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Building integrated photovoltaic systems are getting popular worldwide due to their building energy conservation properties alongside emission-free electricity generation capabilities. BIPV is a suitable way to generate renewable energy without wasting any land or building space. Bangladesh has set a target to generate a great portion of its electricity from solar energy and has already implemented different photovoltaic applications. However, Bangladesh still has no policy and guidelines to implement BIPV technology in its different types of buildings. In this study, we investigated the energy conservation potentials of three different configurations of semi-transparent CdTe combined building integrated window systems in an office building considering Bangladesh's climate conditions. To investigate the building energy conservation potentials of BIPV window systems, an EnergyPlus-based numerical simulation model was developed and validated with outdoor experiment data. The annual energy simulation results indicate that in all climate conditions, CdTe combined BIPV windows can save ranging from around 30–61% of electricity consumption compared to conventional window systems. Besides, it generate around 270 kWh electricity and ensure indoor daylight illuminance level at 300 lux. Moreover, in all climate conditions, south-faced BIPV windows are more efficient for power generation, but east-faced windows are more efficient to reduce net electricity consumption. [ABSTRACT FROM AUTHOR]

As countries implement renewable energy policies, it's important to understand the impacts of policies on sustainability. Population, economic and production changes affects in land use, water consumption and emissions along with trade-offs for limited resources to achieve food and energy security. Thailand faces increasing electricity imports and agricultural production, causing residue burning, a resource utilized for electricity generation. Thailand implemented a renewable energy policy and another to curb sugarcane residue burning addressing above challenges. The paper uses an extended input-output model in Thailand and the Northeast to understand impacts of these policies on output, labor income, employment, land and water use, etc. The study concludes these policies lead to supplementary increase in income, employment and value added contributing towards achieving SDGs through energy security, climate action, decent work and economic growth. At a national level, renewable energy policy is unable to capture a large potential of biomass electricity, while the no burn policy is better able to achieve sustainability through total output, income, employment, and water use. The renewable energy policy in Northeast Thailand is better able to capture the electricity potential. The Northeast also sees land use shifts from rice to cane, which could cause food security challenges. • Thailand faces growing challenges with energy security and crop residue burning. • To address the challenges, they implemented RE policies and crop burning policies. • The study uses extended input-output models in Thailand and Northeast Thailand. • We see positive effects of the policies on the economy, society and environment. • The policies fall short in capturing the full potential of biomass electricity. [ABSTRACT FROM AUTHOR]

The choice of a power plant in different nations depends on the required resources availability, abundance, and reliability. It is evident that renewable energy generation resources provide a more sustainable solution than the fossil fuels. However, as a complete system, renewable energy generation systems also have some overall environmental impacts on humankind and ecosystems. The main objective of this paper is to addresses the environmental effects caused by different types of renewable energy generation systems through process-based life-cycle impact analysis. A comparative study is carried out among different renewable energy generation technologies which include wind, photovoltaic, biomass, and hydro power. Life-cycle impact analysis has been carried out by Institute of Environmental Sciences (CML), Eco-indicator 99, Cumulative Energy Demand (CED) and Ecopoints 97 approaches. The superiority of this work is creating a comprehensive life-cycle inventory following a reliable global database, assessing the impacts for about 10 midpoint impact categories and three endpoint indicators, and taking account of the fossil-fuel-based energy consumption rate of each plant. The key findings reveal that photovoltaic power plants have the highest environmental impacts in the types of ozone layer depletion, fresh water aquatic ecotoxicity and marine aquatic ecotoxicity, while biomass plants impact on the categories of abiotic depletion, global warming, photochemical oxidation, acidification, and eutrophication. Moreover, the wind power plants have the more significant environmental effect on human toxicity and terrestrial ecotoxicity types. Overall, hydropower plants are found to be much more environment-friendly than other renewable electricity generation systems. [ABSTRACT FROM AUTHOR]

The aim of this study is to analyze the use of renewable energy resources in electricity generation and its impacts on greenhouse gas emissions mitigation in terms of emission intensity in Turkey. Thus, annual development of Turkey's electricity generation by renewable energy resources and its share in general total were examined. Annually, total greenhouse gas emissions from electricity production are determined and divided by total electricity production so that the emission intensity from electricity production is found in gCO 2 e/kWh. The effect of each source used in electricity generation on the emission intensity is demonstrated. Although there are volatilities in some years, it is revealed that the emission intensity, which was 563 gCO 2 e/kWh in 2008, decreased to 437 gCO 2 e/kWh in 2020 with an annual average decrease of 2.1%. These emission data belonging to Turkey are compared with the values of the European Union since it is a candidate country. As a result, it has been suggested that Turkey, which has a large renewable energy potential, should use this potential more effectively in order to further reduce its emissions from electricity generation. • Annual development of renewable energy in electricity generation were determined. • The impacts of renewable energy use on greenhouse gas emission were analyzed. • The emission intensity of electricity generation in Turkey was found as gCO2e/kWh. • The importance of renewable energy in mitigation of emission intensity is shown. • The use of nuclear energy is inevitable to reduce emission intensity. [ABSTRACT FROM AUTHOR]

Nowadays, photovoltaic (PV) system is one of the commonly adopted renewable energy systems. Many countries promote the application of PV system in buildings through green building certification schemes. On a building rooftop, there are various building facilities which may cast shadow on PV panels, resulting in reduction in electricity generation. Currently, there is rare attention to the neighbouring shading effect (NSE) on the performance of rooftop PV system. This study investigates the performance of PV system under NSE, using weather data of seven cities located at different geographical latitudes. These seven cities are Singapore (1.37° N), Hong Kong (22.3° N), Shanghai (31.17° N), Beijing (39.8° N), Harbin (45.72° N), Washington, USA (38.98° N) and London, UK (51.15° N). By comparing the building cases with and without considering NSE, the results unveil a substantial percentage difference in PV electricity generation and energy payback time (EPBT) ranging from −12.62% to −28.34% and −14.43% to −39.55%, respectively. Moreover, it reveals the dependence of percentage difference in PV electricity generation and EPBT on the latitude of a city. For the current green building certification schemes, mandatory requirement to take NSE into account for assessing the performance of rooftop PV system is recommended. • Rooftop of commercial building with surrounding facilities and building structure. • Shading effect on energy and environmental performance of rooftop PV panel system. • Values of percentage difference in PV energy generation range from 12.62% to 28.34%. • The corresponding range of values for energy payback time is −14.43% to −39.55%. • There is a dependence of the neighbouring shading effect on the latitude of a city. [ABSTRACT FROM AUTHOR]

Mining companies have increasingly shown interest in renewable electricity generation to address rising energy costs and reduce greenhouse gas emissions from their operations. Yet, the extent to which renewable energy sources are currently adopted by these companies is unknown. This work quantifies and characterises the current level of renewable energy adoption by Australian mining houses and the evolution of renewable energy technology adoption in this industry over time. Moreover, this work contributes to an increased understanding of factors driving or inhibiting the adoption of renewable energy in mining. In 2021, only 7% of the existing mines had or were planning to have a renewable energy system. Of the total renewable energy systems identified in this analysis, 15 were operational, 2 were under construction and 10 have been announced and planned for possible future deployment. The analysis of historical changes in renewable energy technology has highlighted that 70% of the existing operational systems have only been installed since 2019. The characteristics of the mines highly affect the decision to deploy renewable energy systems. 70% of the renewable energy systems analysed in this study were or are planned to be deployed on-site at off-grid mines powered by diesel and/or gas. Solar photovoltaic is the preferred renewable energy technology for mining operations, installed or proposed for 92% of the 27 projects included in this study. By providing a detailed picture of past and current trends of renewable energy adoption, this study identifies weaknesses and points of intervention in the emerging market for renewables in mining. In doing so, it offers guidance to policy and decision makers for the development of informed solutions to increase renewable energy uptake in mining. [Display omitted] • Renewable electricity evolution in Australian mining industry. • Mapping of operational and planned renewable energy systems across mines. • 7% of the Australian mines have an active or planned renewable energy system. • Solar PV is the most adopted renewable energy technology. • Renewable energy adoption mostly happens on-site at off-grid mines. [ABSTRACT FROM AUTHOR]

As the worldwide energy crisis worsens, renewable energy sources have undeniably opened new horizons for our society. It will offer an efficient solution to this severe energy crisis, environmental issues and fulfilling human energy needs. Therefore, six main criteria, social, economic, quality of energy, political, technical, environmental, and sixteen sub-criteria have been employed, and an assessment model is developed for prioritizing the most pertinent renewable energy sources for electricity generation in developing countries in which four major resources, solar energy, wind energy, hydropower, and biomass energy, are considered and their electricity generation potential. Furthermore, the integrated method with the analytical hierarchy process and VIekriterijumsko KOmpromisno Rangiranje are acquired for a comprehensive assessment. The results demonstrate that the economic criterion had the highest weight of (0.353) compared to the technical criterion, which took place second with a weight of (0.244) followed by environmental (0.205) and quality of energy with a weight (0.098), respectively. The political and social criteria have the lowest weights of (0.057) and (0.043). From the review, renewable resources seem to have sufficient potential to develop a sustainable electricity system. Likewise, the model priorities these resources, revealing that hydropower is the best renewable energy source option, followed by wind energy. Biomass energy and solar energy ranked third and fourth. The assessment performed in this study can help decision-makers in Pakistan to frame long-term energy policy directing for sustainability. • Integrated AHP-VIKOR with weighting method are used to prioritize the renewable energy sources. • Assessment of renewable energy resources is based on six criteria and sixteen subcriteria. • A criteria system is constructed (social, economic, technical, political, quality of energy and environmental aspects). • Economic and technical is determined as most essential criteria. • Hydropower is the best option for electricity generation, among the selected alternatives. [ABSTRACT FROM AUTHOR]

This research evaluates the South American Electric Energy System and its features related to the inclusion of renewable energies into the transition processes to leave fossil fuel-based energy systems behind. Analysis of the Ecuadorian case is a novel approach because in the first instance its matrix was based on the use of fossil fuels, with dire consequences of pollution, especially in the Amazon. Interest is growing in terms of economic, legal and social renewal, leaving behind the rapidly depleting oil systems which have been a polluting source. This research presents a novel analysis of the state of the Ecuadorian electricity system and after a flexible analysis in Energyplan, proposes the feasible renewable energy sources and their shares to guarantee the new demand in 2050 and an Ecuadorian 100% renewable electricity generation system, having a positive impact on the monetary, increasing production levels and improving the quality of life of its citizens. Installed power by 2050 is expected to be 20 GW and will require an annual production of 72.24 TWh. Hydro (6.02 GW), solar PV (5.7 GW) and wind (5.61 GW) will have the most impact on the Ecuadorian energy matrix. The average production cost of 1 MWh will be approximately 18 US cents. [Display omitted] [ABSTRACT FROM AUTHOR]

Renewable energy technologies (RETs), particularly solar and wind energy technologies, have experienced a rapid decline in their costs over the last two decades. Several studies claim that RETs are cost-competitive with fossil fuel technologies based on their levelized costs of electricity (LCOE), the most common indicator used to compare the cost competitiveness of electricity-generating technologies. However, no consensus exists due to the wide variations in factors influencing the LCOEs across countries and technologies. This study calculates more than 4000 LCOEs for 11 technologies, varying all input variables. It shows that the LCOEs for RETs, except concentrated solar and offshore wind, are lower than those for fossil fuel technologies at the lower range of capital costs and discount rates of 10% or lower. However, for a reasonable range of input variables, the study cannot justify the low auction prices for solar power, below US$20/MWh, recently observed in some parts of the world. The study illustrates how various factors influence the cost of electricity generation across technologies. It also compares the trends in electricity generation costs between RETs and fossil fuels over the last two decades. [ABSTRACT FROM AUTHOR]

Despite the importance of cost of capital and expected returns from investing on renewable electricity generation in Africa on one hand and the implications of such investments on economic, social and environmental factors on the other. These concepts are not well understood by non-finance and finance actors respectively. Studies that analyze renewable energy-growth nexus at regional and global level are lacking. Instead, existing studies emphasize on individual countries or panel of countries. The paper undertakes comparisons of costs and returns of selected renewable energy technologies in Africa and presents estimates of its impact on Africa's economic growth between 1990 and 2014. Even with abundant renewable resources and well performing technologies measured using levelized cost of electricity and expected internal rate of return, investment on renewable electricity generation is quite low. Findings from Autoregressive Distributed Lag approach and cointegration established a long run relationship among hydro power generation, carbon emissions and electricity consumption. Error Correction Model results suggest that investment in renewable generations excluding hydro power generation is boosted by economic growth, so long as development of such renewables corresponds with lesser carbon emissions. To accelerate renewable development, SSA countries will need to deploy initiatives that enhances national economic growth. [ABSTRACT FROM AUTHOR]

The challenge of global warming requires deep decarbonization of the electricity system, which can be achieved with a higher share of renewables in the electricity mix. However, the driving mechanism for renewable penetration in electricity production has not been clearly revealed so far. Using the data of the European Union (EU) during 2001–2017, this paper aims to investigate the spatial-temporal heterogeneity and dynamic evolution mechanism of renewable electricity penetration. To this end, from the investment-production-consumption perspective, renewable electricity generation is decomposed into seven factors through temporal and spatial factor decomposition methods. Then, this paper integrates the factor decomposition results into a coupling elasticity analysis to study the dynamic evolution mechanism of renewable penetration in electricity production. The results are as follows. (1) Investment structure contributes the most to increasing renewable electricity generation, while the energy intensity effect and renewable generation-to-capacity ratio effect are the main reasons for the reduction in renewable electricity generation. The effect of technological structure is minor. (2) The economic scale effect and the investment structure effect are dominating factors accounting for the regional difference of renewable power generation between the EU countries and the benchmark region. (3) The progress of renewable electricity penetration accelerates over time for the EU, western EU, and eastern EU. The Western EU has realized remarkable progress in facilitating renewable electricity penetration during 2009–2017. (4) On the whole, the investment effect makes the largest contribution to promoting renewable electricity penetration, while the production effect is the major inhibiting factor, showing that there is considerable potential in renewable generation efficiency improvement in the EU. This paper provides insightful implications for energy policies aimed at the shift towards a low-carbon electricity system in the EU, which also gives a reference for other economies. [ABSTRACT FROM AUTHOR]

Brazilian charcoal is produced from planted eucalyptus forest wood in traditional batch reactors. The ordinary technology applied in Brazil does not use pyrolysis waste gases, which leads to the loss of 30% of wood energy and decreases air quality. This study evaluated the synchronous use of industrial batch kilns, waste gas burning, and energy recovery to produce electricity. Three scenarios were analyzed: (S1) Eucalyptus charcoal production without gas burning (Base Scenario); (S2) with gas burning; and (S3) with gas burning and electricity generation. Since a eucalyptus forest can fix carbon into its biomass through photosynthesis and finally into charcoal, S1 was able to reduce 3402.5 kg of CO2-eq per Mg of charcoal produced, and S2 reduced 6453.1 kg of CO2-eq due to waste gas methane burning. Electricity production is environmentally positive for all evaluated environmental indicators thanks to gas pollutants destruction and renewable energy generation. For S1, a ratio difference of 6.3 was found between the output of renewable energy and fossil energy input during the charcoal life cycle. For a combined production of charcoal and electricity (S3), a ratio difference of 6.9 was found. Photochemical oxidation was the main impact which can be significantly reduced by adopting gas flaring. • LCA results of batch carbonization reactors working in synchrony with waste gas energy recovery are discussed. • Electricity production can significantly reduce charcoal life cycle impacts in all LCA evaluated categories. • Energy recovery has shown a very high life cycle energy output/input relation of 6.9 yr-1. • Methane burning and electricity generation reduced 3050,6 kg of CO2eq. per Mg of produced charcoal. • The main impact category is Photochemical Oxidation which can be 90% reduced by gas flaring. [ABSTRACT FROM AUTHOR]

Globally, demand for electricity has seen a steady increase, with nations striving to meet the demand. However, Nigeria is abysmally struggling to meet the increasing demand with the meagre per capita electricity consumption of 151 kWh, which is lower than the average of per capita electricity in Africa. Presently, the grid-tied electricity installed capacity in Nigeria, estimated at 13,435 MW is primarily generated by fossil and hydro-power plants at approximate distribution of 82.3% and 17.7%, respectively. This work presents single capsule that shows a holistic narrative of the energy access sector in view of energy penetration, sustainability, technology advancement and energy policy evolution. From available records, renewable energy sources in Nigeria are equitably distributed throughout the country, unlike the fossil reserves that are mostly concentrated in the south-south geopolitical zone. Also, there are huge potentials buried within untapped renewable energy in the country, namely wind, small-scale hydropower, geothermal, tidal and biomass energy. Furthermore, cutting edge power generation technologies that incorporate fuel cell, gas-, steam-, and low grade-turbine with carbon capture and fired by dual fuel of natural gas and biomass is promising for both energy access and climate action. The Federal Government of Nigeria's friendly energy policies, coupled with political will to excite implementation are panacea to significantly drive energy access for sustainable socio-economic development. [Display omitted] •The current electricity generation in Nigeria is relatively poor, and below policy targets. •Electricity generation in Nigeria is heavily dominated by high-carbon emission technologies. •Nigeria has huge renewable energy potentials to meet the Sustainable Development Goals SDG-7 and SDG-13. •Natural gas-biomass (gasified) fuelled low-carbon energy conversion technology with CCS is promising in Nigeria. [ABSTRACT FROM AUTHOR]

Promotion of solar energy as a new promising renewable energy source for Smart City projects in Thailand plays an important role in driving the economy, society and the environment. A novel conceptual framework with different solar radiation indexes was developed to investigate and evaluate the efficiency of photovoltaic (PV) energy production by comparing predicted and actual results for energy acquired from the reference project. The trend of potential energy production was predicted from solar radiation data as the basis for further calculations to evaluate PV system efficiency through a techno-economic analysis of project development. A mathematical model was developed to predict the obtained electrical energy by considering the suitable location-specific solar radiation indexes including direct normal radiation, All-Sky insolation incident on a horizontal surface, direct normal irradiation and global horizontal irradiance. The developed model was tested with three existing Smart City projects at various locations in Thailand. The All-Sky index was determined as the most suitable option to evaluate new PV development projects. Highest energy production from the PV projects occurred in March and April. Energy production efficiencies of the PV systems were estimated in the range of 3.97–4.32 kWh/kW p. The techno-economic analysis suggested that the PV project had an internal rate of return of 14.30–15.75% and payback period of 6.18–6.74 years. The proposed conceptual framework was a promising tool for decision-making regarding Smart City PV projects. • The solar energy is promoted as a promising renewable energy for Smart City projects in Thailand. • The location-specific solar radiation index was incorporated in the energy prediction model. • All-Sky Index was found to be the most suitable index to evaluate the power generation potential. • Energy production efficiencies of Smart City's PV projects were in the range of 3.97–4.32 kWh/kWp. • Techno-economic analysis suggested that PV project had internal rate of return of 14.30–15.75%. [ABSTRACT FROM AUTHOR]

This research presents a scenario for a 100% renewable energy system for the City of Cuenca, Ecuador, with a projection to the year 2050. The transition process starts with Ecuador's change in the productive matrix with reforms from the legal and business strategies point of view to the year 2050. Advances in energy material are dependent on political uncertainty both at the country (Ecuador) and local (Cuenca) levels. It is possible to stop using fossil fuels due to the implementation of new renewable energy sources, potentially rich in the Ecuadorian Southwest and evidenced in the National Plan for a Lifetime. Currently, there is evidence of accelerated changes concerning legal regulations, including the construction of several electric power generation plants. This change in the national productive matrix implies, among others, the implementation of electric vehicles and the change of natural gas stoves for electric ones, and the implementation of the "4 Rios" tram that crosses the city from North-South and South-North, incorporating 100% renewable energy generation, which would provide heat in urban and marginal urban areas. All the systems created in Ecuador, such as heating, cooling, transportation, security etc., will allow an increasing penetration of renewable energy until it reaches 100%. [Display omitted] • The scenario is 100% renewable energy by 2050 in the City of Cuenca in Ecuador. • The surrounding of the city of Cuenca have great renewable energy potential. • A more environmentally friendly approach is proposed. • Reference horizon achievable by 2050 based on its energy wealth. • Harmonious development of the city of Cuenca inserted in the Ecuadorian context. [ABSTRACT FROM AUTHOR]

At present, energy represents a key element in the social and economic development of a territory. This is particularly true for fragile territories that are not interconnected, such as small island states. As is true for many of the Small Island Developing States (SIDS) worldwide, the energy situation of the Comoros is substantially based on fossil fuel imports. The socioeconomic development of this archipelago is overwhelmingly dependent on energy security from sustainability, availability and affordability perspectives. As a forward-looking response to energy vulnerability, the deployment of renewables to diversify the generation of electricity appears to be an essential prerequisite for guaranteeing a sustainable future. Nevertheless, despite a high potential for renewable energy, only 3.8% of the electricity supply in the Comoros is provided by hydropower. This paper provides a comprehensive overview of the energy situation throughout the Comoros and focuses on renewable energy opportunities to facilitate the supply of green power. This study ultimately shows that renewable energies are rarely exploited despite the powerful potential of different resources. Finally, this paper attempts to provide recommendations for the Comoros to pursue a more sustainable future. • Analysis of the current energy situation of Comoros. • Defining renewable potential and ongoing actions. • Analysis of the specific barriers and policy to the development of RES in the Comoros. [ABSTRACT FROM AUTHOR]

The increased competitive power of electricity generation from renewable energy sources (RES) against fossil fuels has aroused debates on the fiscal burden that policy-based subsidies put on the public funds. During this period, market-based mechanisms, the auction mechanism in particular, have become increasingly popular. Success of an auction mechanism depends to a large extent on how well design choices are adapted to the specific context of a country. Drawing on stakeholder views on Renewable Energy Source Zones (YEKA) auctions, this article aims to evaluate the auctions mechanisms and propose policy recommendations for enhancing their efficiency and effectiveness. Research findings show that despite the continuing relevance of the feed-in-tariff (FiT) mechanism for the development of the RES sector, today financing costs of renewable energy projects are high and market predictability is low. The FiT mechanism should be retained after the policy change concerning the tariffs, which is expected to take place in 2020, and the future auctions should be smaller in volume and be distributed across different geographical regions. Although large-volume auctions are organised in Turkey, satisfactory conditions for competition have came into being and prices lower than FiTs were formed. • Unpredictability is seen as a barrier in development of the renewable capacity. • Prices resulting from auctions turned out to be lower than Feed-in-Tariffs. • Auctions should be accompanied by other policy mechanisms. • The new auctions should be of smaller volume and geographically distributed. • Auctions should be organised at regular intervals and a pre-determined schedule. [ABSTRACT FROM AUTHOR]

The global energy demand has increased interest in the development of new technologies that offer alternative, cost-effective energy solutions with minimal environmental impact. Among these technologies, is microbial fuel cell (MFC), which takes advantage of the electrical energy produced through the metabolic reactions of microorganisms when they encounter a substrate. This study assesses the electric power generation potential of MFC configured using as a substrate and source comprising a mixture of soil, sand, organic fertilizer, and ash in a proportion of 3:2:1:1/2. Native plants (Torenia fournieri , Kalanchoe blossfeldiana , Pentas lanceolata , Nephrolepis exaltata , Begonia semperflorens , or Asplenium nidus) were planted to promote the exchange of organic chemical species and nutrients for renewable electrical energy generation. The configuration, constituting a system of fuel cells with microorganisms and plants (Plant Microbial Fuel Cell, PMFC), demonstrated varying whose efficiency levels, determined by measuring the potential between the cell electrodes. The highest voltage obtained in the PMFCs was 0.609 V for the Begonia semperflorens plan, while the lowest was 0.069 V for Asplenium nidus. Torenia fournieri and Asplenium nidus presented the highest voltage peaks at 1.782 and 1.587 V, respectively. Of the plants studied, Nephrolepis exaltata and Asplenium nidus were the only surviving plants after the measurements. When all were connected in series, excluding Asplenium nidus due to its instability, it resulted in an average voltage of 1.856 V. The minimum recorded voltage was 1.540 V, and the maximum electrical potential reached 2.050 V. Analysis of the soil samples, along with the substrate before and after the experiment, identified six electrogenic bacteria: Escherichia coli , Pseudomonas sp., Erwinia sp., Lactobacillus sp., Enterococcus sp., and Clostridium sp. The Escherichia coli was only present in the soil and substrate sample before the experiment, while the concentration of Pseudomonas sp. and Erwinia sp. , increased. This study confirmed that PMFCs with low-cost substrates and native Caribbean plants, represent a promising technology that could drive energy development in developing countries, especially in remote areas lacking access to electricity. This implementation of PMFCs aligns with sustainable energy practices, offering a cost-effective strategy, that can be replicated globally, contributing to the achievement of Sustainable Development Goal 7: Ensure access to affordable, reliable, sustainable, and modern energy for all. [Display omitted] [ABSTRACT FROM AUTHOR]

The present article sets out to examine the connection between energy transition and factors associated with renewable energy sources, buildings and other sectors, placing emphasis on France. The methodology includes: Collection of scholarly writings, classification, identification of research questions, bibliographic analysis, identification of important findings, discussion. The results of a study (EDF, Le nucléaire en chiffres) demonstrated that, in 2019, around 80% of the electricity production from nuclear energy (in France) was provided by 4 regions: Auvergne-Rhône-Alpes , Grand Est , Centre-Val de Loire , Normandie. France has a high dependence on nuclear power generation and, for this reason, renewable-energy penetration is an imperative part of the French energy transition. Numerous studies show that energy transition requires actions based on burgeoning and avant-garde technologies, and effective policies. Moreover, energy transition poses challenges: decisions on nuclear power plants, sustainable development of small-island economies, etc. A discussion on the energy transition in Corsica (France) is also provided. Regarding the French overseas territories Corse (Corsica), Guadeloupe , Martinique , Guyane , Mayotte , Réunion , the findings of a study (Rakotoson and Praene, 2017) demonstrate that thanks to renewable energy sources/network interconnection, Corsica and French Guiana have lower emissions in comparison to the other territories: 0.505 and 0.373 kg CO 2.eq /kWh e , respectively. • The role of renewable energy sources in energy transition has been analysed. • Factors related to buildings, industry, etc. have been discussed (emphasis: France). • France, 2019.→ ≈ 80 % of the nuclear electricity generation was provided by 4 regions • There are challenges such as energy storage and decisions on nuclear plants. • Corsica and French Guiana: emissions 0.505 and 0.373 kg CO 2.eq /kWh e , respectively. [ABSTRACT FROM AUTHOR]

Pakistan is facing severe electricity crisis due to lack of investment in power sector, depleting gas resources and dependency on imported oil. Utilization of indigenous and renewable energy resources is the best way to compensate energy need and reduce fossil consumption. Being an agrarian country, huge amount of agricultural residue is generated each year, which can be used as a cheap input to generate electricity. Aim of this research is to assess the total potential of electricity that can be generated from Agricultural Residue (AR) in Pakistan. The paper focuses on district-wise resource assessment for electricity generation in the province of Punjab. Estimated 60 Mega Tonne (Mt) of AR is generated in Punjab every year from 5 major crops (wheat, sugarcane, rice, maize, and cotton). AR is used for various purposes but still large amount of residue is left unused and burnt openly in the fields. As a methodology, certain factors are used to calculate the Net Available Residue (NAR). This research shows that a lot of potential is available in Pakistan to generate electricity form biomass, in total around 1700 MW electricity can be generated from agricultural residues of 4 main crops (Maize, Cotton, Wheat and Rice). It is also found that maize stalk producing districts of central Punjab are the best location for installing BPP and also it is cheapest to produce electricity from maize stalk with LCOE of 6.8 cents/kWh. • The assessment of the power generation from Agricultural Residue (AR) in Punjab, Pakistan is performed. • District-wise resource assessment for electricity generation is done in the province of Punjab. • Estimated 60 Mega Tonne of AR is generated in Punjab every year from 5 major crops. • In total around 1700 MW electricity can be generated from agricultural residues of 4 main crops. • Maize stalk producing districts of central Punjab are the best location for installing BPP. [ABSTRACT FROM AUTHOR]

Short-term forecasting of electricity generation from variable renewable energy sources is not an end in itself but should provide some net benefit to its user. In the case of electricity trading, which is in the focus of this paper, the benefit can be quantified in terms of an improved economic outcome. Although some effort has been made to evaluate and to improve the profitability of electricity forecasts, the understanding of the underlying effects has remained incomplete so far. In this paper, we develop a more comprehensive theoretical framework of the connection between the statistical and the economic properties of day-ahead electricity forecasts. We find that, apart from the accuracy and the bias, which have already been extensively researched, the correlation between the forecast errors and the market price spread determines the economic implications - a phenomenon which we refer to as 'correlation effect'. Our analysis is completed by a case study on solar electricity forecasting in Germany which illustrates the relevance and the limits of both our theoretical framework and the correlation effect. • The economics of short-term electricity forecasts are studied analytically and empirically. • The value and the risk of forecast-based electricity trading are evaluated. • We find that the economics depend on the correlation of forecast errors with prices. • Hence, the most accurate forecast is not necessarily the most accurate. [ABSTRACT FROM AUTHOR]

This paper deals with the environmental assessment of two electricity scenarios in Sicily, for 2030, characterized by a high exploitation of renewable energy sources in order to quantify the potential contribution of the local strategies in the achievement of the European climate policies and the potential improvement in the future electricity mix, compared to the current one (2014). In order to match these goals, authors integrate the Life Cycle Assessment with a scenario analysis. The future electricity mix scenarios, characterized by a share of renewables (57% for 2030-BS scenario and 51% for 2030-DS scenario) show a reduction of the greenhouse gases emissions per kWh of electricity generated, compared to the current one in which renewables account for 24%. Greenhouse gases emissions decrease by 39.9% in 2030-BS and by 32.9% in 2030-DS. However, the analysis highlights that the state of development of technologies does not allow improvements in a whole set of impacts categories. Particularly, freshwater ecotoxicity increases by around 30% and resources depletion by more than 100%. Results of this study can be used by local authorities as knowledge base in the definition and "ex-ante" evaluation of site-specific low-carbon energy strategies in Sicily. • The scenario analysis integrated with the LCA methodology was presented. • Electricity generation scenarios in 2030 in the Italian context was build. • Marginal electricity generation technologies were identified based on site-specific data. • A high penetration of renewables in the electricity generation mix allows decreasing a wide range of environmental impacts; Improving renewable technologies is paramount for better resource efficiency A high penetration of renewables in the electricity generation mix allows decreasing a wide range of environmental impacts; Improving renewable technologies is paramount for better resource efficiency and toxicity control. [ABSTRACT FROM AUTHOR]

The penetration of renewable energy sources for electricity generation is critical to decarbonize electricity systems, a main goal in the context of the energy transition. Among renewable energies capacity additions, wind energy has played a dominant role in the European Union and elsewhere, fuelled by technology cost reductions and public promotion schemes. In turn, wind deployment has led to considerable socioeconomic and environmental benefits in terms of CO 2 emissions reductions, avoidance of fossil fuels and employment creation. The aim of this paper is to assess those socioeconomic and environmental benefits of wind energy deployment in the European Union and their evolution over time. Based on two novel methodologies, which allow a disaggregated analysis per country and stage of the supply chain (only for employment creation), an ex-post calculation of those benefits over the 2008–2016 period has been carried out. Our results show that, overall, those benefits are considerable and have increased over time. However, some benefits are more relevant than others. In fact, the monetary calculation of the fossil fuel savings is twice the benefits in terms of CO 2 emissions abatement. Their relevance also differs across countries and, for employment creation, across distinct stages of the value chain. • Ex-post calculation of the benefits of wind energy in the EU in the period 2008–2016. • Assessment of the emission reductions, avoidance of fossil fuels and employment creation. • The monetary quantification of the fossil fuel savings is twice the benefits of CO 2 emissions abatement. • More than 2.5 million jobs created in the period 2008–2016 in the EU28. • Policy costs are higher than benefits from CO 2 and fossil fuel reductions. [ABSTRACT FROM AUTHOR]

The amount of electricity generation and its availability to the residents of a country reflects its level of development and economic condition. Water being one of the cheapest and renewable sources of energy, is being used to produce one-quarter of the total electricity production in Pakistan. This article presents a forecasting study of hydroelectricity consumption in Pakistan based on the historical data of past 53 years using Auto-Regressive Integrated Moving-Average (ARIMA) modeling. Based on the developed forecasting equation, the hydroelectricity consumption was predicted up to the year 2030. For validating the reliability of the forecasted data, the results were compared to the actual values which showed good fit with minimum deviation. The forecasted values of hydroelectricity consumption revealed an average annual increment of 1.65% with a cumulative increase of 23.4% up to the year 2030. The results were compared with the hydroelectricity generation plans of the Government of Pakistan for its effectiveness. A sensitivity analysis was also performed to study the relation of hydroelectricity consumption to the annual population and GDP growth rate of the country. The research shall significantly prove to be useful in better planning and management of water resources of Pakistan for future. • ARIMA modeling is performed to forecast hydroelectricity consumption for Pakistan. • Forecasting equation is validated and proves to be reliable for use. • Results show an increase of 23.4% in hydroelectricity consumption up to year 2030. • A sensitivity analysis for annual GDP and population growth rates is presented. • Results are also compared with planned hydroelectricity generation up to year 2030. [ABSTRACT FROM AUTHOR]

Since the electric grid does not store electrical energy, the demand for electric power must be matched by the production almost instantaneously. The supply-demand balance imposes a severe constraint on the penetration of renewable energy sources – especially wind and solar – in the power production markets of all nations, because solar irradiance and wind energy are not available at all hours of the day and exhibit daily and seasonal variabilities. Using the hourly data of the electric power demand in the Electric Reliability Council of Texas, we calculate the implications of this constraint on the substitution of fossil fuel power plants with renewable energy sources. When the market penetration of renewables increases and the utilization of solar and wind energy sources expands to approximately 25%–30% of the annual electricity production, significant energy storage capacity is needed. Simulations of the entire electric grid are performed to determine the power ratings of the renewable sources and the necessary storage capacity to substitute part or all of the fossil fuel power capacity in Texas with renewable energy sources. • The production of electricity from renewables does not match the demand. • At renewable penetrations greater than 25–30% energy storage is necessary. • Energy storage becomes a limitation to the further development of renewables. • Less storage is needed for the substitution of coal with wind and solar energy. • Significant storage is required for the substitution of all fossil fuel plants. [ABSTRACT FROM AUTHOR]

Hot dry rock (HDR), as a clean renewable energy source, can help fulfill future energy needs and reduce the greenhouse effect. This energy source in the Qiabuqia geothermal field of Northwest China is expected to generate electricity. In this study, we used the lab parameters and the GR1 well data from the Qiabuqia site to numerically investigate the reservoir stimulation and electricity generation from a three-horizontal-well EGS system created in the granitic reservoir at depth 3500–3700 m, and at an average temperature of 218 °C. Slickwater fracturing and the resulting reservoir scenarios for different expected conditions in the region were analyzed in order to find suitable fracturing strategies. We then proposed three optimized EGS scenarios and evaluated their economic and environmental benefits. Results indicate that EGS power generation significantly depends on the reservoir stimulation results. The potential 2.61–4.90 MW installed capacity and 433.72–913.05 GWh total power generation are expected to be realized if the well spacing of 300–500 m and the hot water circulation rate of 20–40 kg/s in a 20-year period are achieved via the slickwater fracturing treatment. The final production temperature can be maintained at approximately 200 °C, and the corresponding temperature drops less than 10%. Such a case of geothermal engineering is expected to result in a reduction in greenhouse gas (GHG) emissions of 0.15–1.1 Mt, and its levelized cost of energy (LCOE) is estimated at 0.047–0.066 $/kWh. Image 10670 • Enhanced geothermal systems under various reservoir scenarios are investigated. • Reservoir stimulation and hydrothermal simulation approaches are integrated. • Optimized three-horizontal-well EGS systems based on slickwater fracturing treatments are proposed. • The economic and environmental benefits of the power generation by the EGS system are technically evaluated. [ABSTRACT FROM AUTHOR]

Fossil fuels are the major source of electric power production in Alberta, Canada (about 90%). This makes electricity generation sector of Alberta an intensive source of CO 2 emissions and a good candidate for greenhouse gas (GHG) emission reduction by replacing fossil fuels with low-carbon renewable energy sources. Wind and geothermal energy are two low-carbon energy sources that can be considered for electricity generation in Alberta. However, the relatively high cost of geothermal energy and intermittent nature of wind energy hinder their widespread use in the province. To address these challenges, in this study we develop a model to simulate the performance of conventional geothermal and Compressed Air Energy System (CAES)-geothermal power plants with or without wind energy in a typical hot dry rock (HDR) reservoir using CMG STARS, and Visual Basic Applications (VBA) platform in Excel. Our findings show that wind/CAES-geothermal scenario with McIntosh technology has the lowest LCOE (7.8–11.8 ¢/ kWh) with the emission intensity of 88–126 gCO 2 / kWh. Furthermore, this scenario could reach the 10% IRR value, which results in total GDP impacts of $1,020 to $1,386 million and creation of 4,489 to 6,842 jobs in Alberta and Canada over a 10-year period. • Hybridizing wind and geothermal energy using CAES with LCOE of 7.8–11.8 ¢/kWh. • Identifying the best location for wind and geothermal energies across Alberta. • Re-using the inactive wells in Alberta for further LCOE reduction. • Estimating the economic impacts of a wind/CAES-geothermal plant. [ABSTRACT FROM AUTHOR]

Human activities imply a high and increasing consumption of electricity. In this context, renewable sources, such as solar and wind energy, stand out due to the ecological and economic advantages associated with their use, but bring with them the need for monitoring and analyzing climatic variables such as solar irradiation and wind speed, in order to determine the potential of solar, wind or hybrid (solar and wind) generation of a region. The main objective of the present study was to develop a method to rank the top locations or regions for wind, solar and hybrid electricity generation potential. In addition, two databases were created using spatial interpolation techniques to define values related to solar and wind energy sources in a case study for the state of Paraíba, Northeast Brazil. Thus, using public data from ground stations and satellites, two interpolation procedures were evaluated, Inverse Distance Weighted (IDW) and Kriging. Next, the best evaluated method (Kriging) was used to develop a database with exclusive resolution of 0.05° (latitude and longitude) for analysis of the wind, solar and hybrid potential of the Paraíba state, Brazil, used as case study. Finally, an index was created to determine the municipalities in the state that stand out with the best indicators for hybrid generation. From the index created, it was observed that the municipalities belonging to the intermediate geographical regions of Sousa-Cajazeiras and Patos have the best indicators for solar generation, while the regions of Campina Grande and João Pessoa stand out with greatest potential for wind energy production. The region of Campina Grande also had the best results for hybrid generation potential. The IP-PB index was the main contribution of this work, since the method can be applied to different regions of the world for the same purpose and other indexes for estimating renewable production potential were not found in the literature. [ABSTRACT FROM AUTHOR]

Building-integrated photovoltaics (BIPV) can produce power while occupying little urban space. Photovoltaic-integrated shading devices (PVSDs) are a key component of BIPV that can generate electricity while blocking excess daylight. However, previous studies have lacked a systematic design of PVSDs that accurately estimates the trade-offs between indoor sunshade duration and electricity generation. This study proposes a multi-objective optimization framework for maximizing PV potential, minimizing PV area, and enabling proper sunshade duration in complex urban surfaces. A GIS-based spatiotemporal analysis and optimization approach was applied to three PVSD planning scenarios: (i) parallel to the horizontal land surface, (ii) inclined at an angle equal to the local latitude, and (iii) rotated in real-time to keep the PV surface perpendicular to the solar radiation. Different PV widths are determined under different scenarios considering power generation and solar shading duration. In the real-time rotating scenario, the optimized 0.7-m-wide PVSDs can generate 0.861 GWh of electricity annually, with a competitive average power generation efficiency of 0.811 kWh/m2/day and a solar shading duration of 6.61 h/day. Flexible installation scenarios are suggested to account for shading from other upper PVSDs and surrounding buildings. This study can facilitate solar farming in global cities and contribute to renewable energy penetration. [ABSTRACT FROM AUTHOR]

Abstract Growing pace of urban living is expected to simultaneously aggravate both the waste and the energy crises. This study presents feasibility assessment of a community scale hybrid renewable energy system (HRES) utilising biomass to serve the local energy needs while reducing the household solid waste volume. A modelling framework is presented and evaluated for a biomass HRES, comprising of a Wind turbine-PV Array-Biogas generator-Battery system, applied to two European cities - Gateshead (UK) and Sofia (Bulgaria) - accounting for their distinct domestic biowaste profiles, renewable resources and energy practices. Biogas generator is found to make the most substantial share of electricity generation (up to 60–65% of total), hence offering a stable community-scale basal electricity generation potential, alongside reduction in disposal costs of local solid waste. Net present cost for the biomass-integrated HRESs is found within 5% of each other, despite significant differences in the availability of solar and wind resources at the two sites. Based on a survey questionnaire targeting construction companies and energy solution developers, project costs and planning regulatory red tapes were identified as the two common implementation challenges in both the countries, with lack of awareness of HRES as a further limitation in Bulgaria, impeding wider uptake of this initiative. Graphical abstract Image 10110 Highlights • Integrating biomass overcomes local municipal solid waste (MSW) disposal issue. • Moderate community loads can be met economically using a biomass generator. • One tonne MSW can potentially produce up to 1000 kWh of electricity. • Project net present cost strongly depends on the size of the biomass generator. • Project costs and legislative red tapes deter localised waste-to-energy initiatives. [ABSTRACT FROM AUTHOR]

Abstract Solar energy is one of the important energy sources and countries have realized the important role of renewable energies due to the depletion of conventional energy sources. In this study, a GIS-based analysis is utilized for investigating the feasibility of solar energy in Iran. To evaluate the concept of risk into the GIS-based analysis for determining optimal areas for installation of solar power plants an Ordered Weighted Averaging (OWA) approach is used for the first time. Integration of OWA-based approach and GIS analysis provide models that determine the priority of regions from risk-free decision to risky decision strategies. The results show that Kerman, Yazd, Fars, Khuzestan, Sistan and Baluchistan, South Khorasan and Isfahan provinces have a good capacity to invest in solar energy projects. The GIS-based analysis indicates that the values of installed solar power plants percentages in high chosen areas for the most pessimistic and optimistic strategies are 7% and 64%, respectively. Highlights • A new model is used to evaluate the solar energy in Iran. • To evaluate solar energy potential a risk analysis is added to GIS-based method. • An Order Weight Averaging is utilized for first time in solar energy assessment. • A location analysis is done for currently working solar plants. • A maximum of 498 W/m2 solar radiation is achievable yearly. [ABSTRACT FROM AUTHOR]

Abstract The present work aims to present the electrical energy situation of several French islands spread over the World. Various aspects are successively studied: repartition of energy means, renewable energy part in the production with a focus on the intermittent renewable sources, legal and financial aspect. The electrical situation of the islands is compared with the French mainland one. The electricity production cost in the islands are presented and the financial features for renewable energy in France are exposed. In a second part, a focus is realized on the Corsica Island situated in the Mediterranean Sea and partially connected to Italy. Successively, the energy mix, the objective of the new energy plan for 2023 and the renewable energy situation, present and future, are presented. Even if the integration of non-programmable renewable energy plants is more complex in small insular networks, the high cost of electricity generation in such territories encourages the introduction of wind and PV systems. The islands are good laboratories for the development of intermittent and stochastic renewable energy systems. Highlights • Several case studies for French islands spread over the planet. • Electrical particularities of the not-interconnected territories and recognition of these specificities by the law. • Particular situation of Corsican Island. • Integration of intermittent renewable sources in small electrical networks. [ABSTRACT FROM AUTHOR]

Abstract Renewable energy is expected to constitute a significant proportion of electricity production. Further, the global population is increasingly concentrated in cities. We investigate whether it is possible to cost-effectively employ 100% renewable energy sources (RES)—including battery energy storage systems (BESS)—for producing electricity to meet cities' loads. We further analyze the potential to use only RES to meet partial loads, e.g., by meeting load demands only for certain fractions of the time. We present a novel flexible-load methodology and investigate the cost reduction achieved by shifting fractions of load across time. We use it to evaluate the impacts of exploiting flexibility on making a 100% RES scenario cost effective. For instance, in a case study for Kortrijk, a typical Belgian city with around 75,000 inhabitants, we find that from a purely economic viewpoint, RES–BESS systems are not cost effective even with flexible loads: RES–BESS system costs must decrease to around 40% and 7% (around 0.044 €/kWh and 0.038 €/kWh), respectively, of the reference levelized costs of electricity to cost-effectively supply the city's load demand. These results suggest that electricity alone may not lead to high RES penetration, and integration between electricity, heat, transport, and other sectors is crucial. Highlights • Analysis of potential of 100% renewable energy to meet a city's electric loads. • Model to analyze the cost-effectiveness of meeting a city's partial electric loads. • Model to analyze the cost-effective exploitation of flexibility to meet city loads. • Renewable is costlier than non-renewable electricity even with flexible load shifts. • Combining electricity, heat, transport, etc., is key for high renewables penetration. [ABSTRACT FROM AUTHOR]

Abstract Flexible power provision from biogas can significantly contribute to energy systems with high shares of renewables. However, the characteristics and demands for this flexibility are not clearly defined or measured. In this paper eight indicators are defined to shape "flexibility" and perform a downstream investigation of eight research projects focusing on flexible energy provision of biogas plants. The indicators are structured in three dimensions (1) velocity (ramps) by which the system can be modulated, (2) power range (bandwidth) and (3) duration for specific load conditions. Based on these indicators bottlenecks for the flexibility potential were identified. One crucial result shows that short-term flexibility of biogas plants is mainly driven by properties of the combined heat and power unit (velocity and bandwidth). The long-term flexibility depends mainly on gas storage, mode of operation and ability for modulation of the target gas production. Highlights • Development of eight indicators to measure flexibility performance of biogas plants. • Application of flexibility indicators to nine research projects. • Sensitivity analysis for flexibility indicators based on a simulated biogas plant. • Interpreting and explaining interactions of flexibility factors and the developed indicators. • Identifying bottlenecks and trade-off for flexibilization of biogas plants. [ABSTRACT FROM AUTHOR]

Abstract An important synergy exists between electricity supply security and sustainable economic development. However, distortions in the water-energy equilibrium (especially for electricity systems that heavily depend on hydropower renewable energy) and operational inefficiency in the transmission and distribution networks can affect electricity supply negatively and distort this synergy. Given the irreversible nature of capital investments and the time-dependent nature of learning abilities and information flow, it is critical to delineate the short- and long-run effects of system losses and distortions in the water-energy equilibrium on electricity availability. This study applies an econometric approach to study the case of Ghana from 1970 to 2016. Distortions in the water-energy equilibrium negatively affect electricity supply in the short- and long-run. Investment in storage renewable hydro will ensure operational flexibility and compensate for the variability in water flow. Moreover, storage hydropower is a vital asset for the development of non-flexible renewables (i.e. wind and solar) due to the synergy that exists between them. System losses have a concave effect on electricity supply, with the tolerable rate determined as 6.65%. Current levels suggest that the country should cut down on system losses by 13.35%; this requires a significant investment in transmission and distribution networks and meters. Highlights • Distortions in the water-energy equilibrium decreases electricity availability. • Storage renewable hydro should be developed in the future. • System losses have a concave effect on electricity supply with a tolerable rate of 6.65%. • Higher economic growth is compatible with the SE4ALL and energy security goals. • Recorded inefficiencies in electricity production is persistent. [ABSTRACT FROM AUTHOR]

Abstract With the increasing share of renewables in electricity generation in Europe, implied economy-wide macroeconomic feedbacks and spill-over effects to other sectors and actors are of rising importance. We quantify the macroeconomic effects of a large-scale expansion of wind and photovoltaics (PV) in Europe, employing a global multi-regional multi-sectoral computable general equilibrium (CGE) model. We place special emphasis on electricity market integration costs, which have so far been neglected not only in most bottom-up technology comparisons, but also in macroeconomic studies. We find that the societal welfare effects of a large-scale expansion of wind and PV tend to be positive; however, when integration costs are taken into account, positive welfare effects are either much smaller or even become negative, depending very much on regional characteristics, such as the prevailing electricity mix, weighted average costs of capital (WACC) or capacity factors. We also show that macroeconomic feedback effects raise generation costs above what is anticipated from a bottom-up perspective, since the high capital intensities of renewable electricity generation technologies drive up economy-wide capital prices. This may imply that they are no longer competitive when installed at large-scales. Highlights • Integration costs are a crucial factor in large scale variable renewable expansion. • Renewable expansion generally tends to increase societal welfare in EU regions. • Integration costs at high penetration rates can result in negative welfare effects. • De-risking of investment in renewables increases welfare. • Large scale renewable expansion raises capital income at the cost of labor income. [ABSTRACT FROM AUTHOR]

Abstract Evaluating the impacts related to stochastic forecast errors (SFE) of renewable energy generation and load demands on the operation of micro grid is an important issue. In previous researches, the negative effects of SFE on micro grid are mainly focusing on power quality, system control, and operation, etc. The objective of this study is to investigate how SFE affects the operation stability of energy storage system (ESS) from the perspective of the state of charge (SOC). To this end, novel SFE propagation and accumulation models are introduced. Efficient quantification models of impacts of SFE on the variance of SOC are presented. These models elucidate in detail the mechanism of ESS working from stable to unstable state due to SOC deviation. Then, some metrics are introduced to evaluate the impacts of SFE on service lifetime of units, the cycle life of ESS and operation economy of micro grid. Finally, illustrative numerical results are provided and compared using a self-developed new simulation program named MG-ROS, which can simulate the actual operation of micro grid under SFE. Highlights • Adverse impacts of SFE on the operation stability of ESS are investigated. • SFE propagation and accumulation models are introduced. • Cumulative impacts of SFE and uncertain factors on the variance of ESS SOC are quantified. • Impacts of SFE on service lifetime of MT, cycle life of ESS, and operation economy of MG are examined and evaluated. • A new simulation program MG-ROS is developed to simulate the actual operation of MG under SFE. [ABSTRACT FROM AUTHOR]

This work investigates the possibility of combining large-scale penetration (around 50% of annual demand) of variable electricity production (wind and solar power) with baseload generation of electricity (e.g., via nuclear power or coal burning). A new methodology is developed that focuses on renewable resource and variation management in combination with transmission expansion and curtailment of excess electricity generation. Using the Conditional Value-at-Risk (CVaR) measure in the objective function, the optimization model targets the residual load and tailors it to fit the baseload generation. Using Europe as an example, the results show that it is possible to tailor the residual load to fit the baseload with only a small sacrifice (∼1%) of output of generation from variable renewable energy sources (VRES). Expansion of the electricity transmission system is an important factor in accommodating baseload generation in systems with a high penetration level of VRES, whereby, for example, 50 GW of transmission capacity opens the way for baseload generation to increase from 20% to 32% of annual demand. The results show that wind power is the main contributor to VRES production, even in the case of exceptionally low future costs for solar PV. [ABSTRACT FROM AUTHOR]

Selecting a renewable energy source portfolio is an uncertain multi-criteria decision-making (MCDM) problem. In particular, it involves searching for the best portfolio of renewable energy that meets the decision maker’s preferences by considering and leveraging conflicting criteria such as technical, environmental, societal, and economic. To tackle such complex problems, this paper proposes an efficient method, called multi-segment fuzzy goal programming (MS-FGP), which addresses decision-making problems with high levels of uncertainty. The paper makes the following contributions: i) extends the conventional fuzzy goal programming (FGP) model to solve a wide range of uncertainties decision-making problems and ii) proposes a method based on a recent development in the FGP area that considers all types of fuzzy goals in real-world problems. The model is validated by applying it to a real-world scenario: optimizing the renewable portfolio for electricity generation in Italy. These renewables are solar photovoltaic (PV), wind, biomass, and tidal currents. The results show that the proposed methodology can assist decision makers in determining the most sustainable renewable energy source portfolio for electricity generation under uncertain conditions and in imprecise environments. [ABSTRACT FROM AUTHOR]

The increasing focus on the installation of sustainable energy systems has resulted in a wide range of micro wind turbine systems being introduced in the market. Although the majority of the commercially installed wind turbines are the horizontal axis ones, vertical axis turbines are considered as a promising technology for the future. It is generally known that the environmental impacts generated in the operational stage of wind turbines are significantly lower than the ones, generated by the fossil fuels based systems. The use of the Life Cycle Assessment (LCA) enables to assess the environmental impacts of a product or a process, taking into consideration also raw material extraction, manufacturing, distribution, and disposal stages of life cycle. The contribution of these stages is often critical for the environmental impacts of the bioenergy systems. This study contributes to the existing knowledge by presenting the detailed LCA of electricity produced in micro wind turbines with the vertical axis. For the impact assessment, two methods were selected: the CML-IA and Thermo-Ecological Cost in the whole life cycle (TEC-LC). Firstly, the environmental impacts of electricity generated by wind turbines with 1 and 3 kW nominal power were evaluated and compared with each other and with the impacts of the grid electricity produced in the Italian energy mix. Next, the sensitivity of the impact results on the wind characteristics variability was investigated. Results showed that the 3 kW turbine has, in general, lower values of the environmental impact indicators per unit of produced energy than the 1 kW turbine from 27% lower Global Warming Potential (GWP) to 75% lower Abiotic Depletion (ADP). The impacts per unit of produced energy in the analysed micro wind turbines are lower than the corresponding impacts for the grid electricity generated in the Italian energy mix for nine impact indicators out of twelve. It was also observed that wind distribution parameters strongly influence the environmental impacts of the electricity produced by the considered turbines, leading to values higher than those obtained for Italian energy mix for low wind average speed and, even more, for low variances of the average wind speed. [ABSTRACT FROM AUTHOR]

The current global trends demonstrate the significant role of renewable energy in meeting the growing energy demand across all sectors to support national economic growth. In Malaysia, palm oil is one of the major agricultural export commodities with a total production of 17.7 million tonnes or 41% of the total world palm oil production in 2008. This research evaluates the sustainability of the grid-connected oil palm biomass renewable energy industry in Malaysia and proposes a policy framework and industry roadmap. The factors investigated include resource supply, the efficiency of waste to energy conversion technology used in the existing plants, and the attractiveness of the electricity interconnection scheme in encouraging exports of excess power from the participating mills to the main grid. A literature review and field survey were conducted to understand the barriers and possible enhancements to the current FiT system. The study concluded that harmonisation between upstream and downstream palm oil agricultural activities is essential for achieving the goal of making the oil palm biomass waste to energy industry sustainable. The policy framework and industrial roadmap models provide a distinctive enhancement to the FiT system besides indicating the way towards a sustainable biomass to the energy industry. [ABSTRACT FROM AUTHOR]

Tidal energy is one of the most predictable forms of renewable energy. Although there has been much commercial and R&D progress in tidal stream energy, tidal range is a more mature technology, with tidal range power plants having a history that extends back over 50 years. With the 2017 publication of the “Hendry Review” that examined the feasibility of tidal lagoon power plants in the UK, it is timely to review tidal range power plants. Here, we explain the main principles of tidal range power plants, and review two main research areas: the present and future tidal range resource, and the optimization of tidal range power plants. We also discuss how variability in the electricity generated from tidal range power plants could be partially offset by the development of multiple power plants (e.g. lagoons) that are complementary in phase, and by the provision of energy storage. Finally, we discuss the implications of the Hendry Review, and what this means for the future of tidal range power plants in the UK and internationally. [ABSTRACT FROM AUTHOR]

In the study two typologies of regional units in Greece were developed that were based on their energy characteristics, such as electricity consumption in variable energy sectors–including the domestic, industrial, commercial, and agricultural– as well as the number and the respective installed power of renewable energy sources (RES) plants for electricity generation. These typologies' deployment aim at developing administrative tools that will draw the decision planning towards future energy policy in Greece. The statistical methodology adopted was a hierarchical cluster analysis. Particularly, two analyses were materialized, in line to the aforementioned energy characteristics. Under this methodological framework, the hierarchical cluster analysis resulted in four clusters, each featuring different characteristics. Specifically, in the first analysis the first cluster consists mainly of the lowest energy consumption regional units, while the fourth cluster consists mainly of the highest energy consumption regional units. Besides, the second and the third cluster consist of regional units where the RES penetration is significant, enabling the wider energy autonomy and independence from other, mainly fossil-fuelled, sources of energy production, whereas in the fourth cluster the participative role of RES in energy production was noted as very low. [ABSTRACT FROM AUTHOR]

The use of forest residue may mitigate greenhouse gas emissions by displacing the use of coal or other fossil fuels for electricity generation. However, economic viability of bioenergy requires availability of feedstock at appropriate cost. The current work attempts to quantify delivered biomass cost at plant gate and estimate cost and emission benefits to the electricity system associated with the conversion of coal units to bioenergy. This study is carried out with the optimization model OSeMOSYS, analyzing the Alberta electrical system, its mid-term coal phase-out and renewable energy targets. Alternative scenarios were compared to evaluate the effect of a biomass retrofit option on the incentives needed to achieve 30% renewable penetration by 2030. Results show that although bioenergy has a higher levelized cost than wind power, the system requires less backup capacity and less renewable energy credits to meet renewable energy goals when the biomass retrofit is allowed. In addition, the total system cost to 2060 is found to be 5% less than the scenario without the biomass option. The firm capacity provided by biomass compensates for its higher levelized cost of energy. [ABSTRACT FROM AUTHOR]

In the last decade energy security and supply has become one of the main priorities for governments around the world. Energy sources diversification, proper mix of energy generation capacities and large penetration of renewables are crucial to achieve a sustainable energy future. Smart Energy Networks (SENs) is a new concept that will allow the integration of various energy networks including electricity, gas and heat into one network under common Information and Communications Technology (ICT) to allow better management, efficient utilization and increased participation of distributed generation and renewables. In order to bridge the networks, appropriate technologies have to be applied that will allow the energy vectors to interface and share the load. One such technology is Power to Gas utilizing the excess electricity on the grid to generate hydrogen. Hydrogen then either injected in the gas pipeline/storage or used to synthesize a renewable natural gas through methanation. [ABSTRACT FROM AUTHOR]

Undoubtedly, the increasing rates of CO 2 emissions contribute highly to climate change. Studies stress the importance of understanding the determinants of emissions, in order to implement appropriate policies. In the past, literature only looked at the effect of aggregate energy to emissions; while nowadays, with the increasing role of renewables, they aim at evaluating the impacts of renewable and non-renewable energies separately. Also, studies ignored possible cross-dependence among countries; concept particularly important for countries linked by trade or geographical position. Also, only lately, studies focused on developing economies. In this study, we aim to address these gaps of the literature by estimating the determinants (renewable and non-renewable energy, income and trade openness) of CO 2 emissions for the ten biggest electricity generators in Sub-Saharan Africa for the period 1980 to 2011 by employing panel estimation techniques robust to cross dependence. A long-run relationship between the main variables is confirmed. Increases in non-renewable energy consumption intensify pollution while the opposite holds for renewable energy. With regards to direction of causal relationships, we observe a unidirectional causality running from emissions, income, trade and non-renewable energies towards renewable energies; from non-renewable energy to emissions; and from emissions and non-renewable energies to trade. [ABSTRACT FROM AUTHOR]

National and international policies recognize that the simultaneous increase in energy demand and the negative impact of fossil fuels on the environment underscore the need for energy production from renewable energy sources. This research investigated the attitudes and willingness-to-pay for electricity from renewable electricity sources of communities in Western Greece. Questionnaires were collected from over 200 households. Cluster analysis revealed the presence of two groups, the second of which contained younger, better educated, and richer respondents with a more positive attitude to renewable energy. Multiple linear regression models predicted actual electricity payments and the willingness-to-pay for renewable energy projects using socioeconomic and attitudinal characteristics. Canonical Correlation Analysis allowed simultaneous assessment of socioeconomic and attitudinal characteristics with actual electricity payments and willingness-to-pay. Age, family size, and awareness on renewable energy were the variables more strongly associated with actual electricity payments, whereas age, income, and attitudes towards the future role, impacts and obstacles to renewable energy projects were more strongly associated with willingness-to-pay. The use of willingness-to-pay analyses to provide socio-economic context to renewable electricity policy was extensively discussed. [ABSTRACT FROM AUTHOR]

The use of solar photovoltaic (PV) systems as green renewable sources for electricity generation in modern power networks is steadily increasing. One of the problems with using PV units in developing countries and small companies is access to a simple model to assess the short-time output of a solar cell. For example, a robust model that is capable of analyzing cloud variations and ambient temperature (important factors impacting the PV output) to assess short-term PV output would be very helpful. This article proposes a new methodology to assess the impacts of these factors on the hourly output power of a PV system. Our results showed that the proposed model has the ability to assess PV output by using the hourly data of cloud and ambient temperature change. To validate the model, the output was compared to results of measurements from PV systems installed in Sanandaj and Rasht cities located in North-West (latitude 35.31 and longitude 47.00) and North (latitude 37.28 and longitude 49.58) Iran, respectively. Also, the standardized root-mean-square error method (nRMSE) was used to validate the high accuracy of the proposed method. [ABSTRACT FROM AUTHOR]

Wave energy is one of the most concentrated ocean renewable energy resources. Although wave energy has been studied extensively for more than four decades, there is no large commercial installation for wave energy production or a consensus framework on how to exploit this resource. Wave energy is a complex resource that directly depends on two meteorological parameters, which produced significant fluctuations of wave energy in both temporal and spatial criteria. This paper presents a new concept called Energy Event, to analyze meteorological data generated by WaveWatch III over 36 years in the U.S. to characterize and assess wave energy behavior using the peak-over-threshold methodology. This methodology used extreme statistics, segmented the wave energy with different thresholds, and assessed wave energy production on a temporal and spatial framework. Three areas were studied in this paper, including the Gulf of Mexico, the East and West U.S. Coasts. The results indicated that wave energy behaved as a two-state energy system with each state having independent characteristics. The main difference among the three studied areas was the constant baseline of wave power density, with the West Coast having the highest constant baseline and the Gulf of Mexico having the lowest baseline. [ABSTRACT FROM AUTHOR]

This study provides a critical synthesis on the applications of nanofluids in various types of solar thermal systems. Nanofluids have received attention in recent years due to its importance in various industrial applications especially in the renewable energy field. This work presents the most recent advances of nanofluids in thermal energy storage systems, solar collectors, solar stills, and photovoltaic/thermal systems. With the application of nanomaterials, the efficiency of photovoltaic can increase substantially while reducing the production costs of electricity and manufacturing. This review is structured in three parts: the first part focuses on presenting the latest results for the thermal conductivity, viscosity, specific heat, and the thermal expansion coefficient of nanofluids reported in the literature. The second part of this review is allocated to the applications of nanofluids in different types of solar systems such as solar collectors, solar stills, thermal energy storage systems, and photovoltaic/thermal systems. Finally, the challenges and the bio-engineering safety concerns of using nanofluids in solar energy systems are discussed. [ABSTRACT FROM AUTHOR]