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The increase of Renewable Energy (RE) production to fight the climate crisis is posing new technological and financial challenges, due to the availability and variability of RE Sources (RES). These challenges can be addressed by selecting the most suitable mix of RES to optimise power production, to assure grid resilience and to promote local energy use. To facilitate the selection of such combination, this paper presents an original methodology that allows to compare mixing scenarios with different RES, also in presence of batteries and backup system. It simultaneously optimises the energy surplus with respect to the eventual external electrical load and the missing energy with respect to the same electrical load. This method, which can cope with isolated or plugged-to-grid systems, is here applied to a novel case study, an oil&gas platform under decommissioning, located in the Adriatic Sea (Italy). The RE production from wind, wave and solar panels is supposed to support other activities for the platform reuse, such as aquaculture, monitoring and mineral deposition. In this case, solar energy is providing the greatest contribution to the optimal mix in terms of production, while wave energy assures the most relevant contribution in terms of continuity. [ABSTRACT FROM AUTHOR]

This review explores the question: should the world rely wholly or partially on solar geoengineering (SG) to mitigate climate change (CC), or on renewable energy, together with deep energy reductions? Recent thinking is for SG to only supplement more conventional climate change mitigation methods. However, we first show that conventional mitigation methods are not working., given that global annual CO2 emissions are still rising, so it is far more likely that SG will be called upon to counter most anthropogenic CC, as early research proposed. The paper next examines the various SG proposals that have been considered and their objectives. Future choices could be between an increasingly unpredictable climate, and SG, with its own risks and unknowns, or deep energy reductions and RE. The claim is that SG has far lower costs for a given climate forcing reduction compared with more conventional methods, and equally important, could be quickly implemented, producing temperature reductions in a year or so, compared with decades needed for more conventional mitigation approaches. SG implementation would affect not only the technical potential for key RE sources but also the actual uptake of RE and energy reductions. However, a fair comparison of RE and SG must recognise that the SG option also requires a solution to rising ocean acidification (OA). Because the material quantities needed annually to counter OA are orders of magnitude larger than for SG, its costs and energetic requirements will also be far higher, as will the time for implementation. [ABSTRACT FROM AUTHOR]

This research paper proposes a novel multi-model approach, integrating the CARIMA-SARIMA-GPM framework, to assess the combined impacts of climate change and land use change on the potential of concentrated photovoltaic (CPV) systems. By considering both climatic variables and land use patterns, this study aims to provide a comprehensive understanding of how these factors influence CPV performance in the context of a changing environment. The proposed methodology offers valuable insights into the future viability and sustainability of CPV technology, enabling informed decision-making for policymakers, energy planners, and investors in the Middle East and Africa. As a result, the ability of the hybrid evolutionary CARIMA-SARIMA-GPM to predict the potential of CPV energy output for assessing the impacts of climate change on it was investigated in Alice Springs, the Middle East, and Africa. The outcome showed that the hybrid model significantly outperformed the other machine learning approaches. The fitted model was used to assess the potential impacts of climate change on CPV generation in Alice Springs, Australia, as well as the Middle East's and Africa's comparable climatic conditions. According to the study, climate change had the greatest impact on solar CPV energy production in Alice Springs, where it decreased the most by 8.577% under moderate forcing scenarios (SSP245) during the boreal summer season; moderately in the Middle East, where it decreased the mode by 2.316% under mitigation scenarios (SSP126) during the boreal summer season; and extremely minimally in Africa, where it decreased the mode by 1.263% under the far future sequencing period (2051–2099). Climate change also increased solar CPV energy production significantly in the Middle East in the far future sequencing period (2051–2099), as well as in Alice Springs, Australia, and Africa in the near future sequencing period (2015–2050). The strongest forcing scenario (SSP585) increased by 7.644% during the boreal autumn season in Africa; moderately increased by 6.502% during the boreal spring season in the Middle East; and had the least beneficial effects in Alice Springs, Australia, with increases of 5.538% during the boreal winter season. On an annual basis, all three regions showed a similar trend. Climate change (CLC) and urban expansion (URE) were also investigated in the Middle East and Africa for their effects on changes in solar CPV energy output. URE had a greater impact in Africa than the Middle East under the effective scenario, with a URE value of 45.45% for Africa and 20.15% for the Middle East, whereas CLC had a greater impact in the Middle East than Africa, with a CLC value of 29.01% compared to 5.47% for Africa. CLC and CPV residual factors, on the other hand, have a greater impact in the Middle East than in Africa, with effects of 29.01% and 50.83%, respectively, compared to 5.47% and 49.09%. The potential difference that drives the remediation of specific pollutants lies in the application of advanced technologies and sustainable practices. By exploring innovative solutions, such as using renewable energy sources like concentrated photovoltaic (CPV) systems, we can effectively mitigate the impacts of climate change and land use changes on pollutant concentrations. These technologies have the potential to significantly reduce pollution levels and create a cleaner and healthier environment for future generations. Assessing the CPV potential in different regions like Alice Springs, Australia, the Middle East, and Africa allows us to identify areas with high solar energy resources that can be harnessed for efficient pollutant remediation. Implementing prompt climate mitigation and adaptation measures is crucial for achieving a net-zero energy transition in the Middle East and Africa by 2050. In this context, prioritizing solar energy as the primary source of renewable energy is imperative for successful low-carbon economic planning in these regions. • CARIMA-SARIMA-GPM outperforms other applicable models • By 2100, the CPV potential in Alice Springs could increase by 0.082–5.338% at 1.5 °C • By 2100, the Middle East's CPV potential could increase by 0.021–0.221% at 1.5 °C. • By 2100, Africa's CPV potential could increase by 0.133–7.644% at 1.5 °C. • Climate change has harmed Alice Springs and the Middle East more than Africa. [ABSTRACT FROM AUTHOR]

Summary: This paper is concerned with innovative approaches to renewable energy sources computation methodologies, which provide more refined results than the classical alternatives. Such refinements provide additional improvements especially for replacement of fossil energy usages that emit greenhouse gas (GHG) into the atmosphere leading to climate change impact. Current knowledge gap among each renewable energy source calculation is rather missing fundamentals of plausible, rational, and logical explanations for the interpretation of results. In the literature, there are rather complicated and mechanically applicable methodologies, which require input and output measurement data match with missing physical explanations. The view taken in this review paper is to concentrate on quite plausible, logical, rational, and effectively applicable innovative energy calculation methodologies with simplistic fundamentals. For this purpose, a set of renewable energy methodological approaches is revisited with their innovative structures concerning solar, wind, hydro, current, and geothermal energy resources. With the increase in the renewable energy utilizations to combat the undesirable impacts of global warming and climate change, there is a need for better models that will include physical environmental conditions and data properties in the probabilistic, statistical, stochastic, logical, and rational senses leading to refined and more reliable estimations with application examples in the text. Finally, new research directions are also recommended for more refined innovative energy system calculations. [ABSTRACT FROM AUTHOR]

Abstract The main goal in this paper is to supply a national load by multiple renewable power connections to utility grid at different geographic locations. The national load demand of the country of Jordan is supplied in this case study by finding the optimal configurations and locations (near cities). Cities of higher potential for wind and/or photovoltaic (PV) energy location are selected for connecting to renewable power. The annual system cost of energy (ASCE) for this optimized renewable energy system is shown to be 32.57% less than the conventional grid energy price. Further, the Carbon Dioxide (CO 2) emissions are reduced by 80.13%. These are excellent indications for the feasibility and environmental benefits of retrofitting conventional grid with renewable power in developing countries. Multi-figure of merits (MFOM) based on a Nondominated Sorting Genetic Algorithms (NSGA) optimization cases are investigated which include annual emission indicator (AEI), ASCE, levelized cost of energy (LCOE) and renewable penetration (RP). Results are either two dimensions (2D) or three dimensions (3D) Pareto frontier, where various competitive non-dominant solutions exist. A sweet spot selection (triple-S) procedure is proposed to help select the best point in the two (figure of merits) FOMs Pareto frontier to have both environmental and feasible solutions. Highlights • The contributions of this paper are multi-point connection to a national grid, holistic definition and modeling of the engineering and financial problems, optimal design tool solutions to the multi-point connection problem definition and model, suggesting this as a case study of the concept of "local solutions for a global problem." Such a holistic approach is recommended especially in the developing countries. • The importance of moving toward sustainable energy stems from global climate change and the need to provide access to affordable energy to all of humanity. The ultimate goal is to satisfy a country's national load demand by establishing multiple utility grid connections to various geographic locations of high wind or solar energy resources. This is done by building a new optimization design tool which investigates economic feasibility and environmental impacts. Then, Single figure of merit and multi-figure of merits optimizations have been investigated. • A mathematical modeling is developed for each component, and the optimal configuration is determined for each city. The annual system cost of energy (ASCE) is optimized to be 32.57% less than grid energy price, and the CO 2 emissions (AEI) are reduced by 80.13%. These are excellent indications for the economic feasibility and the environmental benefits of the designed system. The levelized cost of energy (LCOE), total net present cost, renewable penetration (RP) and AEI are 0.058212 $/kWh, $8.713857 billion, 59.49817% and 4.576 Megatonne/year respectively. • A new equation to calculate the salvage cost has been developed in this paper. Moreover, a new procedure in a multi-optimization problem was developed in this paper, which is the Sweet Spot Selection (triple-S) procedure. It is developed to help select the sweet point in the two FOMs Pareto frontier to have both environmental and economic feasible solutions. • Multi-figure of merits (MFOM) optimization cases based on a non-sorting genetic algorithm are investigated such as: AEI vs. ASCE, AEI vs. LCOE, AEI vs. RP and (RP, LCOE, AEI). The MFOM optimization results are either 2D or 3D Pareto frontier, where exists various competitive non-dominant solutions. The sweet spot selection (triple-S) procedure is proposed to help select the sweet spot in the two figure of merits Pareto frontier in order to have both environmental and feasible solutions. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • This paper presents a detailed review of sustainable water desalination by using solar membrane distillation. • The fundamental of membrane distillation and the different configuration of solar membrane distillation have been discussed. • The recent developments and potential improvement of solar membrane distillation have been discussed in this paper. • The research gaps are highlighted for future improvement. Abstract As the water demand increases continuously, large capacities of desalination plant are added every year to meet freshwater demand. The higher carbon footprint of desalination raises concern on global climate change. The integration of desalination and renewable energy source could mitigate this water-energy nexus. Membrane distillation (MD) is a non-isothermal desalination process in which the low-grade heat is used as the driving force. Many researchers have tried to integrate solar energy and MD for sustainable water desalination. This article presents a comprehensive review of solar MD desalination to understand its current state of development. Solar powered MD systems have been investigated for last few decades. However, its commercialization is very limited due to low flux, high specific energy consumption and large collector area requirement. Further, this review presents the recent developments in MD membrane, innovative MD modules and the importance of optimization, which was able to improve the performance of solar MD. [ABSTRACT FROM AUTHOR]

Summary: The produced energy from varied sources in modern power systems is to be optimally planned for planning and operating of power system under the determined limit conditions. Recently, the rising overall people population of the world, the increasing of people requirements, improvements of technology, and ecosystem and global climate changes have caused with the increasing of electric energy demand. One of the most important solution methods to meet this energy demand is considered as utilization of renewable energy sources (RESs) in power systems. The structure of power systems has become with the usage of RESs more complex. The optimal power flow (OPF) from planning and operation problems has converted to difficult problem with RESs integrated into modern power systems. This paper presents the OPF problem of power systems with a high penetration of controllable renewable sources. These kinds of sources are able to inject a determined power since they have a back‐up unit (storage). Uncertain solar irradiance and wind speed are simulated via log‐normal and Rayleigh probability distributions, respectively. The proposed OPF problem with controllable renewable sources is solved by the differential evolutionary particle swarm optimization (DEEPSO) algorithm. Simulations conducted on various test systems illustrate the effectiveness and efficiency of DEEPSO as compared with other algorithms including moth swarm algorithm, backtracking search algorithm, and differential search algorithm. In addition, the Wilcoxon signed‐rank test is applied to show the supremacy, effectiveness, and robustness of DEEPSO algorithm. [ABSTRACT FROM AUTHOR]

Renewable energy is becoming an essential element when it comes to climate change greenhouse issues. To aid in reducing the CO2 emission into the environment, numerous governments support individual investments in solar system on their residential rooftop. A set of regulations were established by the local utilities to control and manage the input energy power into the grid from the rooftop-installed solar system. One of the main regulation is the maximum allowable size of the single-phase solar inverter. The solar inverter size has direct impact on the maximum PV panels installed on the house rooftop, which control the house maximum electrical output power. In addition, the solar panels are solidly fixed on the house roof, which doesn’t allow to track the sun energy during the day. This also reduces the house output power during a nominal period throughout the day. The study in this paper introduces the maximum power point box that allow the house owner to maximize the output energy during the morning, midday and afternoon period without the need to upgrade the inverter or the single phase system for the house. Also the proposal allows for more efficient building integration between solar panels and building design, which reduces the cost of the proposed system. Case study is also included. [ABSTRACT FROM AUTHOR]

With ever-increasing demands for energy and gradual climate changes, development and advancements of renewable energy have become a major priority of every country. The applications of renewable energy increase many folds when coupled with wireless power transfer (WPT) technology. About a century ago the advents of Tesla provided us with the principles of WPT. Since then a lot of research has been done in this field. Many efforts have been put to transmit power of renewable energy wirelessly. In this paper, the basic principles and various methods of WPT are reviewed and also discuss the recent developments in wireless transmission of renewable energy. An update for application and limitations of WPT has been presented. The possible systems produced with the coupling of WPT are also presented. [ABSTRACT FROM AUTHOR]

Several theoretical studies have been reported in recent years which have indicated that large-scale wind farms can have an impact on local and regional meteorology, possibly on climate. Now evidence of it based on field observations has also begun to emerge. The present paper traces the evolution of this knowledge. It discusses the theoretical studies on the possibility of wind turbines effecting climate change, and summarizes the emerging confirmation of those predictions. The concluding part of the paper assesses the implications of these findings in the context of the world׳s past experience on global warming and its present thrust to meet substantial portions of its energy needs with renewables. [ABSTRACT FROM AUTHOR]

This paper describes large scale tests conducted on a novel unglazed solar air collector system. The proposed system, referred to as a back-pass solar collector (BPSC), has on-site installation and aesthetic advantages over conventional unglazed transpired solar collectors (UTSC) as it is fully integrated within a standard insulated wall panel. This paper presents the results obtained from monitoring a BPSC wall panel over one year. Measurements of temperature, wind velocity and solar irradiance were taken at multiple air mass flow rates. It is shown that the length of the collector cavities has a direct impact on the efficiency of the system. It is also shown that beyond a height-to-flow ratio of 0.023 m/m³/hr/m 2 , no additional heat output is obtained by increasing the collector height for the experimental setup in this study, but these numbers would obviously be different if the experimental setup or test environment (e.g. location and climate) change. An equation for predicting the temperature rise of the BPSC is proposed. [ABSTRACT FROM AUTHOR]

It is clear that developing countries will have to be part of the global mitigation effort to avoid ‘dangerous climate change’, and, indeed, many of them are already undertaking significant actions on multiple fronts to help address this problem, even if they have not yet taken on legally binding commitment under the United Nations Framework Convention on Climate Change (UNFCCC). Since the deployment of GHG-mitigating technologies is already a significant part of this effort and likely to be even more so in the future, drawing lessons from existing programmes can help accelerate and enhance the effectiveness of this deployment process. Accordingly, this article aims to examine the deployment of wind and solar power in India, paying specific attention to the role of public policy in incentivizing and facilitating this deployment, how these policies have evolved over time, what has shaped this evolution, and what the learning has been over this period. Through this analysis, the intention is to draw out key lessons from India's experience with deployment policies and programmes in these two sectors and highlight the issues that will need to be given particular consideration in the design of future domestic policies and international cooperation programmes to enhance the move towards climate-compatible development in India. Many of these lessons should also be relevant for other developing countries that are attempting to balance their climate and developmental priorities through the deployment of renewable energy technologies. [ABSTRACT FROM AUTHOR]

Deployments of renewable energy technologies in the current century represent a critical approach to sustainable development. Renewable energy can be generated from sources with the backdrop to restock themselves based on timescale. The most important sources of renewable energy include solar photovoltaic conversion technologies, biomass and biofuel energy systems, wind energy turbines, geothermal energy technologies and hydroelectric power systems. Considerable investment in renewable energy in a country can lower the nation's dependency on imported fuels and purchase of energy from foreign market. It also drives technological innovation and generate employment scheme while enhancing clean development mechanism. Consequently, this paper presents the existing renewable energy technologies in the Nigeria and as well makes some critical recommendations to further induce development of renewable and sustainable energy systems based on autonomous energy systems and microgrid (µgrid) technologies. The recommendations are made based on varieties of energy technologies for solar power generation, biomass and bioenergy, wind energy, hydropower generation and the combined generation systems using hybrid energy mechanism. The structure of the study is concluded based on suggestions on how to pursue some impending socio-political, technological, investment policy and legislative issues for effective renewable energy development in the country. [ABSTRACT FROM AUTHOR]

Nowadays, climate change has become a vital issue prompting investigations for increasing the share of renewable energy employment in power generation industry. Solar energy is arguably the most favorable solution for a greener power generation technology. With the current level of maturity, solar energy contribution is limited due to intermittency and storage issues. A possible solution to the aforementioned difficulties is power plant hybridization. In this paper, thermo-economic optimization of a hybrid air bottoming cycle (ABC) power plant is accomplished with the objective of minimizing the levelized cost of electricity. The aforementioned hybrid ABC optimization results are compared with a hybrid conventional combined cycle power plant to identify the most cost effective combined cycle configuration for a 50 MWe hybrid power plant. Finally, an already existing ABC power plant hybridization is investigated utilizing payback period, life cycle saving, and levelized cost of electricity approaches. [ABSTRACT FROM AUTHOR]

The mitigation of global energy demands and climate change are the most important factors in the modern days. Development and application of solar energy have been regarded by the government of India and common people, and they thought that solar photo voltaic energy can provide more energy in future compare to other renewable energies. In the last decade, solar photovoltaic energy research and development has supported by the central government and state governments. This paper discusses the progress of current solar photovoltaic energy in India. It highlights the renewable energy trend in India with major achievements, state wise analysis of solar parks and industrial applications. Finally, it discusses the Indian government policies and initiatives to promote solar energy in India. This review on solar photovoltaic energy will help decision makers and various stakeholders to understand the current status, barriers and challenges for better planning and management in this field. [ABSTRACT FROM AUTHOR]

The paper presents a cradle-to-grave life cycle assessment for two domestic solar hot water systems. The first consists of polypropylene unglazed solar panels coupled with a 300-l storage tank; the second one consists of a traditional system with glazed solar panels coupled with a thermal storage of the same volume. Life cycle assessment was conducted according to the Eco-Indicator 99 methodology, Egalitarian Approach, yielding 49.7 and 18.3 eco-indicator points for the glazed and unglazed panels systems, respectively. In addition, for each domestic solar hot water system, the energy, CO 2 and economic payback times were calculated. In order to take into account the influence of local climate on the solar panels yield evaluate, the systems performance was simulated for three different locations: Rome, Madrid and Munich. The payback times were evaluated with respect to both natural gas and electrical boilers. The Energy Payback Time of the unglazed panel system ranges between 2 and 5 months, that of the glazed panel between 5 and 12 months. The CO 2 Payback Time of the unglazed panel system ranges between 1 and 2 months, that of the glazed panel between 12 and 30 months. The economic payback time, if compared with natural gas boiler, is in the range 9–11 years/8–13 years for the system with unglazed/glazed panels, respectively; if compared with the electrical boiler, it is in the range of 3–4 years for the system with unglazed panels and 4 years for that with glazed panels. The different national costs of natural gas and/or electricity play an important role in the economic payback times. Indeed, in Munich, the smaller energy savings achieved with the renewable systems are offset by the higher costs of these commodities. [ABSTRACT FROM AUTHOR]

India has tremendous potential for generating clean electricity through Renewable Energy Sources (RES) namely Hydro, Wind and Solar. This potential has been duly recognized and shows India׳s consciousness for reducing carbon footprint as a developing nation. Government of India with an aim to promote clean energy launched Jawaharlal Nehru National Solar Mission (JNNSM) on 11th January 2010, which is one of the eight missions under National Action Plan on Climate Change (NAPCC–2008). This mission visions to install 22,000 MW through grid connected and off grid power plants. Achieving an installed capacity of this quantum is a task full of challenges. To list the possible challenges and suggest a way forward, there is a need to study solar energy sector in India in the past, which has motivated the authors to discuss the evolution of solar energy in India since independence. Through this paper authors have tried to outline the journey of solar energy in India since 1950 till date and highlight the potential issues as barriers and challenges which could impact the ambitious mission taken up by Government of India. This study will help decision makers and various stakeholders to understand the current status, barriers and challenges for better planning and management in the field of solar energy. [ABSTRACT FROM AUTHOR]

Solar energy use in the UK is increasing dramatically, providing both heat energy and generation of electricity. This trend is expected to continue due to solar technologies becoming cheaper and more readily available along with low carbon government legislation such as the Renewable Heat Incentive (RHI) and Feed in Tariffs (FiTs) supporting solar energy deployment. However, the effects of climate change on the solar resource remain largely unstudied. Climate change affects cloud cover characteristics and consequently directly affects the performance of solar energy technologies. This paper investigates the UK solar irradiation resource for both the present and future climates. The present solar irradiation level was assessed through the conversion of 30 years of observed historical monthly average sunshine duration data. The method and results are validated by comparing the converted solar irradiation levels to actual solar irradiance measurements at weather stations with significant historical records of solar irradiance data. The impact of climate change is investigated across different regions of the UK by using the UKCP09 probabilistic climate change projections. We find that the current average UK annual solar resource is 101.2 Wm −2 , ranging from 128.4 Wm −2 in the south of England to 71.8 Wm −2 in the northwest of Scotland. It seems likely that climate change will increase the average resource in the south of the UK, while marginally decreasing it in the Northwest. The overall effect is a mean increase of the UK solar resource, however it will have greater seasonal variability and discrepancies between geographical regions will be reinforced. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this paper is to analyze the role of renewable energy technologies (RETs) such as biogas, improved cooking stoves (ICSs), micro hydro (MH) and solar power (SP) in helping rural communities in Nepal to adapt to climate change. The analysis considers the energy efficiency of different RETs as well as their socio-economic and environmental impacts. The efficient use of biomass in new technology, such as biogas and ICSs for cooking, has increased energy security and reduced the negative effects of traditional biomass usage. MH and SP systems are replacing candles and kerosene lamps, and are the most promising RET models for electricity generation in rural Nepal. The improved illumination from these technologies also produces better education, health, environments, and social harmony in rural communities. This study uses the Long-range Energy Alternatives Planning model (LEAP) model to develop a plan for long-term RETs use in Nepal, and specifically focuses on household energy use in rural areas. It assesses the role of biogas and ICSs in rural communities and climate change adaptation in Nepal, along with the potential role of MH and SP technologies. According to the LEAP analysis, the planned implementation of MH for 20-year long-term will result in the reduction of 2.553 million tons of CO2 emissions. Similarly SP, biogas, and ICSs will result in a reduction in CO2 emissions of 5.214 million tons, 35.880 million tons, and 7.452 million tons, respectively. [Copyright &y& Elsevier]

The current editorial summarized some of the scientific works presented in the Sustainable Energy and Environmental Protection (SEEP) conference-held at the University of the West of Scotland, UK, 2018. The selected work was directly related to the scope of the Renewable, Sustainable Energy Reviews (RSER) journal. During the conference activities, experts from all around the world in the subjects of: renewable energy, climate change, optimization, and economics presented and discussed the progress made in renewable energy sources, as well as the new strategies for protecting the environment from the hazards connected with fossil fuel utilization. The methods presented in the conference focused on several directions: the development of efficient energy conversion systems with low/no environmental impacts; the suggested policies to widespread renewable energies; the restriction in the emission of greenhouse gases, and the recent progresses in CO 2 capture. This editorial focused on the renewable energy developments and their positive effect on the climate change, and briefly summarized the accepted manuscripts in this issue. • Effects of renewable energy on climate change. • Background on the International Conference on Sustainable Energy and Environmental Protection SEEP. • Summary of selected papers of SEEP 2018. [ABSTRACT FROM AUTHOR]

The current editorial summarized some of the scientific works presented in the Sustainable Energy and Environmental Protection (SEEP) conference-held at the University of the West of Scotland, UK, 2018. The selected work was directly related to the scope of the Renewable, Sustainable Energy Reviews (RSER) journal. During the conference activities, experts from all around the world in the subjects of: renewable energy, climate change, optimization, and economics presented and discussed the progress made in renewable energy sources, as well as the new strategies for protecting the environment from the hazards connected with fossil fuel utilization. The methods presented in the conference focused on several directions: the development of efficient energy conversion systems with low/no environmental impacts; the suggested policies to widespread renewable energies; the restriction in the emission of greenhouse gases, and the recent progresses in CO 2 capture. This editorial focused on the renewable energy developments and their positive effect on the climate change, and briefly summarized the accepted manuscripts in this issue. • Effects of renewable energy on climate change. • Background on the International Conference on Sustainable Energy and Environmental Protection SEEP. • Summary of selected papers of SEEP 2018. [ABSTRACT FROM AUTHOR]

This paper discusses a structural property for a power system to continue a safe operation under power fluctuation caused by fluctuating power sources and loads. Concerns over global climate change and gas emissions have motivated development and integration of renewable energy sources such as wind and solar to fulfill power demand. The energy generated from these sources exhibits fluctuations and uncertainty which is uncontrollable. In addition, the power fluctuations caused by power loads also have the same consequences on power system. To mitigate the effects of uncontrollable power fluctuations, a power flow control is presented which allocates power levels for controllable power sources and loads and connections between power devices. One basic function for the power flow control is to balance the generated power with the power demand. However, due to the structural limitations, i.e., the power level limitations of controllable sources and loads and the limitation of power flow channels, the power balance may not be achieved. This paper proposes two theorems about the structural conditions for a power system to have a feasible solution which achieves the power balance between power sources and power loads. The discussions in this paper will provide a solid theoretical background for designing a power flow system which proves robustness against fluctuations caused by fluctuating power devices. [ABSTRACT FROM AUTHOR]

Renewable energy plays a crucial role in both climate change mitigation and adaptation in highly climate-vulnerable nations such as Nepal. This paper reviews various types of renewable energy technologies and their status, potential for adoption, relationship to climate change, and mitigative and adaptive roles in Nepal. Nepal has installed micro-hydro projects, solar power, improved cooking stoves, biogas technology, improved water mills, and wind energy to mitigate and adapt to climate change. There is a growing potential for renewable energy development in Nepal, such as hydropower, solar, wind energy, biogas, and improved cooking stoves. Roughly 70% of Nepal's energy consumption is generated from traditional energy sources while renewable energy accounts for approximately three percent. The gradual increase in the use of renewable energy has reduced greenhouse gas emissions and enhanced carbon sequestration. By adopting renewable energy technologies, Nepal has reduced emissions by 221,129 tCO 2 e from 2017 to 2018. Nepal's second Nationally Determined Contribution targets a 15% increase in national energy use from renewables with a reduction of 23% of CO 2 emissions by 2030 using biogas and improved cooking systems. Furthermore, a significant increase in the adoption of renewable energy has become a pivotal strategy in adaptation to climate change in social, health, and economic sectors resulting in time savings, alternative income sources, improved health and educational status, local job opportunities, and the promotion of social capital. The benefits of adapting to climate change and mitigating CO 2 emissions via renewable energy are significant at the local, national, and international levels. This study recommends that the government of Nepal focus work on energy policy reviews to address local energy demand and climate change issues by utilizing renewable energy resources at the local level, which has global implications. • Suitable, potential renewable energy technologies in Nepal. • The relationship between energy and climate change. • Relevant data on energy and climate change in tables and figures. • Social, economic, and environmental benefits of renewable energy. • Climate change adaptation and mitigation via renewable energy. [ABSTRACT FROM AUTHOR]

The penetration of renewable energies has increased during the last decades since it has become an effective solution to the world's energy challenges. Among all renewable energy sources, photovoltaic (PV) technology is the most immediate way to convert solar radiation into electricity. Nevertheless, PV power output is affected by several factors, such as location, clouds, etc. As PV plants proliferate and represent significant contributors to grid electricity production, it becomes increasingly important to manage their inherent alterability. Therefore, solar PV forecasting is a pivotal factor to support reliable and cost-effective grid operation and control. In this paper, a stacked long short-term memory network, which is a significant component of the deep recurrent neural network, is considered for the prediction of PV power output for 1.5 h ahead. Historical data of PV power output from a PV plant in Nicosia, Cyprus, were used as input to the forecasting model. Once the model was defined and trained, the model performance was assessed qualitative (by graphical tools) and quantitative (by calculating the Root Mean Square Error (RMSE) and by applying the k-fold cross-validation method). The results showed that our model can predict well, since the RMSE gives a value of 0.11368, whereas when applying the k-fold cross-validation, the mean of the resulting RMSE values is 0.09394 with a standard deviation 0.01616. [ABSTRACT FROM AUTHOR]

Solar energy harvesting using Photovoltaic (PV) systems is one of the most popular sources of renewable energy, however the main drawback of PV systems is their low conversion efficiency. An optimal system operation requires an efficient tracking of the Maximum Power Point (MPP), which represents the maximum energy that can be extracted from the PV panel. This paper presents a novel control approach for the Maximum Power Point Tracking (MPPT) based on the differential flatness property of the Boost converter, which is one of the most used converters in PV systems. The underlying idea of the proposed control approach is to use the classical flatness-based trajectory tracking control where a reference voltage will be defined in terms of the maximum power provided by the PV panel. The effectiveness of the proposed controller is assessed through numerical simulations and experimental tests. The results show that the controller based on differential flatness is capable of converging in less than 0.15 s and, compared with other MPPT techniques, such as Incremental Conductance and Perturb and Observe, it improves the response against sudden changes in load or weather conditions, reducing the ringing in the output of the system. Based on the results, it can be inferred that the new flatness-based controller represents an alternative to improve the MPPT in PV systems, especially when they are subject to sudden load or weather changes. [ABSTRACT FROM AUTHOR]

Solar energy constitutes one of the most effective alternative energy sources for combating climate change. However, the solar potential in a city can vary depending on the urban morphology. The purpose of this paper is to perform a directional statistical analysis of the distribution of the monthly solar potential of rooftops in the city of Cáceres, Spain, in relation to the orientations and slopes of the rooftops. Two residential areas, one in the city center and one on the outskirts of the city, and an industrial zone, all of which exhibit different urban morphologies, have been evaluated. Statistics have been assessed in consideration of the orientation and slope values of the rooftops as circular data, and the radiation values as linear data. The three dissimilar urban morphologies result in different solar potential values, and the monthly disaggregation of the data enables the ability to detect the differences existing in the solar potential between each zone, during each month. The proposed analysis could also be extrapolated to urban planning for the design of more sustainable cities to face the challenges associated with climate change. [ABSTRACT FROM AUTHOR]