature and environmental impact of fossil fuels. The 26th and 27th Conference of the Parties of the United Nations Framework Convention on Climate Change has focused on reducing carbon emissions and curbing global temperature rise. In remote areas of Indonesia, such as Fatoin Village in East Nusa Tenggara Province, access to electricity remains limited, with approximately 1.95 million people needing more power. Remote areas are characterized by low population density, inadequate infrastructure, limited economic development, and reliance on agriculture or fishing as the primary livelihood. However, connecting these areas to the national grid would result in high electricity prices per kilowatt-hour. In order to overcome that, a hydroelectric power plant is proposed that uses pico hydro turbines, specifically undershot waterwheel technology. Undershot waterwheels are considered suitable due to their simple design, easier installation, and lower operational and maintenance costs than other turbine types. A comprehensive study has been conducted to determine the optimal blade angle for the undershot waterwheel, focusing on achieving maximum hydraulic efficiency. Using numerical methods, the study compared different blade angles (180°, 175°, 165°, 150°, and 135°). The numerical method utilized the ANSYS application to simulate the flow and collision with the designed turbine blades. Based on the numerical analyses, it was determined that the optimal blade angle is 180°, with an efficiency of 40.1%.

A poorer combustion quality of biodiesel compared to diesel fuel has led to a low cylinder pressure of compression ignition engines, increased fuel consumption, and reduced fuel efficiency. Most of the biodiesel boiling point curves are almost flat without slope. In fact, fast evaporation of fuel may lead to more intense heat release if a higher percentage of the fuel is mixed with air to form a combustible mixture. An increasing boiling curve is beneficial for good fuel ignition and combustion in the cylinder. In this study, the coconut oil methyl ester (CME)-palm oil methyl ester (POME)-diesel blends boiling curve is investigated. The fuel samples were prepared and characterized by distillation curves and gas chromatography. CME was produced by the transesterification method and the result shows fulfills ASTM 6751 and EN 14214 standards, except for the CME flash point that lower than its standards. However, a low flash point has the benefit of reducing the ignition delay which can improve the ignition process and combustion. The result also shows CME is more volatile compared to POME. The blending of diesel to POME has improved the distillation of the fuel behavior. In order for an ideal fuel distillation curve, the maximum blending CME into diesel is 20% (DCME20). PCME50 and PCME45 show a good trend of the distillation curve for improvement of biodiesel volatility.

Electrical power systems are shifting to be more intelligent, creating smart grids that employ a widespread bi-directional communication system for monitoring the grid status and improving grid assets management. This chapter presents a case study for energy community data monitoring, which aims to provide real-time data monitoring using internet of things based hardware-in-the-loop approach. The information is received from several internet of things devices connected to the different loads within the energy community. The acquired data will be transferred in real-time into the energy community digital model; therefore, it will be able to provide real-time data monitoring of different metric quantities of the community thus enhancing the energy operations management. The case study presented in this paper demonstrates the potential of internet of thing and hardware-in-the-loop techniques for real-time data monitoring and the study of several operation scenarios under real-world conditions. The data monitoring is performed for two hours duration, also, a demand response event is implemented to enhance the voltage profile of the community.

Drying is one of the processes that can be used to reduce agro-food industry wastes. The study of drying kinetics and the factors that affect it is essential to optimize the process and obtain a good quality and sustainable product promoting circular economy. Considering the producers interest, this work focused on the drying of blueberries and raspberries. The main objective was the mathematical modeling of the drying curves of these fruits to allow predicting the process evolution. Laboratory drying tests were carried out under different conditions, monitoring the moisture content of the fruits. The chemical properties of the dried products were evaluated to see how different conditions affected them. Thin layer mathematical models (Newton, Henderson and Pabis, logarithmic and two-term exponential) have been adjusted to the experimental data through a nonlinear regression analysis. The mathematical models obtained were validated by comparing their results with experimental data. For this purpose, the coefficient of determination (R2), the mean absolute error (MAE) and root mean square error (RMSE) have been used. All thin layer models tested show good fitting ability with the experimental values; however, the Henderson and Pabis model and two-term exponential model presented the best fit for both products.

This chapter challenges the traditional urban housing identity in Egypt by transferring complex urban microclimate details into urban planning/architecture design action to generate housing typologies in hot arid regions that use appropriate materials to maximize thermal resistivity. The presented housing typology is based on a decade of microclimate research in Egypt revealing court-yarded cluster housing typology. Assessment of Urban, Building, Material, and Renewables dimensions (UBMR) neighborhood passive scenarios in New Aswan included pedestrian thermal comfort, solar irradiance on ground levels, solar Radiant Exposure (SRE) of the cluster courtyard walls, energy consumption, and decarbonization. The usage of Compressed Earth Blocks (CEB) bearing walls for the building envelope completed the urbanism passiveness picture, revealed compliance with the Egyptian energy efficiency code, and significantly reduced annual cooling energy consumption by 10 kWh/m2 and carbon emissions by 4 kg/m2. Coupling the urban building geometrical masterplan sketching and vegetation adjustments offers reduced heat gain of 24.66% at peak time (2 PM) in comparison to parcel planning. ENVI-met analyzes microclimate using weather data auxiliary tools to extract assessment parameters for UBMR dimensions. It is argued that both urban Solar irradiance (IRD) and building SRE tripled with Physiological Equivalent Temperature (PET) are essential to conserving energy and decarbonizing the environment.

The paper focuses on the potential application of supercritical CO2 (sCO2) power cycle for waste heat-to-power systems in cement industries. The reference power cycle is based on the CO2OLHEAT (G.A. 101022831) European project, which includes the pioneering implementation of a 2 MW demonstration plant in a relevant environment. The paper provides an overview of the key technologies and processes in the cement production sector within Europe. It emphasizes the successful recovery of waste heat without compromising industrial operations. The analysis encompasses five relevant countries in the EU region, each of them characterized by distinct features such as cement production and export, power generation energy mix, and geographical considerations. The analysis is referred to the year 2019, representing the most up-to-date data obtained from specific database sources, which allowed a differentiation based on technological classes of cement production rather than specific cement plants. Therefore, a generalized approach has been adopted to consider various scenarios of waste heat recovery based on available thermal energy and temperature ranges, taking into account specific requirements, limitations, and possibilities in terms of thermodynamic, economic, geographical, and political constraints.

Organic Rankine Cycle (ORC) systems have received growing interest due to their potential applications in renewable energy power plants (solar, geothermal, biomass) and waste heat recovery applications. Despite being a consolidated technology, they usually suffer from low plant efficiency connected with their thermodynamic constraints (low/medium temperature of the available heat source). Therefore, to not penalize their performance even more, particular attention has to be paid to a good design of key components like the turbine. Most of the turbines applied are axial or inward-flow radial machines derived from other applications. This paper compares a two-stage inward and an innovative multi-stage centrifugal turbomachine designed for the same case study. Both machines are designed and analyzed by using 3D CFD steady state simulations. Performance and main pros and cons are highlighted for both machines working with pentane.

Organic waste, mainly fruit waste, has become a global problem, even more so in developing countries, because they need current policies for its proper collection. This research used pear remains in microbial fuel cells or single-chamber bioreactors to observe the potential of this substrate, using zinc and copper electrodes. The maximum results obtained from voltage and electric current were 3.748 ± 0.261 mA and 0.101 V on the ninth day, operating at a pH of 4.62 ± 0.12 and with an electrical conductivity of 86.825 ± 4.726 mS/cm. While the Rint. of the cells found was 61,795 ± 8691 Ω, whose displayed power density was 300,932 ± 13,419 mW/cm2 for a current density of 6232 A/cm2. In the final stage, the MFCs were connected in series, managing to observe a value of 3.03 mA of electrical current and 2.59 V of the peak voltage. This research gives the first insights into using this fruit as fuel in microbial fuel cells so that the future can scale and become more commercial for applications that help entrepreneurs and citizens.

The continuous consumption of fossil fuels has increasingly become a threat to the environment. This is mainly because of the harmful emissions released during their combustion and thus the need for finding applicable solutions. Among these, the use of H2 blended CH4 fuels has proved promising however, there are some drawbacks due to the difference in their combustion characteristics; necessitating the need for further research to obtain a clear understanding of their combustion behaviors. Therefore, this study aims to experimentally examine the effect of equivalence ratios (0.5, 0.7, 0.9, 1.1, 1.3) and fuel composition (0–10%) H2 enrichment to CH4 on temperature distribution near the combustor walls while varying the swirl intensities (30°, 60°). Three K-type thermocouples stationed at a height of 91, 196 and 277 mm along the vertical axis of the combustion chamber and extending 3 mm from the inner walls are used to measure the temperatures. Results show a similar trend at both intensities of temperatures increasing with decrease in equivalence ratio but slightly higher at a swirl intensity of 60° than at 30°. Furthermore, temperatures decrease with height towards the combustor exit. For fuel composition, temperatures at 10% H2 addition are higher than that at 0% H2 and the trends obtained are different. At 10%, temperatures rapidly decrease with an increase in height for both intensities while at 0% temperatures at 91 and 196 mm are nearly constant but rapidly decrease towards the combustor exit which can be attributed to the different flame shapes attained.

The current standards for controlling pollutant emissions require that diesel engine vehicles be equipped with increasingly complex and efficient exhaust gas aftertreatment systems. One of these systems is the so-called Diesel Particle Filter (DPF) for retaining combustion polluting particles. To prolong the life of this system, which is normally quite expensive, there are precautions that must be taken by the driver and the most important consists of not interrupting the regeneration cycles, during which the retained particles are turned into ashes so as not to clog the filter. This paper presents a system that uses a proprietary algorithm which adapts to the available information that the vehicles provide through On-Board Diagnostics (OBD) and when no specific information about the DPF is available, uses fuzzy logic to process other data to detect the need of a regeneration and advise the driver about the correct procedures to extend the useful life of the DPF. The system outputs to an integrated display if a regeneration is being performed, the DPF state of health and a prediction of when the next regeneration will happen. Amongst extensive tests, two were selected to be discussed where a regeneration was detected and cancelled and another test where a faulty DPF was used.

Energy usage and climate change are 21st-century challenges. The main cause of climate change is greenhouse gases (GHGs) which are mostly produced by burning fossil fuels. Therefore, effective solutions for new urban areas are required to mitigate climate change impact and to achieve a balance between different sustainability dimensions. Thus, this research investigates the assessment of applying a new generation of Egyptian cities that possesses an urban identity and architectural character, which is called; the 5th generation of Egyptian cities. An outdoor simulation is performed using ENVI-met software to assess the mutual effect on buildings and street canyon conditions, whereas the street canyon considers urban details, and identifies various environmental sustainability measures. This work shows with courtyarded clustered housing with CEB wall material is more efficient as the simulation results show a reduction in air temperature by (0.71%), mean radiant temperature by (3.91%) as a maximum value in the peak day hour, and better human thermal comfort PMV by (4%) as a maximum value at hours from 10 am to 5 pm and by (2.8%) as an average value all day. An indoor simulation is also applied using Design-Builder software and it shows that there is an average reduction in energy by (5.5%) and CO2 emissions by (3.2%). Also, Thermal comfort (PMV) is better by (18.6%) as an average value.

The transportation electrification is growing fast, especially with batteries and electric vehicles (EV) decreasing prices. Based on the growing number of EV close to end-of-life, a topic became popular, second-life batteries (SLB). SLB are batteries removed from EV when their energy and power density degraded below required level but are still performant enough for other applications. The transportation sector is trending towards electrification, which means a significant change to used batteries’ availability for energy storage systems. Such change has two sides, clean transportation, and battery discard’s increasing volume. SLB also have come in response to the growing number of discarded batteries from expanding EV industry. The objective of this study is to analyse the European scenario for second-life batteries and the policies related to this mater. Data was collected from each European country on sales, collecting and recycling and the current legislation and proposed ones were carefully analysed. Even though there is no reuse data, the collection data of waste batteries is very low, being below target in some countries. Europe has no regulation related to SLB, and the current regulation has many grey areas as it is not adapted to current technology, characteristics, and volume of batteries in the market. Directive 2006/66/EC aims to minimize environmental impact by promoting waste battery recycling and reuse. However, this regulation is outdated and inefficient by today's standards. The EV market growth is leading to fast accumulation of retired batteries. Reusing batteries and extending its life expectancy can reduce environmental impact and improve economic advantages.

In the last century, the considerable increase in global population, industrialization, and fossil fuels consumption, has raised serious issues of environmental sustainability. One of the most adverse environmental impacts is the high level of greenhouse gas (GHG) emissions, the main responsible for the current global warming. In line with its commitments under the Paris Agreement, in 2019 the European Union (EU) adopted an ambitious strategy for reaching climate neutrality by 2050: the European Green Deal. Its main goal is to achieve a competitive resource-efficient economy with no net GHG emissions. In this context, it is imperative for policy makers to adopt public policies to reduce the carbon footprint, namely an effective environmental taxation policy—a key tool for governments to achieve economic growth along with environmental sustainability. This research study proposes to analyse the relationship between environmental taxes, also known as green taxes, and the environmental performance of EU countries, measured by CO2 emissions. By employing a panel data model, the study concludes that countries with higher green tax revenues also exhibit better environmental performance, characterized by lower emissions. Furthermore, the results suggest that environmental taxes only have a negative impact on CO2 emissions once they surpass a certain threshold value.

The impossibility and lack of accessibility for several households in Europe to resort to efficient heating and cooling technologies in their homes or to carry out energy rehabilitation in buildings has been a growing concern, not only in the European Union, but also in many Member States. These households that are energetically vulnerable belong to the statistics of the phenomenon identified as energy poverty. Multiple factors justify the growing concern about this problem within the European Union, either due to the need to assess the consequences of the liberalization of energy markets on the most vulnerable consumers, or due to the creation, exposure and identification of situations of poverty, social exclusion, health problems public health, decrease in comfort and living conditions. These factors tend to influence the country's macroeconomic outlook to the extent that they undermine energy policy options, reducing their efficiency and making it difficult to implement energy policies that are more environmentally friendly and capable of facing the challenges of climate change. Since the built environment is the largest consumer of energy, the fight against energy poverty should be encouraged in this sector due to the impact it may have on the country's socioeconomic indicators.

Jatropha curcas L. is a tropical woody shrub that has a big potential for biodiesel resources. The Crude Jatropha Oil (CJO) content is about 30–40% in the seed, and 40–50% in the kernel. CJO is obtained from the extraction process of dry seeds by mechanically and chemically. Mechanical extraction by pressing is easier and cheaper since does not require a complicated technology. The aims of this research were to analyse the seeds quality and CJO based on various hybrid of J. curcas as a source of biodiesel. The materials used were dry seeds from 4 genotypes of J. curcas hybrid plant from Kedung Pengaron, Pasuruan District, East Java Province, namely G5-A, G5-B, G6-A and G6-B. This research consisted of 2 steps, started from determining the J. curcas L. seeds quality (water and oil content) followed by CJO production and oil analysis (acid number, free fatty acid (FFA) content, saponification number, ester number, and water content). Completely Randomized Design with 3 repetitions was applied to obtain the data. The different genotype of J. curcas L. did not show significant differences on the seeds oil content, but showed significant differences on the water content. The different genotype of CJO was also significantly different in what concerns the acid number, FFA, and water content. The genotype G6-A of J. curcas L. plant can be considered to be developed as a promising breed based on the property indicators as a source of biodiesel.

Achieving sustainable energy development will require strategic planning and monitoring the effects of selected strategies. The development of a comprehensive system of indicators and a sustainable energy index could therefore be useful to assess both the current state and the progress made towards achieving sustainable energy. The article concerns sustainable energy development at the regional level and focuses on the most important element of sustainable energy development, which are renewable energy sources (RES). Indicators describing the potential of individual RES in regions, the actual use of individual RES and the institutional dimension in the field of supporting the use of RES were taken into account. The aim of the article is a comparative analysis of the level of sustainable energy development of Polish regions in relation to the potential, use and institutional support of renewable energy sources. Taxonomic methods were used: SAW and TOPSIS. The purpose of the research in the methodological layer is to compare the results obtained with the use of SAW and TOPSIS methods and to verify the goodness of fit of both methods. Clustering was also carried out to identify similar regions in the implementation of the concept of sustainable energy development.

The adoption of alternative fuels and electrification represent promising and efficient solutions to decrease the environmental impacts of the transport sector and mitigate climate change. For this purpose, updated analyses on the diffusion of cleaner transportation options and evaluation of their corresponding environmental effects are fundamental factors for policymakers and responsible investors. In this framework, the present work aims at investigating the spread of alternative fuel passenger cars in Italy, Portugal, and the European Union during the last 15 years. According to the literature, Italy and Portugal present the slowest deployment rate of battery electric vehicles (BEVs) but offer among the highest gas emission decrease potential in the EU-27 area. The analysis focuses the attention on BEVs to promote the transition towards sustainable and smart transport, and reduce the dependence on fossil fuels. Results highlight a similar growth rate of BEV passenger automobiles in the three investigated areas, despite the noticeable differences in the car fleets and shares of alternative fuel vehicles. Particularly, an exponential trend characterizes the diffusion of electric passenger cars in the last few years. Afterwards, the paper evaluates the yearly electric consumption and the corresponding carbon dioxide (CO2) and greenhouse gas (GHG) emissions of the circulating BEV fleets, considering the recharging process and the energy mix for electric production. The investigation demonstrates that electric mobility reduces harmful emissions and has the potential to significantly mitigate the environmental impact of the transport sector, if coupled with an increase in the exploitation of renewable sources.

The water supply is vital for the development of human activities. However, wastewater generated must be adequately treated or reused, so applying an adequate and environmentally friendly purification method is necessary. In Ecuador, Libertador Bolívar coastal community presents frequent overflows of wastewater from the stabilization ponds due to mass tourism, being a challenge for the administrators of the local sanitary network. This research aims to carry out a geomechanical characterization of the soils of the sector through field studies and laboratories to obtain an optimal location of green filter systems that reduce contamination by wastewater discharges that generate an environmental problem. The results showed that the lithology of the area (sands with a high clay content) allows adequate filtration to remove and reduce the concentration of pathogenic microorganisms in the pre-treated waters in the stabilization ponds. Simultaneously, a timber species (Guadua angustifolia) was proposed due to an affinity to humid environments, accelerated growth and final use as building construction materials. According to these results, an approximate area of 15.46 ha is suggested around the stabilization ponds for the maximum reuse of residual water, contributing to the sustainable development of the affected population and generating an economic resource in the sustainable use of timber resources.

Wastewater treatment is a responsible practice in administrating and managing water resources in populated areas. In Libertador Bolívar (Ecuador), due to the overload of the water treatment system, the wastewater disposal capacity constitutes a threat to both soils and water bodies in the surroundings, as well as the use of unconventional treatment systems (e.g. green filters), based on solutions inspired by nature constitutes a valuable resource to avoid environmental degradation in the area. This study aims to reuse wastewater from stabilization ponds, using green filters to use their nutrients, promoting reforestation in a circular economy. The results showed an average elimination of the biochemical oxygen demand (BOD5) of 87.11%, while the removal of coliforms does so at 87.23%, at a depth of 90 cm. Based on these results, the system complies with Ecuadorian environmental regulations regarding the quality of water resources. Additionally, from an economic standpoint, the system is feasible for the community with a significantly low annual cost per inhabitant (8 US Dollars). Finally, the pilot system of green filters substantially reduced the pathogenic microorganisms of the stabilization ponds, considering a usable resource for reforestation with endemic species of the area and promoting the circular economy.

One of the main sources of water and soil pollution is the release of complex effluents, such as those from the wine industries and research on the degradation of their contaminants is quite a challenging task. The winery wastewaters come from different stages of wine production and their characteristics are highly variable throughout the year. Advanced oxidation technologies such as the Fenton process offer suitable solutions for recalcitrant compounds removal in this kind of wastewaters. Since H2O2 is typically reactive at room temperature and pressure, no energy input is needed for the Fenton process, making it an attractive and a low-cost treatment method. In this study, the Fenton process was applied to treat real winery wastewaters from the bottling stage period. The impacts of Fe2+:H2O2 ratio and H2O2 concentration were studied closely. The results showed that the highest and lowest efficiencies for chemical oxygen demand (COD) removal were 72% and 34%, respectively.

The main objective was determining the in vitro tolerance between Trichoderma asperellum and the fungicide Fitoklin. Therefore, the effect of the fungicide on germination and the growth of T. asperellum was evaluated. The evaluated fungicide concentrations were 262.5, 350.0 (field dose), and 437.5 mg/L. The results showed that none of the three concentrations inhibited the germination of T. asperellum spores since the growth and pigmentation characteristic of the fungus occur. On the other hand, as the concentrations of the fungicide increased, the growth of the fungus was inhibited; however, it was able to tolerate the fungicide, which according to the existing literature, T. asperellum may express genes of ABC transporters and oxidoreductases, which play an essential role in the degradation of pesticides. Therefore, it is concluded that, in vitro, T. asperellum can be tolerant with the fungicide Fitoklin, which can be considered if it is to be applied jointly in integrated pest management (IPM), which, in turn, represents a sustainable way with the environment. which can be considered when applying them together IPM, which, in turn, represents a sustainable way with the environment.

In tannery industries, before the tanning process, the hides are preserved through a curing stage. This involves applying 40–50% of common salt (NaCl) based on the fresh weight of the hide. One of the byproducts of the curing stage is contaminated salt, which is usually landfilled. In this work, the reclamation of this waste was achieved through iron-driven electrocoagulation of salt-derived brine (SdB) using iron electrodes. A current density of 371 A·m−2 was applied for 16 min, yielding 88% removal of total organic carbon (TOC). The upscaling of this process requires suitable materials. Given that NaCl is highly corrosive to metal structures, this work investigated the corrosion resistance of different metals and alloys (aluminium, brass, carbon-steel, copper, AISI 304L and AISI 316L stainless steels) when exposed to SdB. The corrosion resistance was evaluated using different electrochemical techniques, including polarisation curves and electrochemical impedance spectroscopy (EIS). These measurements were made after immersing the metallic alloys in SdB for one hour and one month. The corrosion resistances of the six metals and alloys, ranked from highest to lowest, were as follows: AISI 316L > AISI 304 > aluminium > carbon-steel > brass > copper. This research provides valuable insights for future pilot-scale researchers and up-scaling efforts. By improving the circularity of the tannery industry and enhancing their competitiveness against conventional treatments, this work contributes to the advancement of the tannery industry.

Energy is a vital issue for countries, their economies and to achieve sustainable societies. The use of fossil fuels, energy resource scarcity, security issues and prices instability are major problems in nowadays energy systems. Energy consumption is for that reason very important and should be studied. The evolution of energy consumption in Portugal and in the EU27 is very similar for transportation and industrial sectors. Transport and industry are the main contributors to energy consumption in Portugal. In households, the main source of energy is electricity and in industry’s sector main sources are electricity and natural gas. Concerning the transport sector, main energy sources are gas oil and diesel oil and motor gasoline. The emissions of main GHG (greenhouse gases) due to electricity in energy consumption are equal to 5099.86 kt CO2, 0.311 kt CH4 and 0.24 kt N2O which corresponds to 5174.0 kt CO2e.

The Virtual Power Plant for Interoperable and Smart Islands (VPP4Islands) project aims to improve the integration of renewable energy and establish smart energy communities through shared capacity hybrid storage technologies. This study investigates regenerative hydrogen storage in two scenarios in Formentera, one of Spain’s Balearic Islands. The first scenario involves a single, grid-connected culture building with an annual electricity consumption of 51,183 kWh. The second involves an energy community consisting of the same culture building, two schools, and a radio and youth center, with a collective annual electricity consumption of 148,391 kWh. A 4-kW fuel cell, a 7.2-kW input electrolyzer, a 14.4-kWh lithium-ion battery, and a 3-kg hydrogen tank are modeled for both scenarios. HOMER Pro software was utilized for technical and economic optimization by minimizing the levelized cost of electricity (LCOE) and net present value (NPV). SimaPro 9.3 was used to assess the environmental life cycle impact of the optimized electricity mix serving the load in each scenario. The results show that 10 kWp (kilowatt peak) of photovoltaic (PV) capacity is needed for the first scenario, and 54.2 kWp for the second. The optimized community system achieved an LCOE of 0.154 €/kWh, a 48.6% reduction compared to grid electricity alone. Carbon emissions also improved to 174 gCO2-eq/kWh at the community level, a reduction of 47%. However, the ecotoxicity impact group increases, primarily due to the PV manufacturing and installation phases. The study highlights the technical, economic, and environmental advantages of deploying hybrid regenerative hydrogen storage systems at a community scale.

This study presents a comprehensive life cycle assessment of the Italian electricity mix, by employing primary data for the thermoelectric power generation and applying different allocation methods for the combined heat and power generation. In Italy’s electricity mix thermoelectric plants account for 51% of the total installed capacity, thus playing a crucial role within the Italian power generation system, despite the growing relevance of renewable energy sources. Emissions primary data have been extracted from the environmental statements related to the Italian power plants that hold an EcoManagement and Audit Scheme certification. Moreover, an exergy-based allocation method has been used along with an energy-based one, to enable an improved analysis of the thermal energy output from combined heat and power plants. The comparative analysis between the utilization of primary data and data from available database has revealed substantial disparities in terms of outcomes, thus shedding light on the relevance of the use of reliable primary data to achieve robust results. Furthermore, the exploitation of the allocation method used to deal with the multifunctionality of combined heat and power generation shows a substantial influence on the final impacts of the electricity mix.

Spent coffee grounds, SCG, are a waste product generated in significant quantities due to the large and widespread consumption of coffee worldwide. Current waste treatment options are not the best, as they do not consider the potential of SCG as a raw material for a variety of high-value products, from a bio-refinery perspective, while contributing to a more circular economy. In a biorefinery, several processes must be considered that need to be optimized, not only from an economic point of view, but also from an environmental point of view, such as ultrasound-assisted solvent (hexane) extraction process of oil from SCG biomass, which is the focus of this work. Hence, in this work, the carbon footprint of this process is analyzed based on a Design of Experiments results and following the Life Cycle Assessment methodology from a “cradle-to-gate” perspective. The functional unit is 1 g of extracted oil. The IPCC methodology implemented in RECIPE is used and the calculations were performed in the Simapro V8.5.2 software. The results show that it is the ratio of liquid (solvent) to solid (SCG) that most influences the carbon footprint of the extraction process.

The energy sector is a crucial industry that powers global economic growth, yet it is also among the least gender-diverse sectors, with women underrepresented at all levels, particularly in leadership positions. This gender gap not only limits women’s opportunities for career advancement but also hinders the sector’s potential for innovation and economic growth. This study proposes the application of an indicator inspired on the “benefit of the doubt approach” to assess the gender gap in the energy sector across European countries. The study considers four dimensions to assess gender parity in the energy sector, including employment and wages, senior management, entrepreneurship, and innovation. The findings indicate that countries with better gender balance have made strides in reducing the wage gap, although there are still gaps in other areas for both efficient and non-efficient countries, underscoring the need for further action. Despite their efforts in renewable energy, Germany, the Netherlands, Greece, and Italy have low rankings in gender balance, highlighting the persistent challenges these countries face in achieving gender equality in the energy sector. Conversely, Estonia, Slovenia, and Belgium are more often viewed as benchmarks of gender equality in the energy sector.

At present there are many didactic resources applicable to Engineering, both material (laboratory equipment) and virtual (videos, simulations). Often, however, these resources do not fit well into classroom teaching practice due to their orientation, length, or portability. This scarcity of didactic resources is more evident in the face of some teaching challenges such as the promotion of a research vocation, support in difficult content or help to overcome the gap between academic and professional perspectives. The search, selection or development of the most appropriate resources requires a strong dedication on the part of teachers. For this reason, the resources should be easily reusable in as many courses as possible. This communication describes the experience of a group of professors from the Area of Thermal Machines and Engines in the implementation of a hybrid bank of didactic resources oriented to the teaching of Energy and Sustainability Engineering. The process of bank design, application, and evaluation is illustrated using four of the resources produced: a demonstration of Nukiyama's experiment, a collection of heat transfer review videos, an introductory thermography hands-on session, and a class contest about fuel cell operation. The empirical findings suggest an enhancement in students’ academic performance, with mean grades increasing by 1.1/10–4.2/10, as well as in self-perceived learning. The suggested approach aims to improve students’ grasp of essential content, creating a more efficient and captivating learning environment.

Within the scope of sustainability and sustainable practices implementation, the Polytechnic Institute of Viana do Castelo (IPVC) is developing a pioneer project for phasing out the consumption of single-use plastic water bottles on campus premises and facilities, and consequently contribute to the compliance of the United Nations Sustainable Development Goals (SDGs). Under this scope, this article presents the design and implementation of the Refill_H2O Ecosystem in which a reusable water bottle interacts with an intelligent water dispensing station, enabled by the introduction of Internet of Things (IoT) Technologies on campus, to eliminate the use of single-use plastic water bottles in the premises of IPVC, a Portuguese Higher Education Institution (HEI), with nearly 6000 students. Three main contributions have been identified in this research: (1) by under-taking projects designed to foment innovation towards environmental issues, HEIs become a sustainability reference model to society as a whole; (2) a pilot that takes advantage of IoT technologies for broader interoperability and simple integration among the smart bottle (i.e., the interactive artifact), and the intelligent water dispensing station; and (3) the promotion of environmentally sustainable solutions designed to encourage practices that foment innovation, is the key to raise awareness of future generations concerning sustainability issues.

The European Union has been at the forefront of transitioning from a linear economic model to a circular economy, and understanding the Circular Material Use Rate is crucial in this context. The aim of this work is to contribute to a deeper comprehension of this indicator as a proxy for the Circular Economy, as defined by Eurostat, and to facilitate comparisons of how economies utilize circular materials. The study seeks to assess the behaviors of EU countries, develop future policies, and address barriers that prevent the efficient movement of materials within the countries under examination. To achieve these objectives, a linear regression analysis was conducted, examining the performance of the Circular Material Use Rate with respect to five independent variables: Resource Productivity, Recycling Rate, Environmental Tax Rate, Renewable Energy Rate, and Waste Generation. The results indicate that Resource Productivity and Recycling Rate have positive impacts on the Circular Material Use Rate, implying their significance in promoting circularity. Conversely, Waste Generation exhibited a negative impact, suggesting that reducing waste generation is crucial for enhancing circular material utilization. The European Union has demonstrated a strong commitment to optimizing production and consumption patterns, promoting the reuse of raw materials, extending their lifespan, and encouraging recycling practices. These findings contribute to the formulation of effective strategies and policies that can further propel the EU’s towards a more circular and sustainable economy.