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Malaysia is one of the leading producers and exporters of oil palm, and the industry contributes significantly to the growth of the national economy. Nonetheless, the consequential oil palm biomass (OPB) with a potential yield of ∼97 million tonnes annually presents both challenges and opportunities, demanding innovative waste management solutions. This paper explores the feasibility of converting OPB into valuable commodities by employing concentrated solar-driven pyrolysis. A detailed overview of the biomass produced from oil palm plantations and mills is provided, along with a discussion of the industry stakeholders and associated biomass management challenges. The pyrolysis of OPB is explored, emphasizing benefits, potential barriers, and techniques. The focus then shifts to Malaysia's solar potential, which ranges from 1470 to 1900 kWh/m2 annually. The potentials of solar pyrolysis are explored, encompassing discussions on solar concentrator types, reactors, and the distribution of solar and OPB resources throughout Malaysia. The paper then recommends Tawau in Sabah, as an ideal location for OPB solar pyrolysis, due to its solar availability (up to 1873 kWh/m2), potential OPB resources from 19 mills and 241 plantations, and supportive infrastructure. The paper proposes solar-driven pyrolysis as a sustainable solution for Malaysia's OPB management, offers insights for policy initiatives and technological innovations in optimizing OPB and solar energy utilization. • Analyzes oil palm biomass potential for solar pyrolysis in Malaysia. • Explores solar resources in Malaysia for solar-driven pyrolysis. • Examines solar concentrators and reactors for pyrolysis. • Identifies potential city, as the optimal location for solar pyrolysis. • Discusses commercialization challenges of solar-driven pyrolysis. [ABSTRACT FROM AUTHOR]

This paper presents a systematic literature review of solar energy studies conducted in Nordic built environments to provide an overview of the current status of the research, identify the most common metrics and parameters at high latitudes, and identify research gaps. 55 publications are included in the review and categorized according to three main urban spatial domains: (i) outdoor, (ii) envelope, and (iii) indoor. In addition, a category for publications investigating more than one spatial domain (multi-domain) is included. The first part of the paper presents a publication analysis of keywords, history and methods, channels, citations, geographical distribution, and spatial domain coverage. In the second part, the main findings for each urban spatial domain are presented and discussed. The results show that the majority of the studies applied numerical methods in their workflow and the envelope is the most researched spatial domain, with studies focusing either on the potential exploitation of solar energy through active solar systems, or the prediction of indoor daylight conditions by using the façade as a proxy for the indoor domain. Among the main findings, urban density, building morphology, and orientation are the most utilized parameters, while solar irradiation and direct sunlight are the most common metrics. This review paper reveals significant research gaps in the field of solar accessibility in high-latitude Nordic built environments: (i) numerical studies that simultaneously address and interlink all three urban spatial domains are missing; (ii) deeper investigation of the outdoor domain is needed. • Growing interest in the field of solar accessibility in high-latitude urban areas. • Urban density, building morphology and orientation identified as common parameters. • Solar irradiation and direct sunlight identified as the most utilized metrics. • Most researched urban spatial domain is the envelope while outdoor is the least. • Significant gap in the research of numerical studies overarching multiple domains. [ABSTRACT FROM AUTHOR]

By exploiting the 3 K coldness of outer space as heat sink of terrestrial thermal radiation, passive daytime radiative cooling (PDRC) can achieve sub-ambient temperatures without any energy consumption, and thus exhibiting extraordinary application potentials. By pursuing the dual-band (solar and atmosphere window) optical properties to approach ideal 100 %, PDRC can maximize dissipating long wavelength infrared radiation to space and minimize absorbing sunlight simultaneously. PDRC technology can reach146 W/m2 theoretical cooling power and up to 120 W/m2 during application. This article focuses on the fundamental physics mechanism of radiative transfer and natural radiative cooling phenomena. Methodologies of infrared absorption functional group selection, optical band gap selection for solar reflection, photon and phonon enhanced resonance by micro-structure were discussed in detail to give a comprehensive instructing strategy of radiative cooling power improvement. Although PDRC technology can achieve sum-ambient temperature cooling without consuming any energy, its drawbacks such as single function of cooling and high whiteness requirement needed to hinder its large-scale application. This article also outlines the current primary applications of PDRC technology, along with summarizing the challenges and potential opportunities it encounters in practical implementation. This paper aims to provide a comprehensive overview on the fundamental physical mechanisms, methods for enhancing its power output, as well as the current state and future developments of PDRC applications, providing potential guidance for reducing greenhouse gas emissions and energy consumption. • Advancements of radiative cooling technology were reviewed comprehensively. • Fundamental physics of passive radiative cooling was reviewed comprehensively. • Material selection methodology and optical mechanism were discussed in detail. • The recent application of passive daytime radiative cooling was reviewed. • Some current challenges and potential applications were presented and discussed. [ABSTRACT FROM AUTHOR]

This paper provides a review of negative carbon capture technologies. Based on these technologies, here it is proposed an innovative negative emissions power plant combining the generation and storage of energy from biomass, photovoltaic, and concentrated solar power, capturing and recovering CO 2 by producing H 2 or CH 4 as green energy carriers. The main features of the system are i) large-scale energy production system with negative CO 2 emissions; ii) 100% renewable system based on biomass and solar energy with the possibility of integrating other renewables; iii) synergistic integration of processes and systems; iv) recovery of O 2 generated by photovoltaic-driven electrolysis within the process of partial biomass oxycombustion and v) solar-driven limestone calcination. A detailed model of the entire plant is developed to evaluate the integration of the process. The model performance is assessed on an hourly basis throughout the whole year. The base case results show an energy consumption from 1 to 2.1 MJ/kg CO 2 to capture 60–77% of CO 2 emitted from the biomass plant and green methane production of more than 7500 tons/year. The negative emissions associated with the process are -612 kg CO 2 /MWh. It justifies the interest in the proposed negative emissions power plant. [Display omitted] • A synergetic integration of CO2 capture, energy storage and methane production is proposed. • A biomass power plant is considered, resulting in -612 kg CO2/MWh negative emissions. • Solar PV and CSP are integrated into the process to reduce the SPECCA to 1–2.1 kg CO2/MWh. • A large amount of solids storage is required to achieve 70–90% CO2 capture capacity. [ABSTRACT FROM AUTHOR]

Solar energy is considered the most promising form of renewable energy due to its abundant reserves, widespread availability, and minimal environmental impact. However, the traditional PV (Photovoltaic) systems cannot achieve high electrical efficiency because of the technical restrictions of solar cells and high maintenance costs also hinder the large-scale popularization of PV system. The appearance of CPV (Concentrated Photovoltaic) systems solve the above problems, increasing the electrical efficiency to a great extent, but appropriate cooling technologies are of great need to decrease the cell surface temperature under high heat flux density caused by concentrators. This paper provides a comprehensive review of the different photovoltaic systems and corresponding cooling technologies, detailed investigating the distinctions, applicability, development trend and future technologies of both passive and active cooling methods. The analysis will shed light on the advancements made in increasing efficiency of crucial solar systems, as well as the importance of effective cooling techniques to maintain optimal performance in crucial solar systems. • The development of crucial solar systems and the corresponding cooling technologies are reviewed and discussed. • The focus is on the comparison and analysis of cooling technologies for CPV/T systems. • Spray cooling is one of the optimal cooling techniques for HPCV/T systems. • The application of nanotechnology improves the uniformity of temperature field of solar cells and heat transfer performance. • The challenges and opportunities associated with CPV system cooling technology are considered. [ABSTRACT FROM AUTHOR]

In the context of carbon neutrality, renewable energy, especially wind power, solar PV and hydropower, will become the most important power sources in the future low-carbon power system. Since wind power and solar PV are specifically intermittent and space-heterogeneity, an assessment of renewable energy potential considering the variability of wind power and solar PV with high temporal resolution in different regions will facilitate more accurate identification of the decarbonization pathway of power system. In this paper, the complementary output potential of wind-solar-hydro power every 15 min in 31 Chinese provinces is evaluated by developing a multi-objective optimization model based on Nondominated Sorting Genetic Algorithm II. The results show that the total annual complementary power generation potential in China is 17.57 PWh, of which the three components account for 47.8%, 25.3% and 26.9%, respectively. Inner Mongolia and Tibet are the major renewable energy source provinces with annual complementary power generation potential of 5330 TWh and 3907 TWh, accounting for 30.3% and 13.7% of the total power generation potential, respectively. The temporal potential of wind-solar-hydro power varies greatly, with daily potential is more volatile than monthly. Seasonal and spatial heterogeneity of the complemental renewable potential makes some provinces suffer power shortage during long-hours period especially in winter. Our findings will encourage a higher penetration of renewable energy, the promotion of multi-energy complementarity, and the development of inter-provincial power transmission and energy storage infrastructure in China's future power sector. • A multi-objective wind-solar-hydro complementary optimization model is developed. • Electricity supply and demand have gaps at different temporal and spatial scales. • Wind-solar-hydro complementary potential shows great temporal and spatial variation. • Renewable complementarity can improve China's future power system stability. [ABSTRACT FROM AUTHOR]

The Sun is the star in our solar system that beams solar energy towards the Earth, shining it during the day. The researcher discovered different ways to enhance the use of solar radiation to meet daily need because they are aware of how abundant it is. The thermal performance of double pass solar collector (DPSC) is higher compared to flat plate solar collector (FPSC) when comparing their thermal efficiencies. There have been several studies done on the experimental and theoretical analysis of DPSC, where different kind of tests have been carried out on different aspects. This paper aims to reviews recent development (5 years) on double pass solar collector (DPSC) where it highlights the improvement methods, functioning parameters, materials used, and design configurations. By reviewing experimental and theoretical analysis on the double-pass collector with various thermal transfer enhancement, it can help the researchers to keep updated on new development of the double-pass collector. Several methods to improve the convective heat transfer for the system were adding fins, phase change material (PCM), improved absorbers and porous media to the DPSC. Other important things that require improvement are increasing the outlet temperature, efficiency enhancement for DPSC and pressure drop reduction. The effect of using various mass flow rates, solar radiation, temperatures and working fluid on DPSC are also discussed. We wrap this review by identifying numerous applications that are possible for the solar air heating such as space heating and conditioning, water desalination process and drying agricultural food product. • Adding phase change material (PCM), can enhance thermal efficiency for double pass solar collector. • Fins can increase convective heat transfer. • Porous media can accelerate the performance of double pass solar collector. • Adding tubular on absorber can helps to increase the heat efficiency. • New novelty double pass solar collector has been found for the last 5 years. [ABSTRACT FROM AUTHOR]

In the context of the European Green Deal and the Recovery Plan for Europe, CSP can play its role, by providing dispatchable and flexible energy when other renewable technologies cannot. The aim of this paper is to identify the potential socioeconomic, social and environmental impacts associated to the future deployment of CSP projects in Spain, taking into account the global value chain. Based on an extended multiregional input-output model developed by the authors, this paper identifies the country and sector-origin of nine sustainability indicators for the two dominant CSP technologies (parabolic trough and central receiver). The research considers the deployment of a 200 MW CSP power plant in Spain to compare the sustainability impacts of these two technologies under three different scenarios regarding the country-origin of the main components. The results show that central receivers have more positive economic impacts, both in terms of value added and employment creation, and lower negative environmental and social impacts than the parabolic trough alternative. The economic and environmental impacts of the CSP deployed in Spain depend on the origin of components, with the highest negative environmental impacts occurring when the components come from China and the lowest when they come from Germany. The same occurs for the social impacts and supply risks, which are lower when Germany supplies the main components. The scenario in which Spain supplies all the components performs better than the Chinese supply scenario in terms of social risks, whereas no major differences among them were found on supply risks. • CSP deployment in Spain will have socioeconomic benefits, mostly retained in Europe. • CSP electricity has low silver extraction and carbon and water footprints compared to other energy sources. • Chinese penetration in the European CSP market worsens the sustainability of plants. • The best sustainability performance occurs in the European cooperative scenario. • There are tradeoffs between the sustainability impacts driven by the CSP investments. [ABSTRACT FROM AUTHOR]

Modern urban architecture is innovative, involves integrated solar technologies to increase sustainability, by providing efficient energy solutions, and involves stakeholders from multiple domains, with specific concerns. Such development, however, leads to complex interrelationships among disciplines and relies on models to simulate different aspects. To address these, the parametric design approach is widely adopted, enabling the generation of several urban designs in the early stage, and evaluating these across several objectives. This provides possibilities for creating collaborative, multi-disciplinary workflows for energy projects at different scales. This paper provides a critical overview of the possibilities offered by the parametric design, to increase the sustainability of advanced buildings, by putting a focus on solar energy. This paper analyses the parametric design across five categories: design scope, application, technology, objective, and implementation method. No review article currently highlights all these aspects to observe overall research in the field. The results indicate that the parametric design is prominent on a single building-scale, while windows in building-scale and building forms in district-scale models are widely manipulated parameters. Most models are limited to BIPV, shader, and solar façade technologies, daylight and solar power applications, and energy and comfort-related objectives, the majority of which are implemented using dedicated parametric modeling tools. Further ongoing research trends emphasize how parametric design transforms the field and creates opportunities for designers working in building energy research. The analytical results help to find current barriers, and future initiatives to implement the parametric design at a wider spread for solar integration into buildings. [Display omitted] • Analysis of parametric models for solar integration with buildings is presented. • The existing parametric models are categorized along five different categories. • Most studies developed models at single building-scale by manipulating windows. • Most models are implemented by dedicated tools for comfort and energy objectives. • The BIPV, shader, and solar façade are popular technologies for daylight and solar power. [ABSTRACT FROM AUTHOR]

The use of photovoltaic power plants is rapidly expanding, despite the continued growth in the production of traditional mineral resources. This paper analyses photovoltaic panels (PVP) in order to identify the best values of their various nominal (rated) parameters in terms of lifetime and efficiency. The authors have created a database of one-sided PVPs from 100 to 450 W power range, which includes PVPs from 72 manufacturing companies around the world. The paper analyzes 1300 mono- and polycrystalline, heterostructural and thin-film PVPs. The following PVP parameters were analyzed: efficiency, temperature coefficients of power, short circuit current, open circuit voltage, square per power, mass per power, number of cells, operating temperature and lifetime. The results obtained can be widely applied in simulating the operating modes of photovoltaic power plants and will improve the accuracy of feasibility studies of the implementation of autonomous power supply systems. • Parameters of photovoltaic panels (PVPs) is necessary for modeling and analysis of solar power systems. • The best and the median values of the main 16 parameters among 1300 PVPs were identified. • The results obtained help to quickly and visually assess a given PVP (including a new one) in relation to the existing ones. • The median and the best parameters will reduce the time of feasibility studies for the implementation of autonomous photovoltaic power plants. • According to the medians of parameters, the most efficient are heterostructural PVPs, the least efficient are thin-film PVPs. [ABSTRACT FROM AUTHOR]

Since solar energy is intermittent, finding the best solutions for solar operated devices is a challenge. Multiple techniques exist to reach the best solutions for optimal solar operated devices. A thorough review of solar energy systems' optimization methods and tools is presented in this work. The intelligent optimization techniques for solar energy systems are discussed, including their functions, constraints, contributions, mathematical models, and analysis methods. Optimization studies using new and traditional generation techniques are analyzed, and a few optimization methods, including combined hybrid algorithms, are presented. New generation artificial intelligence algorithms have been most widely used during the last decade, needing less computational time. They have good convergence and better accuracy than traditional optimization methods. They can scan local and global optima and do robust calculations. Solar system optimization has demonstrated remarkable benefits in size, load demand, and electricity output. The improvements reduce operating expenditures, power losses, and peak output integration and controllability. With a 50% rise in power prices, the optimal number of solar collectors rises by approximately 25%. However, with adjustment as per optimization techniques, the solar absorption cooling system's maximum thermal efficiency can be increased up to 75%. The present study recommends using two or more algorithms to overcome the curbs of a single algorithm. The main aim of the optimization strategies, according to this assessment, is to reduce capital expenditures, operation and maintenance expenses, and emissions while improving system reliability. The paper also briefly describes several solar energy optimization challenges and issues. Lastly, some practical future approaches for establishing a reliable and efficient solar power system are proposed for developing the complex renewable energy-based hybrid system. • A thorough review of solar energy systems' generic optimization objectives. • Background and importance of solar energy and its various applications are reviewed. • Intelligent optimization approaches for solar energy systems, including their functions, constraints, and contributions. • Optimization methods, including combined hybrid algorithms, are presented. • Practical future approaches for developing a reliable and efficient solar power system are proposed. [ABSTRACT FROM AUTHOR]

Due to the uneven distribution of renewable resources and electricity load centers in China, renewable energy usually needs to be delivered a long distance from the generation base to the load center. However, wind power and photovoltaic (PV) have to be bundled with flexible resources, such as thermal generators, to compensate for the generation uncertainty and variability. Concentrating solar power (CSP) is a controllable generation technology, and it is receiving great attention in the northwest China to be constructed in the 100% renewable energy generation base. This paper proposes a generation portfolio optimization model of a 100% renewable energy base supported by CSP. Firstly, a flexible operation model of CSP based on the interval theory is proposed. Then, a coordinated operation strategy of a 100% renewable energy base organized by CSP, wind power, PV and also energy storage is formulated. On this basis, a generation portfolio optimization model is established with the target of minimizing an extended levelized cost of energy (LCOE) considering the transmission cost. A case study of 100% renewable energy base in Qinghai Province, China, is conducted to verify the effectiveness of the proposed model. It is depicted that CSP plays an important role in the cost-effective portfolio and can be a better alternative to the combination of PV and storage. For the 100% renewable energy base in Qinghai, the LCOE with an optimal CSP, PV, wind, and storage combination is 0.5785 CNY/kWh, which is 20.3% lower than the case without the installation of a CSP station. • Building a 100% renewable energy generation base with a CSP, PV, wind, and storage combination. • A planning model with the target of minimizing an extended LCOE considering transmission cost. • A coordinated operation strategy of a 100% renewable energy base considering CSP's flexibility. • The LCOE of a 100% renewable energy base can drop 20.3% when equipped with CSP in Qinghai. [ABSTRACT FROM AUTHOR]

Smart energy transition includes a widespread deployment of clean energy technologies and intelligent energy management with information and communication technologies (ICTs). In this paper, the smart energy transition is studied from the viewpoint of the technology convergence of renewable energy sources (RESs) and ICTs. Two important, fast-growing and weather-dependent renewable energy generation technologies: wind power and solar PV (photovoltaic) are studied. This paper provides technology convergence analyses of RES and ICT inventions based on international patent data. Digitalisation is changing the whole of society, and according to the results, this transition can also be seen in the studied renewable energy generation technologies. The digitalisation of RES production covers technologies that control, manage and optimise electricity production in different intelligent ways. Differences between wind power and solar PV technologies are found: in the case of wind power, the development from virtually no ICT solutions to partial technology convergence with the ICT sector is straightforward. However, in the case of solar PV, the development of basic technologies has been even faster than the development of the solar PV ICT solutions, which may indicate the immature nature of solar PV technologies during the studied years. The digitalisation of the renewable energy sector poses challenges for RES companies in following and predicting ICT development and opportunities for innovations and collaborations with ICT companies. This conclusion can also be expanded to society and policy levels because focusing on only a narrow field when planning innovation policy instruments can negatively impact the country's competitiveness. • Digitalisation and ICT solutions are impacting on wind power and solar PV technologies. • The prominent RES technologies with ICT solutions control, manage and optimise electricity production. • Wind power patent data shows a straightforward technology convergence trend with ICT. • Basic inventions in solar PV have increased more rapidly than solar PV ICT solutions. • Digitalisation in wind power and solar PV has been driven by the US, Germany, Denmark and Japan. [ABSTRACT FROM AUTHOR]

This paper focuses on the integrated management and design of a distributed energy systems (DES) with solar generation and energy storage. The DES remains voluntary simple as the objective is to focus on the design methodologies rather than the system complexity. The article aims at bridging the gap between conventional DES design strategies, made in a single stage fashion over a representative period, and expansion planning problems that perform dynamic sizing over decades with oversimplifications of the system operations. Especially, the paper investigates to what extent the value of the model is increased when aging is controlled over the system lifetime compared to standard methods based on a single equivalent year. To address these questions, a multi-time scale model is first implemented by coupling both the DES operation and the sizing. The optimal asset capacities are computed in the form of a dynamic investment plan over the system lifetime that can accommodate potential changes in energy prices or cost of technology. Then, the results are compared with single stage design strategies on a common simulation framework. The implemented multi-time scale planning displays good performances with up to 20% cost reduction compared to typical single stage designs. Finally, the impact of the energy rates and system self-sufficiency are investigated. The obtained results show that significant investments in energy storage arise for electricity prices multiplied by three compared to the baseline or with strong self-sufficiency constraint over 60%. • Implementation of a multi-time scale model where the interaction between investment and operation is taken into account. • Introduction of a generic framework to compare and to assess the performances of different design strategies. • Comparison of the aging aware approach with more standard methods based on single equivalent years. • Sensitivity analysis with regard to different energy prices and constraint for the system self-sufficiency. [ABSTRACT FROM AUTHOR]

Globally, policies designed for high penetration of distributed photovoltaics (DPV) primarily have shifted from mainly encouraging investment through subsidies to addressing equity and stakeholder concerns on retail tariffs and utility revenue impacts. Net metering and feed-in tariffs now serve as the main policy mechanisms to support distributed PV in the U.S. and Europe, although modifications are ongoing to alleviate concerns over consumer inequity and the financial health of utilities. Retail tariff design and utility revenue impacts are now at the forefront of the debate for ASEAN countries formulating new policies and incentives for PV deployment. This paper discusses experiences of DPV development in the Philippines, Thailand, and Vietnam. These countries have ongoing efforts to adjust their DPV programs to match a rapidly dynamic and evolving DPV market and incorporate new technology capabilities such as blockchain-based peer-to-peer solar energy trading platforms. The paper also presents a quantitative analysis of customer economics under various competing compensation mechanisms and analyzes the remaining barriers to DPV market expansion in these three countries. Net billing could achieve more economically equitable policy design for other Southeast Asian countries looking to make solar electricity broadly accessible for all. • Evolving financial support mechanisms for distributed PV are reviewed in three countries. • Policy changes respond to multi-faceted factors, especially utility revenue and rate impacts. • The economics of residential and commercial customers under different compensation mechanisms are compared. • Current design of compensation mechanisms in these countries incentivize PV undersizing. [ABSTRACT FROM AUTHOR]

The European Union (EU) imports a large amount of natural gas, and the injection of renewable hydrogen (H 2) into the natural gas systems could help decarbonize the sector. The new geopolitical and energy market situation demands urgent actions in the clean energy transition and energy independence from fossil fuels. This paper aims to investigate techno-economic analysis, barriers, and constraints in the EU policies/frameworks that affect natural gas decarbonization. First, the study examines the levelized cost of hydrogen production (LCOH). The LCOH is evaluated for blue and grey hydrogen, i.e., Steam Methane Reforming (SMR) natural gas as the feedstock, with and without carbon capture, and green hydrogen (three type electrolyzers with electricity from the grid, solar, and wind) for the years 2020, 2030, and 2050. Second, the study evaluates the current policies and framework based on a SWOT (Strength, Weakness, Opportunities, and Weakness) analysis, which includes a PEST (Political, Economic, Social, and Technological) macro-economic factor assessment with a case study in Portugal. The results show that the cheapest production costs continue to be dominated by grey hydrogen (1.33 €/kg.H 2) and blue hydrogen (1.68 €/kg.H 2) in comparison to green hydrogen (4.65 €/kg.H 2 and 3.54 €/kg.H 2) from grid electricity and solar power in the PEM - Polymer Electrolyte Membrane for the year 2020, respectively. The costs are expected to decrease to 4.03 €/kg.H 2 (grid-electricity) and 2.49 €/kg.H 2 (solar – electricity) in 2030. The LCOH of the green grid-electricity and solar/wind-powered Alkaline Electrolyzer (ALK) and Solid Oxide Electrolyzer Cell (SOEC) are also expected to decrease in the time-span from 2020 to 2050. A sensitivity analysis shows that investments costs, electricity price, the efficiency of electrolyzers, and carbon tax (for SMR) could play a key role in reducing LCOH, thereby making the economic competitiveness of hydrogen production. The key barriers are costs, amendments in rules/regulations, institutions and market creation, public perception, provisions of incentives, and constraints in creating market demand. • The study evaluates the levelized cost of hydrogen production (LCOH). • LCOH of green hydrogen expected to decrease in the time-span from 2030 to 2050. • Investment costs, efficiencies, fuel and electricity prices, and carbon tax are the key variables. • We identify barriers and constraints in the decarbonization of natural gas systems. • Rules/regulations, incentives, and restructuring of market/institution are required. [ABSTRACT FROM AUTHOR]

Water-surface photovoltaics (WSPVs) represent an emerging power-generation technology utilizing idle water and solar energy. Owing to their significant advantages and development potential, the use of WSPVs has increased rapidly in recent years. Many studies have been conducted on WSPVs, and they have been assessed from different perspectives. In addition to the comprehensive characteristics of WSPVs, the adaptive utilization of WSPVs has been analyzed, as well as the influence of WSPVs on water eco-environment. In this paper, the development of WSPVs is reviewed, and the achievements related to WSPVs in the past decade are comprehensively analyzed from different viewpoints. Additionally, a new classification method for WSPVs is proposed. Furthermore, challenges and future developments of WSPVs are discussed. This review provides an understanding of the current status and development trends of WSPVs and a valuable reference for the follow-up research. • A classification method for WSPVs is proposed. • The power-generation capacity and comprehensive performance of WSPVs are analyzed. • The operation and utilization of WSPVs are investigated. • The influence of WSPVs on water eco-environment is examined. • Crucial challenges and findings related to WSPVs are discussed. [ABSTRACT FROM AUTHOR]

The paper aims to address the potential of low-carbon and renewable hydrogen in decarbonizing the European energy system; specifically, reducing emissions by 55% in 2030 compared to 1990, and targeting net-zero emissions by 2050. The methodology relies on a cost-optimization modelling approach using three models complementarily: a detailed European TIMES-type model (MIRET-EU); an aggregated model for the European energy system, allowing endogenous cost reductions based on technology deployment in a dynamic programming formulation for investment strategies (Integrate Europe); and a dedicated model for assessing hydrogen import options for Europe (HyPE). Two policy-relevant scenarios have been developed: Technology Diversification (TD) and Renewable Push (RP). Both lead to climate neutrality in Europe in 2050 but the RP scenario differs by setting new reinforced targets for renewable technologies in Europe. Results show that hydrogen production would increase sharply in the coming decades, exceeding 30 million tons (Mt) by 2030 and more than 100 Mt by 2050 in both scenarios. Polyvalence of hydrogen in decarbonizing the European energy system for certain hard-to-abate energy uses in transport and industry is also observed. European hydrogen production relies on a diverse mix including both renewable and low-carbon technologies. It is complemented by hydrogen imports from neighboring regions, that represent between 10 and 15% of total demand in 2050. Access to existing cross-border pipelines is a critical advantage compared to maritime transport. Notably, there are considerable cost reductions due to technology deployment for solar power and hydrogen production by electrolyzers. • European hydrogen demand could exceed 100 million tons per year by 2050. • 15% of H 2 needed to reach carbon neutrality could be imported from outside Europe. • More than half of H 2 is used for transport, the rest is dominated by industry. • 1800 GW of solar and wind power is needed for the roll-out of renewable hydrogen. • Resilience of natural gas in European energy transition by 2050 with uptake of CCS. [ABSTRACT FROM AUTHOR]

The use of solar thermal systems to produce heat for industrial processes is a feasible option that is gaining increasing interest in recent years as an initiative toward the zero-carbon energy future. This technology has a place in different processes, yet there is still no consensus on the main methods for sizing or controlling. The design requires the use of specific techniques due to the inconstant nature of solar energy as well as the heterogeneity of some industrial thermal demands. Nevertheless, despite starting from a particular system's design, the dynamic together with the hybrid and nonlinear behavior of the processes involved require adequate control techniques to provide the energy in a usable form and keep the system operating close to the design specifications. This paper presents a literature review concerning research works that address the design and control of solar thermal systems used in industrial contexts. The main objective is to analyze the different techniques used and to highlight their limits, usefulness, and the various industrial sectors where they were applied. The results of this analysis can be seen as a decision-making tool to select the most appropriate design or control strategy for these applications. It has been found that control techniques such as model predictive control can improve key performance metrics in daily operation. However, further development on these kinds of techniques and in holistic optimization methods that exploit the synergies between the operational and design phases is required. • Design and control methods for solar thermal systems used in industries are reviewed. • The barriers and usefulness of each technique identified are analyzed. • The analysis results in a decision-making tool to select the most appropriate method. • Optimization-based design outperforms the other techniques for heterogeneous demands. • Advanced controllers can play a role due to the nonlinear system's behavior. [ABSTRACT FROM AUTHOR]

Sudan is a sunbelt country that has abundant solar resources and large wasteland areas, especially in the northern and western portions. Concentrating solar power (CSP) technologies are proven renewable energy (RE) systems to generate electricity in neighboring countries from solar radiation and have the potential to become cost-effective in the future. Most of the attention is given to solar photovoltaic (PV) systems; no thorough techno-economic study has been carried out to evaluate the potential for CSP technologies in Sudan. The main aim of this paper is to encourage Sudan's authorities to pursue CSP technologies and overcome the associated challenges. The study used techno-economic analysis for two of the most mature CSP technologies – solar power tower (SPT) and parabolic trough (PT) technology – to produce electricity in Sudan. Two commercial CSP plants, namely GEMASOLAR and ANDASOL-1, have been "hypothetically" relocated in six Sudanese zones using the system advisor model (SAM). These zones were scrutinized based on a rigorous technical CSP site assessment study. The results indicate that the nominated zones outperformed the original Spanish plants in terms of energy outputs, capacity factors (CF), and levelized cost of energy (LCOE). The Northern state has two zones near Wadi-Halfa that are most suitable for installing CSP systems, with the SPT system offering better outcomes than the PT. This study proposes a 5 MWe SPT pilot plant with optimum specifications, enabling decision-makers to take further actions. It also recommends some actions to promote this sector and meet the 2030 and 2050 RE targets. • The CSP site assessment identified six zones for hosting CSP technologies in Sudan. • Relocating GEMASOLAR and ANDASOL-1 in Sudan showed better outputs than in Spain. • The solar power tower system is the most suitable for Sudan's environment. • The LCOE at zone1 for the 50 MWe solar tower plant is 0.086 USD/kWh. • A 5 MWe solar tower pilot plant at zone1 with optimum specifications is proposed. [ABSTRACT FROM AUTHOR]

The well-known Fresnel equations solve for the reflection and transmission of light for precise incident angles. The transmission of diffuse radiation incident on a planar or domed surface is often needed for real-world applications. Due to the complexity of the Fresnel equations, the analytical solution of the integration has hitherto been unobtainable over the last centuries. Therefore, this problem was numerically solved by integrating the angular transmittances in space often leading to substantial computing burden and bias in the results. To efficiently estimate the solar energy resource for a glass-covered photovoltaic (PV) module, we derive an analytical solution of diffuse transmission based on the rigorous integration of an alternate form of the Fresnel equations. The approach leads to a simple yet accurate relative transmittance model that reconciles the solar energy sensed by pyranometers and PV panels. With limited and clearly stated approximations, the complex mathematical derivation resulted in an elegant solution. An experiment using 1-year of data at the National Renewable Energy Laboratory's (NREL's) Solar Radiation Research Laboratory (SRRL) shows that the new model dramatically decreases the disparity between the solar radiation measurements by a Kipp and Zonen CM Pyranometer 22 (CMP22) and an IMT reference cell on a 1-axis tracking system. The solution in this paper can be widely used in scientific and engineering research, development, and applications wherever the Fresnel equations are used. • The Fresnel equations solve for transmission in precise incident angles. • This solution can efficiently reconcile the solar energy observation and the realistic energy resource for PV. [ABSTRACT FROM AUTHOR]

In recent years, freshwater reserves have been severely depleted. Demand is outpacing supply, and supply is being impacted in terms of both quantity and quality. Therefore, freshwater scarcity is regarded as one of the greatest challenges of our time. During recent decades, the concept of generating fresh water from atmospheric air has been emerging as a promising solution to overcome the global water crisis. The present review attempts to provide a novel and comprehensive classification of various AWG technologies and materials. Each technology has been summarized and discussed. Solar assisted AWG systems with a reliable and cheap energy source are thoroughly explained. Over the last few years, most AWG studies have been shifted towards hybrid/integrated systems which utilize several cooling approaches in order to increase water productivity. The present paper is primarily focused on reviewing hybrid systems with portable and round-the-clock (RTC) application capability. Performance indicators of each system; including water production and energy consumption, thermal efficiency, and coefficient of performance were evaluated and compared. Finally, possible future perspective of implementing atmospheric water generating technologies is proposed. • Atmospheric water generation techniques are classified and discussed in a new and comprehensive manner. • Hybrid atmospheric water generation systems are a great solution to increase water productivity and efficiency. • The performance and important issues of the reviewed techniques are summarized. • Portability of water production system is an important parameter in the design. • Utilizing solar energy is a good way to supply system input energy. [ABSTRACT FROM AUTHOR]

Renewable energy source (RES) based electrical power plants are widely considered green and clean due to their contribution to decarbonizing the energy sectors. It is apparent that RESs do not produce carbon dioxide, however their significant negative impacts on the environment are still found and cannot be ignored. In this paper, the environmental impacts of RES based power plants are analyzed through a comprehensive review considering solar thermal, solar photovoltaic, wind, biomass, geothermal, hydroelectric, tidal, ocean current, oceanic wave, ocean thermal, and osmotic effects. Solar thermal power is well known as concentrated solar power. A strength, weakness, opportunity, and threat (SWOT) analysis is carried out and discussed for all RES based power plants. Comparative SWOT analyses for solar photovoltaic and concentrated solar power plants are presented. The comparative environmental impact analyses for all existing RES based power plants are tabulated for various attributes. These attributes include but are not limited to human health, noise, pollution, greenhouse gas emission, ozone layer depletion, toxification, flooding, impact on inhabitants, eutrophication, dried up rivers, and deforestation. Based on the analysis, it is found that careful selection of RES for electrical power plants is necessary because improper utilization of RES could be very harmful for the environment. • A comprehensive review is presented that identifies the environmental impacts of each RES based power plants. • The detailed SWOT analysis is carried out for various RES based power plants. • The impacts along with its intensity of different water resource related RES based power plants are separately tabulated. • It is found that improper utilization of RES in power plants is harmful for the environment. • A recommended guideline is presented for the selection of appropriate RES based power plants. [ABSTRACT FROM AUTHOR]

The dynamic energy balance on the earth is jointly governed by solar energy harvesting and radiative sky cooling. Mainstream solar energy technologies, including photovoltaic conversion (PV), photothermal conversion (PT), and photovoltaic/thermal conversion (PV/T), as well as concentrated solar power (CSP) generation, have experienced significant progress after decades of developments. Recently, radiative cooling also saw significant advancements attributed to breakthroughs in material sciences and technologies. Though the energy transfer direction of solar energy collection and long-wave (above 3 μm) heat dissipation are poles apart, it is possible to combine the two mechanisms in one single system to exploit more energy from the universe. Radiative cooling has proved to be an effective way to either increase the PV efficiency by passively lowering the operating temperature of PV modules, or extend the working period of PT and PV/T collectors to nighttime and cold days via adding an extra passive cooling working mode, or enhance the thermal-to-power efficiency of CSP plants through declining the condensing temperature of the power block. This work conducts a comprehensive review and discussion on the history and recent advancements regarding the application of radiative cooling in different types of typical solar energy systems. Besides, existing challenges and possible opportunities involving combining the two ultimate renewable energy from outer space are concluded. This paper aims to provide a general summarization and possible guidance on the current status and future developments of radiative sky cooling applications in solar energy systems. • Principles of radiative cooling and four solar energy technologies are introduced. • Applications of radiative cooling in these solar energy systems are reviewed. • Some current challenges and potential applications are presented and discussed. [ABSTRACT FROM AUTHOR]

As the share of VRE (variable renewable energy) has grown rapidly, curtailment issues have arisen worldwide. This paper evaluates and compares curtailment situations in selected countries using an objective and quantitative evaluation tool named the " C-E map " (curtailment-energy share map). The C-E map is a correlation map between curtailment ratios that mean curtailed wind (or solar) energy per available energy and energy shares of wind (or solar). The C-E map can draw a historical trend curve in a given country/area, as an at-a-glance tool to enable historical and/or international comparison. The C-E map also can classify the given countries/areas into several categories, according to the current levels of curtailment ratio and historical trends. The C-E map helps institutional and objective understanding of curtailment for non-experts including policy makers. • Curtailment is one of the most important issues for wind and solar integration. • Global curtailment data in Europe, North America, China and Japan was evaluated. • Curtailment ratio does not always increase as wind and solar share increases. • Some countries/areas decreased curtailment ratio by enhancing of flexibility resource. • C-E (Curtailment - Energy Share) Map can help to grab historical trend of curtailment. [ABSTRACT FROM AUTHOR]

Renewable energy (RE) trade disputes have been rising in response to certain green industrial policies, i.e., policy mechanisms used to develop domestic RE industries and accrue associated local economic benefits. Since 2011, countries have been increasingly filing trade litigations to counter the use of green industrial policies by their trading partners so that they can expand RE industry competitiveness and the associated manufacturing jobs within their own countries. However, in the absence of systematic studies on the impacts of RE trade duties, evidence regarding their success in achieving these economic goals remains limited. In this paper, the effectiveness of RE trade duties in supporting employment, especially in manufacturing, is assessed. First, the literature on the motivations behind RE trade duties is reviewed, and then the case of trade duties imposed by the US on the imports of solar and wind energy components from China between 2011 and 2019 is examined. Although several factors may drive employment, no evidence is found for the increase in jobs in solar and wind manufacturing in the years after the trade duties were imposed. Meanwhile, downstream jobs in installation, operation and maintenance continued to grow, corresponding to increases in annual installation of solar and wind capacity in the US. These were driven by policy incentives and the declining costs of solar and wind technologies. Overall, this case study highlights the broader implication that trade duties alone are unlikely to promote local manufacturing industries, and countries would benefit from other well-designed policies. • Renewable energy (RE) related trade disputes rising but studies examining effectiveness of trade duties limited. • Literature on the goals behind trade duties on RE components reviewed. • A framework developed to assess the relationship between RE trade duties and manufacturing employment. • Framework applied to examine the case of trade duties by the US on the imports of solar and wind energy components from China. • Trade duties not effective to develop local RE industries; other well-designed policies needed to increase local RE manufacturing jobs. [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]

Integrated photovoltaics are an emerging technology which can extend the range of electric vehicles. However, up to now there is a lack of a consensus method that would provide consumers with an estimate of the fraction of annual driving which could be covered by solar power generated onboard in different usage scenarios and locations. To address this, we assess the energy implications of vehicle integrated photovoltaics for a commuter car and light delivery van for six climatic regions and for typical daily usage profiles over a ten-year period. The analysis captures the energy needs for driving and cabin temperature control to an unprecedented level of detail. Our results reveal that the grid power needed to drive such vehicles on identical routes can vary by more than 44% between climate regions. In the best case the solar power generated can cover up to 35% of the driving range per year. This contribution can vary by a factor of 2.5 between different climates, from 1800 to 5100 km annually, considerably mitigating the effect of ambient conditions on electric range. We propose developing consumer labels for solar electric vehicles that would consider this variation according to climatic conditions. The method described in this paper could help to frame initial discussions for such labels. We identify further requirements for research and development, standardisation, and policy needs. • Above 5000 km solar range possible for commuter car and van with integrated PV. • Ten year simulation reveals solar range differences by factor 2.5 across climates. • Over 44% difference in grid electricity needs across six climates globally. • At the moment vehicle integrated PV not financially viable. • Consumer labels for PVEV may be needed to inform about performance variations. [ABSTRACT FROM AUTHOR]

Integrated photovoltaics are an emerging technology which can extend the range of electric vehicles. However, up to now there is a lack of a consensus method that would provide consumers with an estimate of the fraction of annual driving which could be covered by solar power generated onboard in different usage scenarios and locations. To address this, we assess the energy implications of vehicle integrated photovoltaics for a commuter car and light delivery van for six climatic regions and for typical daily usage profiles over a ten-year period. The analysis captures the energy needs for driving and cabin temperature control to an unprecedented level of detail. Our results reveal that the grid power needed to drive such vehicles on identical routes can vary by more than 44% between climate regions. In the best case the solar power generated can cover up to 35% of the driving range per year. This contribution can vary by a factor of 2.5 between different climates, from 1800 to 5100 km annually, considerably mitigating the effect of ambient conditions on electric range. We propose developing consumer labels for solar electric vehicles that would consider this variation according to climatic conditions. The method described in this paper could help to frame initial discussions for such labels. We identify further requirements for research and development, standardisation, and policy needs. • Above 5000 km solar range possible for commuter car and van with integrated PV. • Ten year simulation reveals solar range differences by factor 2.5 across climates. • Over 44% difference in grid electricity needs across six climates globally. • At the moment vehicle integrated PV not financially viable. • Consumer labels for PVEV may be needed to inform about performance variations. [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]

Due to rapid urbanization in developing countries, it is necessary for respective governments to seek new approaches to providing sustainable fresh food and clean energy supplies. The implementation of photovoltaic (PV) systems in hydroponic farms offers an innovative solution to shortages of energy and fresh food in urban areas. These shortages have become increasingly serious during the Covid-19 lockdown periods. This paper proposes an approach to analyzing the impacts of the PV system subsidy schemes on solar-assisted hydroponic farm (SAHF) design and planning, in terms of the profit and outputs of the SAHF and the effectiveness of the subsidies. The subsidy schemes considered include the improving electricity tariff (IET), feed-in tariff (FIT) scheme, and investment co-funding (ICF) scheme. A quadratic programming model is developed to optimize the type and capacity of the PV system simultaneously. The proposed model can be solved by most commercial solvers using the linearization approach proposed in this study. A case study in Qatar is analyzed and incentive thresholds that promise PV system adoption profitability for SAHFs under IET, full FIT, surplus FIT, and ICF subsidies are identified. The thresholds are 0.0425 $/kWh, 0.0063 $/kWh, 0.027 $/kWh, and 14.90%, respectively. The subsidy conditions that lead to optimum benefits for hydroponic farmers and the government are identified via sensitivity analysis. Our method helps policymakers to optimize subsidy levels and therefore reduces subsidy inefficiency. For hydroponic farmers, it is profitable to take full advantage of the available space to enlarge their PV systems if the surplus electricity can be sold to the grid or other entities. • The design and planting decisions of the PV-enabled hydroponic farm are optimized. • A quadratic programming model is built to optimize hydroponic farm's decisions. • Various subsidy schemes for PV system are evaluated. • The minimum effective incentive levels of the subsidy policies are identified. • The profit is sensitive to surplus FIT and IET policy, while farm's outputs are not. [ABSTRACT FROM AUTHOR]

Over the past years, a new technology has emerged in the solar photovoltaics market: building-integrated photovoltaics (BIPV). Even though this technology has a lot of potential, the diffusion of BIPV has remained rather limited, globally and also in the Netherlands. In this paper, the Technological Innovation System (TIS) approach is used to analyze the historical development of the Dutch BIPV innovation system and to provide a comprehensive overview of the systemic problems that hamper further diffusion of BIPV in the Netherlands. Several systemic problems are identified, including 1) lack of policy support for the industrialization and commercialization of BIPV, 2) the absence of large firms from the construction industry resulting in the lacking industrial capacities of the BIPV innovation system, and 3) the limited value chain coordination and collaboration to help improve the compatibility and complementarity of BIPV with traditional building components and (electrical) installations. To overcome these systemic problems and enable the Dutch BIPV innovation system to move from the present niche market phase to the commercial growth phase, multiple recommendations are provided to both policymakers and value chain actors. • We use the TIS approach to analyze the Dutch BIPV innovation system. • Both the historical development and current state are considered. • Systemic problems are identified that hamper diffusion of BIPV in the Netherlands. • Policy support should promote the build-up of industrial capacities. • Value chain coordination and collaboration can improve the diffusion of BIPV. [ABSTRACT FROM AUTHOR]

Environmental and socioeconomic challenges facing many hydrocarbon-rich nations could help them evolve from hydrocarbon-based (black) into renewables-based (green) economies. In this paper, we present a case study for application of this Black Into Green (BIG) method for Iran. We show that with international cooperation Iran could indefinitely meet its energy and freshwater needs by leveraging large-scale renewable energy harvesting systems integrated with seawater pumped storage hydropower, reverse osmosis desalination, and enhanced distribution systems. This BIG transition could be facilitated by allocating a significant portion of Iran's potential hydrocarbon-based income to acquire, develop, and deploy renewable energy technology that utilizes Iran's immense solar and wind energy potential. Our analysis shows that developing just 1% of identified sites would provide over 30 TWh of annual renewable electricity generation and storage, and 221 million m 3 /day of renewably-powered desalination capacity to meet the freshwater needs of over 85% of its population. In addition to providing renewable energy design and manufacturing technology, the international community could also work with Iran to help evolve its nuclear power program toward small modular reactors for baseload power generation. Such an arrangement would contribute to regional and global security, and greatly reduce the Middle East's carbon emissions of which Iran is the largest emitter. Results from this holistic approach could then serve as a model for the world economy to work with other resource-rich nations to reduce their environmental impact while modernizing their economies and helping them achieve the socioeconomic goals outlined in the UN's Brundtland report. • Presents strategy for a sustainable economy to emerge from the COVID-19 pandemic. • Case study for Iran with oil (black) exchanged for renewables (green). • Wind and solar energy with coastal pumped storage hydro and reverse osmosis. • 1% of viable sites could supply Iran with 10% of power and 45% of freshwater needs. • Distributed economic and environmental benefits meet UN sustainable development goals. [ABSTRACT FROM AUTHOR]

Increasing energy demands and commitments in relation to climate change have accelerated the deployment of solar power globally, especially in India. Grid-connected solar capacity in the country has increased ∼11 times in just five years, from 2.6 GW in March 2014 to 28.18 GW in March 2019. However, this development has inevitably also led to the emergence of significant volumes of solar photovoltaic (PV) waste, which will only increase in the upcoming years, a considerable challenge for its waste management system. The environmental and human health risks associated with the unscientific dumping of solar PV waste have been well established in the existing literature, presenting the need to develop an effective strategy to manage this emerging waste stream. This paper presents a review of literature about India's solar PV waste management sector with a view to understanding the ground realities and identifying challenges and barriers that hinder the adoption of a regularised strategy for its management using the DPSIR framework approach. It goes on to propose a regulatory framework aimed at mainstreaming the end-of-life (EOL) management of solar PV waste in India after evaluating strategies that have already been used worldwide. In line with the Extended Producer Responsibility (EPR) concept, a multistakeholder, multi-sectoral and systematic approach has been adopted to develop a specific regulatory framework for India. The framework was subjected to a SWOT analysis to evaluate its functionality. The SWOT analysis indicates that one of the critical strengths of the framework is that it is based on a participatory approach to be adopted by all stakeholders for managing this emerging waste stream. [Display omitted] • Solar PV waste at EOL emerging as a prominent waste stream in India. • EOL solar PV waste management can foster Resource Efficiency and Circularity. • Systems approach and multistakeholder required to manage solar PV waste. • Self-standing EPR legislation is appropriate for EOL solar PV waste management. [ABSTRACT FROM AUTHOR]

Installed capacities of wind and solar power have grown rapidly over recent years, and the pool of literature on very short-term (minutes- to hours-ahead) wind and solar forecasting has grown in line with this. This paper reviews established and emerging approaches to provide an up-to-date view of the field. Knowledge transfer between wind and solar forecasting has benefited the field and is discussed, and new opportunities are identified, particularly regarding use of remote sensing technology. Forecasting methodologies and study design are compared and recommendations for high quality, reproducible results are presented. In particular, the choice of suitable benchmarks and use of sufficiently long datasets is highlighted. A case study of three distinct approaches to probabilistic wind power forecasting is presented using an open dataset. The case study provides an example of exemplary forecast evaluation, and open source code allows for its reproduction and use in future work. • Research in minutes- to hours-ahead wind and solar power forecasting is reviewed. • Knowledge transfer between wind and solar continues to benefit both fields. • An open-source case study of three distinct methods is presented. • Best practice in forecast evaluation is set out in the case study. • Common areas for improvement in research quality are identified. [ABSTRACT FROM AUTHOR]

Simulation needs to reflect reality, otherwise, it yields misleading results that are potentially harmful to the operators and decision makers who rely on that simulation. Current stochastic simulation methods for solar energy systems in smart grids mostly consider scenarios generated from a single low-frequency time series, which is unable to reflect the high-frequency fluctuation and changing uncertainty in the actual solar power output. To that end, this paper introduces a state-of-the-art probabilistic solar forecasting method, that provides remedies to the drawbacks, and thus benefits real-time stochastic simulations at large. Lasso-penalized quantile regression is paired with an analog-based preselection algorithm, and is used to forecast the irradiance over a 1 km by 1 km area, in sub-minute timescales. To capture the changing weather condition, the forecasting method uses online training, and updates its parameters and forecasts every few seconds. Despite the heavy computation required, the forecasting method is fast; it takes less than 1 s to complete a forecasting cycle. Through five benchmarking methods, ranging from the naïve climatology and persistence to the state-of-the-art analog ensemble (AnEn), the proposed method is shown to be able to attain an exceptionally high forecast skill in terms of pinball loss (up to a skill score of 55%, with AnEn being the reference model), which is unparalleled by all previous works that used the same dataset. To promote the future uptake of the method, the R code and the final forecast datasets are released on Github. • A new sub-minute probabilistic solar forecasting method is proposed. • Open-source code is released to facilitate future uptake. • The provided data can be used to simulate high-frequency fluctuations and disturbance. • Rigorous uncertainty quantification methods are used. [ABSTRACT FROM AUTHOR]

An extensive canal irrigation network in South Asia has developed over the past 170 years that consists of thousands of kilometers of constructed channels and distributaries. These canals cut across many energy-poor regions along their paths. In India, this canal network provides a unique opportunity for renewable energy generation that is yet to be realized. Existing technologies for energy generation on canals include small hydropower on canal falls and, recently, canal-top solar panels. In addition, opportunities for hydrokinetic generation in irrigation canals have received limited attention. This paper develops a novel canal-network level framework for energy planning that integrates generation with local energy needs in a canal-corridor. This framework for integrated spatial assessment analyzes the supply of renewable energy generation potential and the demand of unmet energy needs in a canal-corridor, using the Upper Ganga Canal in Uttar Pradesh, India as a case study. We consider the theoretical and technological potential of hydropower and solar power generation and develop three indices to assess the agricultural, domestic, and composite unmet power demand of the canal-corridor. Our results show an overall theoretical potential of 149.1 MW and 13,213 MW for small hydropower and solar power, respectively, which could more than help meet the current 18 hours per day electricity service standard in Uttar Pradesh. The framework uses standardized irrigation and census datasets and therefore is generalizable for canal networks across India and South Asia more broadly. • Irrigation canal energy technologies include small hydro and canal-top solar power. • Novel canal-network level framework for energy planning. • Integration of generation potential with local energy needs in a canal corridor. • Theoretical and technological potential of energy generation on canals. • Three indices for agricultural, domestic, and composite unmet power demand. [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 European power system will have to change significantly in next decades to meet the ambitious targets set by the upcoming European Climate Law. In particular, intermittent renewable energy will be increasingly injected in the system creating potential stability problems. Already in the last five years it has become evident that if the grid expansion does not keep pace with increasing demand for transmission capacity, congestion will happen more and more often in the European power network. To handle congestion, Transmission System Operators extensively use redispatching, requiring individual plants to alter their market-based functioning pattern in order to cope with technical limitations of the network. While the cost of redispatching actions is well known, the change in emission patterns of both greenhouse gases and air pollutants caused by these actions is not, mostly because of a lack of detailed publicly available data. This paper covers such a gap taking Germany as a case study, thanks to the quality of the available data. Following the standard methodology for estimating the direct emissions from fossil fuelled and renewable fed power plants, the study estimates the changes in the emissions of four regulated air pollutants (namely NO x , SO 2 , Particulate Matter and CO) together with those of CO 2 related to redispatching, for the years 2015–2019. The case study of Germany shows how the management of congestions through redispatching does not necessarily imply an increase in the emissions associated with power production in a country, although it has not been possible to complete the study with a full picture of the consequences for other countries emissions because of lack of consistent data. • Power redispatching in Germany in 2015–2019 did not increase GHG and air pollutants emissions. • The impact of redispatching on emissions from neighbouring countries has not been assessed because of lack of data. • Curtailment of wind and solar power is increasing: Opportunities for further potential emissions reductions are lost. • Congestion in the power network remains an issue in Europe. [ABSTRACT FROM AUTHOR]

The particle solar receivers (PSRs) have attracted widespread attention because of their high-temperature absorption and thermal energy storage functions. Among varieties of receivers, fluidized bed particle solar receivers (FB-PSRs), which based upon gas-solid fluidized bed technologies, have excellent heat transfer performance and high thermal efficiency. FB-PSRs provide new opportunities for the development of next-generation concentrated solar power (CSP) stations. As a good reactor, FB-PSRs can also be applied in the concentrated solar thermochemistry industry such as particulate reactive process, water splitting, calcination and so on. In this paper, different types of FB-PSRs for concentrated solar applications have been comprehensively reviewed, including upflow bubbling fluidized bed solar receiver, linear particle solar receiver, countercurrent fluidized bed particle receiver, autothermal fluidized bed solar receiver and solar air receiver based on particle heat collection. Furthermore, both the merits, limitations and applications of different FB-PSRs are discussed. As one of the most mature technology, the feasibility of the upflow bubbling fluidized bed solar receiver is proved by on-sun testing with outlet particle temperature exceeding 750 °C and high wall-to-bed HTC exceeding 1000 W/m2∙K, and may have the potential to drive a megawatt-scale CSP plant when the problem of slugs solved. The properties of particles affect the FB-PSR performance and particles need to be properly selected. Moreover, the research methodology that refers to FB-PSRs is summarized. This review thus serves as a useful reference for the design and research of high-temperature particle solar receivers based on gas-solid fluidized technologies. • Provides an up-to-date comprehensive overview of particle receivers/reactors based on fluidized bed technology. • Reviews and discusses previous progress on materials' selection principles. • Analyses the research status and characteristics of particle receivers/reactors. • Assesses merits, constraints, applications, and prospects of particle receivers/reactors. • Summarizes research methods of gas-solid fluidized bed technology applied in CSP. [ABSTRACT FROM AUTHOR]

The paper's objective is to quantify factors influencing a rural homeowner's decision to invest in exterior insulation to improve energy efficiency, lower heating costs, decrease air pollution, and reduce ash disposal and time spent monitoring coal-burning stoves. The study estimates a probit decision equation using survey data collected from an area lagging in economic development and calculates decision probability change in response to a variety of homeowner characteristics, perceived importance of issues related to energy efficiency, and location. The resulting calculation of probability changes on choosing to invest in external insulation show that respondents with higher education had a 6.4% higher probability of making the decision to invest in insulation, but the probability decreased by 11.2% for every additional person added to the household. Residents with the lowest incomes had a relatively higher probability to insulate a house than those with more income, but being a farmer decreased the probability by 60.7%. Energy-saving attitudes reflected in recent purchase of energy-efficient household appliances had a 41.2% higher probability to choose exterior insulation. Favoring to pay more for locally-generated solar energy increased the probability of investing in exterior insulation by 16.2%, while those who wanted the hot water supply independent from electricity had a 24.2% higher probability. The quantified effects facilitate targeting rural households and increasing their participation in recently introduced programs aimed at energy-efficiency. • Rural families living in older homes gain from energy saving exterior wall insulation. • Investing in exterior insulation 11.2% less probable in large households. • Buying new home appliances increases probability of exterior wall insulation. • Residents supporting renewable energy more likely to insulate exterior walls. • Farming households less likely to insulate exterior walls than non-farm households. [ABSTRACT FROM AUTHOR]

With a growing population, lack of balance between water demand and traditional freshwater supply has become a critical issue. A solar still is a simple, impactful device for producing freshwater from alternative water sources such as brackish water, wastewater, and brine by sole or partial consumption of solar energy. Solar stills are highly suited for the water-stressed regions with limited access to electricity but abundant solar energy, or places with no sustainable and affordable options for clean water. Owing to these advantages, fundamental and applied research related to solar stills has been of interest to the water industry. The main shortcoming of solar stills is the low freshwater productivity, and thus the research focus in the field has been to improve their productivity. Existing review articles on solar stills presented their classification based mostly on the structural designs and add-ons for boosting the freshwater production rate. However, a solar still is fundamentally a system involving thermal processes. Therefore, this overview, for the first time, presents the classification of the solar stills from the perspective of the basic thermal processes involved and the associated enhancement techniques pursued for each of these processes. The advantage of this review is that it will enable to systematically understand the role and impact of each thermal process on the freshwater production rate, thereby enabling a pathway for the future researchers to focus on developing solutions from a perspective of reducing the largest thermal resistances. In addition, the present paper reviewed the recent developments in interfacial-evaporation-based enhancements for solar stills, which was not covered in the existing reviews. • Solar still enhancements are reviewed from a new perspective of thermal processes. • Enhanced solar stills have potential to be competitive. • Solar input followed by heat storage and evaporation processes impact productivity. • Combination of enhancements was also found to improve productivity. • Future enhancement needs are identified. [ABSTRACT FROM AUTHOR]

Along with the increasing rate of using renewable energies, following the finite amount of fossil fuel resources, and the associated pollution of these non-renewable energies, photovoltaic systems have recently achieved widespread acceptance to harness solar energy in the last decades. Since photovoltaic systems have a limited lifespan and cannot be used after a while, it seems imperative to pay attention to recycling and sustainability in the supply chain network design of these systems. In this respect, this paper first reviews the photovoltaic systems literature systematically. Thereinafter, a multi-objective, mixed-integer non-linear optimization model is deployed to design a photovoltaic supply chain network addressing the system's associated costs, environmental impacts, and social values. The concerned model also considers a reverse flow in addition to the typical forward flow in the proposed supply chain for special environmental and social issues. Likewise, to optimize the presented multi-objective model, the augmented ε-constraint method is employed, being capable of warranting the Pareto optimal solutions. Eventually, the model's efficiency is illustrated by discussing a real-world case in Iran, through which prominent managerial results are acquired. • The photovoltaic systems literature is systematically reviewed. • A multi-objective, mixed-integer non-linear programming model is proposed to design a sustainable photovoltaic supply chain network. • The concerned model is able to consider a reverse flow in addition to the typical forward flow in the proposed supply chain. • To solve the proposed multi-objective model, the augmented ε-constraint method is deployed. • The efficiency of the model is illustrated by discussing a real-world case in Iran. [ABSTRACT FROM AUTHOR]

The organic Rankine cycle (ORC) is an effective technology for power generation from temperatures of up to 400 °C and for capacities of up to 10 MW el. The use of solar irradiation for driving an ORC is a promising renewable energy-based technology due to the high compatibility between the operating temperatures of solar thermal collector technologies and the temperature needs of the cycle. The objective of this review paper is to present and discuss the operation principles of solar-ORC technology and the wide range of solar-ORC systems that have been studied in the literature. Various solar thermal technologies that can drive the ORC are investigated, such as the flat plate collector, evacuated tube collector, compound parabolic collector, parabolic trough collector, linear Fresnel reflectors, dish concentrators and solar towers. Both simulation studies and experimental investigations are included in the study. Hybrid systems and different thermal storage techniques are also examined in detail. Moreover, systems with ORC which produce many useful outputs such as cooling, heating and fresh water are studied because they present high sustainability indexes. The limitations of the technology are also highlighted, along with critical suggestions aimed at steering future research in this field. The final conclusions indicate that the development of trigeneration and polygeneration systems with ORC sub-systems is a promising avenue, not only for the future development of solar-ORC technology but also for the development of renewable and sustainable energy systems in a broader context. • Solar driven organic Rankine cycles are summarized and discussed in detail. • Concentrating and non-concentrating solar thermal systems are included. • Parabolic trough collector is the best solar technology for power production. • The use of solar organic Rankine cycles in polygeneration is a promising idea. • There is a need for conducting future experimental studies in a great scale. [ABSTRACT FROM AUTHOR]

A photovoltaic/thermal (PV/T) technology, producing electricity and heat simultaneously, has attracted extensive attention. Integration of phase change materials (PCMs) into PV/T systems as auxiliary cooling media or/and heat storage media to improve the system performances has been prevalent in recent years. This paper aims to critically and comprehensively review the research progress concerning utilization of PCMs in PV/T systems. The adopted performance evaluation indexes and applied PCMs in various PV/T systems are gathered and analysed. The configurations and effects of bulk PCMs in standalone PV/T modules, building-integrated PV/T systems and PV/T systems integrated with other energy conversion technologies are elaborated with special attention paid to the microencapsulated PCM (MPCM) slurry applied in PV/T modules. The effects of thermophysical properties and mass of PCM/MPCM, operation parameters of working fluids, and environmental conditions are also discussed, whilst heat transfer enhancement approaches for PV/T-PCM modules are explored. It has been identified that the integration of PCMs can effectively elevate the system performances when the phase change temperature and operation parameters are carefully tailored according to environmental conditions. Finally, research prospects and opportunities are proposed in terms of material fabrication and modification, system integration, model development as well as performance analysis. The review can provide crucial references for high-efficiency PV/T-PCM system design and further development of relevant technologies. • PCMs adopted in PV/T systems as well as the system performances are summarized. • Configurations and roles of bulk or microencapsulated PCMs in PV/T are elaborated. • Effects of key parameters on PV/T performance with PCMs are comprehensively analysed. • Use of PCMs in building-integrated PV/T helps to flexibly adjust spatial energy flow. • PV/T with PCMs can be flexibly integrated with other energy conversion methods. [ABSTRACT FROM AUTHOR]

The future of climate-resilient energy systems relies on the transition to incorporate renewable energy with energy storage, such as solar energy. Solar thermal provides desirable thermal energy (heat) for industry, commercial, and residential sectors. Significant attempts have been made to improve the design and its integrated systems, thus reducing the costs and making the technology more competitive for industrial applications. This paper evaluates the solar thermal potential and the economic feasibility standard of the technology from low-temperature heat demand up to 100 °C by focusing on the food industry. Throughout this review, theoretical concepts, design types, and recent developments related to this sector's integration systems are explored. This study also highlights the integrated systems gap and emphasises the assessment of integration points and the range of operating temperature. This review aims to assist industries in the food processing sector to keep them abreast with the latest solar technology developments for the food industry. Up to 2020, at least 95 solar thermal plants with a total capacity of 41 MWth had been installed globally for the food industry. The flat plate collectors were the most applied solar collectors in the food industry, represented by 38%. It has been shown that the most common heat applications are pre-heating, cleaning and pasteurisation. The configuration and design of the integration framework for this sector rely primarily on each application's specific features and nature of the process. Based on the installed solar thermal plant, 27% was used for heating of make-up water. • Solar thermal applications in food industries. • Quality and quantity of low-temperature heat demand for the food industry. • Solar thermal integration concept with the existing industrial processes. [ABSTRACT FROM AUTHOR]

This paper reports experimental work related to passively cooled free-standing silicon photovoltaic panels (PV) in different cooling configurations with a considered utilization of phase change materials (PCM). The PV panels (20Wp) were examined in typical Mediterranean climate conditions during several months of field monitoring. The focus of the research was to reconsider the usually conventional applied passive cooling approach for PVs in cases when the PV panel is cooled with phase-change materials (PV-PCM cooling systems). The conventional approach usually assumes one solid container filled with a PCM that is fixed into the backside surface of the PV panel to regulate the operating temperature of the PV panel. In the herein considered novel approach, instead of one PCM filled container, several smaller containers filled with PCM materials were used and experimentally tested to determine the performance benefit. The gained experimental results of the two different PV-PCM cooling configurations were compared with a referent PV panel. Based on the experimental results, it was found that the performance of the PV system (overall power yield), for the assumed measurement period, was improved for about 2.5% in the case of the concept with a full PCM container when compared to the referent PV panel. The proposed novel PV-PCM passive cooling approach, with several independent PCM containers, reached a performance improvement of 10.7%, which is considerably higher with respect to the usually applied concept with a full PCM container. The quantity of utilized PCM materials and aluminum, in several container configurations, was 47% (PCM) and 36% (aluminum) less, when compared with the passive cooling configuration with solid a PCM container. The revealed results indicated the potential of the novel proposed PV-PCM passive cooling approach regarding performance improvements and resource utilization, which would affect both economic and environmental aspects. • Two passive cooling configurations experimentally examined for photovoltaics. • Passive techniques considered the use of a phase change material (PCM). • Novel PV-PCM cooling approach tested. • Highest performance improvement of 10.7% ensured by the novel approach. • Reduction of main resource use by 47% (PCM) and 36% (aluminum). [ABSTRACT FROM AUTHOR]

Solar and wind energy are expected to play a key role in creating a climate-neutral Europe by 2050 and decarbonizing energy production in general, albeit requiring significant deployment. This presupposes that the population accepts such energy sources, thus necessitates understanding how people perceive energy systems. Unlike the abundant literature about wind energy, social acceptance of solar energy has received less attention, especially concerning large solar installations. Opinion polls indicate that solar energy enjoys a high level of socio-political acceptance and is preferred to other renewables, although it is unclear whether this acceptance persists as the technology is deployed on a large scale. This paper helps close this gap by describing the results of a representative survey (n = 601) conducted using a between-subject design to examine how attitudes of the public towards solar energy vary based on the size of installations, how the latter compare to attitudes towards wind energy, and what the role of affect is in the former. Results reveal that the stronger preference for solar power decreases to a similar level as that for wind energy when comparing installation of similar sizes, highlighting that solar energy installations may not easily be scaled up. The study also shows that affect plays an important role in forming people's attitudes towards wind and solar, especially concerning large-scale installations. This underlines the need for policymakers and project developers, who aim to deploy renewables on a large scale, to attend to the affective component of decision-making. • Between-subject design survey with a representative sample (n = 601). • Positive attitudes towards solar energy are mediated by installation size. • Solar parks are less positively perceived than rooftop PV installations. • When comparing installations of similar sizes, solar is not more popular than wind energy. • Large installations evoke stronger emotions, which in turn influence attitudes. [ABSTRACT FROM AUTHOR]

The global shipping industry faces huge pressure to reduce its greenhouse (GHG) emissions due to the International Maritime Organization (IMO) has introduced strict regulations to decrease GHG emissions from ships. New energy sources can provide a solution for green shipping because they have the advantages of abundant, renewable and clean. This paper examines the current progress made regarding the integration of new energy sources into conventional ship power systems, including solar energy, wind energy and fuel cells. It also discusses the possibilities for using the aforementioned three new energy sources in ship power systems ranging from technical principles to subsequent applications. Furthermore, basic working theories of new energy sources, application methods, existing new energy ships and core technologies required are summarized in detail. The integration of new energy sources into traditional ship power systems has enormous potential to bring the shipping industry in line with international regulatory requirements and is set to become a key focus of ship-related researches in the immediate future. [ABSTRACT FROM AUTHOR]