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The present paper reviews the green hydrogen uptake policies in the United States and the European Union. While the EU has a rather broad public support strategy that envisages the entire hydrogen value chain, the U.S. policies are more focused on hydrogen research hubs and subsidies having electric vehicle applications. From the experience of the solar and wind power rollout of the past three decades, we know that the subsidization schemes of the end product play an important role in the transition to renewables. These kinds of subsidization schemes are still lacking for clean hydrogen both in the EU and the U.S. This paper provides a brief overview of selected subsidization schemes from other renewables markets, which are then applied to define an exemplary subsidization path to empower large-scale growth in a market for green hydrogen. Here is proposed a long-term subsidization scheme – deemed as an adequate strategy for the expansion of clean hydrogen in an electricity mix. The suggested exemplary subsidization path recommends shifting from feed-in tariffs to direct marketing with market premiums once a certain threshold is reached, while both can be flanked by the issuance of a Guarantee of Origin for green hydrogen so that there is one market for hydrogen and another market for the certificates. • -A long-term subsidization scheme for the rollout of green hydrogen in the electricity mixes is proposed. • -An exemplary subsidization path to empower large-scale growth in a market for green hydrogen is drafted. • -U.S. and EU are used as case studies to capture lessons for subsidization of green hydrogen economy uptake. • -The U.S. has more centralized green hydrogen rollout policies, whereas the EU has a wider policy toolkit. • -Shifting from FIT to direct marketing with market premiums is key once a certain pre-defined threshold is reached. [ABSTRACT FROM AUTHOR]

• A new Free-Drift Solar Power Satellite concept is proposed. • Large amount of fuel is saved because of the free-drift orbit and attitude. • Symmetric layout is adopted to reduce attitude disturbance. • Two transmitting antennas are used to reduce the total length of cables. Solar power satellite is known as a promising source of clean energy from space in the future. One of the key problems of current solar power satellite concepts is the huge cost because of the excessively large mass and fuel consumption. The objective of this paper is to propose a new Free-Drift Solar Power Satellite concept that reduce mass and fuel consumption. Firstly, Sun-frozen orbit in geosynchronous Laplace plane and quasi-Sun-pointing attitude are designed to significantly save orbital and attitude control fuel. To this end, an orbit-attitude coupled modelling method considering space perturbations is proposed for multibody systems. Orbital and attitude dynamics and control are studied to substantiate the orbit and attitude design. Secondly, two transmitting antennas and three solar arrays are adopted and allocated elaborately to reduce structural deformations and attitude disturbance. The mass of the transmitting cables from solar arrays to transmitting antennas is also reduced by the proposed layout. Finite element analysis is performed to validate the design of supporting structures. Finally, other subsystems are briefly introduced and the system parameters are summarized. [ABSTRACT FROM AUTHOR]

Constructing an accurate and reliable solar photovoltaic (PV) power forecasting system is crucial for smart grid management and dispatch. However, due to the intermittent, non-stationary and random nature of solar energy, current methods cannot effectively capture the dynamic change patterns of PV data, resulting in a forecasting accuracy that cannot satisfy the requirement for stable operation of smart grids. To address this issue, in this paper, a new solar PV power forecasting system is proposed based on a new adaptive mode decomposition method that combines machine learning models. First an adaptive mode decomposition method is proposed for adaptively eliminating high-frequency information of PV data, mitigating the impact of high noise on the forecasting performance. Then the powerful mapping ability of machine learning model is utilized to construct a solar PV power generation combination forecasting system. The system adopts a multi-objective optimization strategy to determine the optimal weights of the combination model, which reduces the volatility of the forecasting results and enhances the stability of the forecasting system. Experimental results demonstrate that the proposed system achieves the best overall performance with online manner on 10 state-of-the-art baselines. Furthermore, the evaluation analysis by Diebold–Mariano test, improvement ratio and sensitivity analysis further show that the stability and accuracy of the proposed system outperforms the comparative baselines. [ABSTRACT FROM AUTHOR]

• A multi-microgrid energy real-time optimal control scheduling strategy is proposed. • Energy storage devices can actively participate in optimal energy scheduling. • Improved resilience and flexibility of energy dispatch for multiple microgrid. • Significantly reduce the number of microgrid connections to the distribution grid. • Maximising the full uptake of renewable energy in multi-microgrid systems. With the increasing prominence of the energy crisis and global climate issues, it has become an important cornerstone of the energy revolution to improve the utilization rate of renewable energy and gradually reduce the use of fossil energy. Nonetheless, the erratic fluctuations and instability of renewable energy sources such as wind and solar energy have presented certain obstacles to the effective utilization of renewable energy. In order to maximize the utilization of renewable energy, enhance its utilization efficiency, and reduce the carbon emission of power supply, this paper first proposes a real-time collaborative optimal energy scheduling and dispatching control model for multi-microgrids. Subsequently, it proposes a real-time optimal control and dispatching strategy for multi-microgrid energy based on storage collaborative. This model considers the energy storage device as an energy management controller, enabling it to participate in the energy collaborative dispatch of multi-microgrid. This enables the energy storage device in the microgrid not only to actively participate in the optimal scheduling of energy, but also to make the energy in the storage device be reasonably distributed in the multi-microgrid system, to maximize the full absorption of renewable energy in the multi-microgrid, thereby reducing the dependence of the microgrid on the distribution network, and significantly improving the elasticity and reliability of the multi-microgrid system. Finally, the feasibility and effectiveness of the proposed optimal control scheduling strategy are verified by simulation. [ABSTRACT FROM AUTHOR]

Accurate photovoltaic (PV) power generation forecasting is crucial for optimizing the integration of solar energy into power grids and advancing towards a cleaner, more sustainable energy future. However, the inherent variability and complexity of PV power generation data pose significant challenges for accurate forecasting. To address these challenges, this paper introduces Collaborative Directional Representation (CoDR), a novel deep learning model that extracts and represents the directional fluctuations of solar irradiance data to improve forecasting accuracy and reliability. CoDR utilizes a series of steps, including data preprocessing, fluctuation extraction, directional representation, linearization, de-extraction, mapping, and data postprocessing, to capture both the temporal and spatial dependencies within the data. CoDR leverages a unique directional representation to capture both temporal and spatial dependencies in the data, enabling superior forecasting accuracy and robustness compared to twenty-two state-of-the-art benchmark methods. We validate CoDR on a real-world dataset of PV power generation in Belgium, demonstrating its effectiveness through extensive experiments, ablation studies, and sensitivity analyses. Importantly, CoDR enhances the transparency of the forecasting process by revealing the causal relationships and directional influences among input variables and PV power output. This explainability feature provides valuable insights into the underlying drivers of PV power generation, promoting trust and informed decision-making in the transition to cleaner energy systems. • Introduces Collaborative Directional Representation (CoDR) for accurate PV forecasting. • Outperforms 22 benchmark methods, achieving significant error reductions. • Provides explainable insights into PV power generation using 3D visualizations. • Demonstrates effectiveness on a real-world Belgian dataset through extensive analyses. [ABSTRACT FROM AUTHOR]

Solar thermal energy is one of the important sources of renewable energy. The solar thermal energy gives clean energy which can be utilized for industrial applications. Industrial heaters which require heat energy for many industrial uses can be attained using these solar thermal absorbers. The solar thermal absorber is designed using a layer design that consists of material compositions of Titanium (Ti) and Stannic selenide (SnSe 2) for ground and substrate sections respectively. A graphene layer which has the good properties to be used in solar absorbers is added between the Aluminum and SnSe 2 material. A thin graphene section is inserted above the SnSe 2 substrate and below the Ti resonator. To catch the good absorption in the current design, the best four wavelengths (micrometer) have been attached such as 0.22, 0.8, 2.46, and 2.85. This design's contribution can be studied in 4-atm regimes (from UV, V to NIR, and MIR). According to the wavelength and bandwidth ranges, the current absorption explores more than 97% (97.4%) in between 2.4 and 3 μm (600 nm) bandwidth and exceeds 95% (95.2%) from 0.2 to 1 μm (800 nm) respectively. To the overall range of design, it extracts 90.3% for the 2800 nm band between 0.2 and 3 wavelength regime. The flow of the presentation of the proposed paper is (i) Introduction (ii) Design and Parameters, and (iii) Results and Discussions. The explored absorber can be effective in water heating and swimming pool heating for homes. Moreover, it can also be applied in large industries as a solar thermal absorber for heating applications. [ABSTRACT FROM AUTHOR]

Abstract Despite a significant progress in electrification over the last decade, more than 1 billion people have no access to electricity, and about 3 billion use solid fuel or kerosene for cooking and heating purposes. More than 95 % of them live in sub-Saharan Africa or developing Asia, and around 80 % are situated in rural areas. Conventional approach to power supply such as transmission grid extension is not economical due to high investment and connection costs. Technological progress has shifted down capital costs of renewable off-grid solutions. However, in the most cases, it is not enough to reach feasibility of these solutions due to weak investment conditions and weak purchasing power of the local population in these areas. The choice of business model can have a vital role in bringing electrification and connectivity to rural areas, providing flexibility and adaptability of the technology to the market conditions. Analysis of existing literature on business models for off-grid solutions concludes that the model for rural areas in developing countries should be more service oriented, be scalable to various use case scenarios, should provide good risk balance between customer and provider, and should enable transparency and quality of service. This paper analyses recent developments in off-grid system solutions for sub-Saharan Africa and provides classification of business model innovations. Based on the analysis, the paper proposes an innovative business model for Fusion Grid project, scalable mini-grid integrated with connectivity solution. Feasibility of the project is tested for three different cases, depending on the type of the rural community. Results suggests that combining micro-grid based power supply and internet connection as one service can contribute to a viability of the project, and, furthermore, can contribute to achieving global electrification goal. [ABSTRACT FROM AUTHOR]

Abstract Climate change and global warming are currently the biggest threat to human society. In Iranian households, buildings expend 33% of the yearly energy consumption. The potential of renewable energy sources in Iran is high and Iranian government is taking steps to increase the use of renewable energy sources. This paper examines the use of renewable energy in two major city buildings in Iran. In this paper, solar radiation in two cities (Tehran and Yazd) is analysed. The average annual sum of solar irradiation in Yazd is 2200 kWh/m2 and in Tehran, the amount is 2000 kWh/m2 [1]. The major task in this paper is to quantify the impact of geographical region and to evaluate the viability of implementing renewable systems in buildings in Iran. To reach this end, the annual average solar radiation is calculated in each city. Hourly Analysis Program is used to design each building and calculate their respective heating and cooling loads. Photovoltaic solar systems and solar-thermal systems are designed for both of the buildings. It is seen that, although Yazd has hot and arid climate compared to Tehran, the cooling and heating load in the building in Tehran is higher, and the higher solar radiation in Yazd reduces the number of solar panels required for the designed building. However, the difference is not significant. It is assessed that in order to have more efficient systems, the grid infrastructure in Iran should be upgraded to enable applying large-scale renewable energy systems for buildings in a neighbourhood. [ABSTRACT FROM AUTHOR]

Abstract This paper analyzes the framing of community in community solar projects from a geographic perspective. Through an extensive literature review of academic articles, policy documents and research theses, along with analysis of web-based literature from solar developers, utilities, goverment and non-government agencies, this paper provides a critical perspective for enhancing limited research of an emerging community energy framework. We argue the concept of community has not been adequately defined in relation to community solar. Consequently, the concept of community has been misrepresentated through what we define as 'community washing'. [ABSTRACT FROM AUTHOR]

There is abundant solar potential in the Middle East North Africa region. Yet access to sustainable energy is still a fundamental challenge in many countries of this region. In this paper we seek to understand the success and failure of the development and the diffusion of solar energy technologies by analysing using a Strategic Niche Management framework to compare the niche development of solar thermal energy and solar photovoltaics in Lebanon. This paper has two main questions: (1) How have the solar thermal niche and the solar photovoltaic niche developed in Lebanon, and how do they compare? (2) In which ways does the Strategic Niche Management framework help us to understand the development of solar energy niches in a developing country context? To answer these questions, a cross case analysis of solar thermal and solar photovoltaic systems was conducted. Due to the absence of research using Strategic Niche Management in Middle Eastern developing countries, this study uses an illustrative case from a country in this region to contribute new insights. Moreover, unlike the Strategic Niche Management research that only focuses on single case studies, this paper presents the results of a comparative study of two niches. The main Strategic Niche Management propositions were grouped and compared per item (i.e. on voicing and shaping expectations, social networks, and learning). The results show that the solar thermal niche affected the solar photovoltaic niche to a large extent. This was especially in relation to the learning and coordination processes. This has gradually contributed to establishing a clear vision. However, both niches lacked a niche manager who was able to coordinate, manage and maintain the dynamics of the niche processes. It also lacked horizontal collaboration between key actors involved (i.e. ministries). International donors were found to play a crucial role in initiating and shaping the market with certain constraints of prioritization in the region. The paper ends with conclusions and ideas for future research on solar energy niche development in the context of developing countries. [ABSTRACT FROM AUTHOR]

Water is an essential commodity for society, and alternate resources such as seawater and wastewater are vital for the future. There are various desalination technologies that can provide sufficient and sustainable water sources. Renewable energy-based desalination technologies like solar-based interfacial evaporation are very efficient and sustainable desalination methods. Solar-based interfacial evaporation has been a focus due to its efficient and easy-to-use methods. Still, research is needed for fouling resistance, scalable and low-cost materials, and devices for solar interfacial evaporation. Recent research focuses on the materials for evaporation devices, but various other aspects of device design and fabrication methods are also necessary to improve device performance. In this article, all the evaporator device configurations and strategies for efficient evaporator devices are compiled and summarized. The evaporator devices have been classified into eight main categories: monolayer, bilayer, tree-like design, low-temperature designs, 3D-Origami-based designs, latent heat recovery design, design with storage/batch process, and contactless design. It was found that a good absorber, well-engineered air-water interface, and bottom-layer insulation are necessary for the best systems. The current research focuses on the vapor production output of the devices but not on the water production from devices. So, the focus on device-based water production and the associated cost of the water produced is essential. This article articulates the strategies and various scalable and efficient devices for evaporation-based solar-driven desalination. This article will be helpful for the researchers in improving devices output and coming up with a sustainable desalination and water treatment. [Display omitted] • The paper discusses the outlook and challenges for Solar driven interfacial evaporation devices. • The article lays the path for efficiency improvement for interfacial evaporation Devices. • Floatable devices with tree-like designs have better performance. • The absorber and condenser designs are equally essential for ISDE water production devices. [ABSTRACT FROM AUTHOR]

• Green hydrogen generation devices were studied. • Methods for annual operation evaluation were proposed. • Experimental study on transient states was conducted. • Case study for 10 MW renewable energy plant was considered. This study presents a comprehensive methodology to evaluate plants that integrate renewable energy sources and hydrogen generation devices. The paper focuses on presenting the methods for devices' operation assessment taking into account the annual operation. Multiple effectiveness indices have been presented. On the basis of experimental investigation with the hydrogen generator, the methods for assessing its operation during start-up phase and sudden change in the supply current were proposed. The results of the experiments and the provided mathematical models show that dynamics of the hydrogen generator should be taken into account when selecting the suitable device for cooperation with variable renewable energy. It is especially important for multiple start-ups throughout the day due to significant differences in the amount of hydrogen produced by devices characterized by the same efficiency, yet various time constants. Methodology for selecting the optimal nominal power for hydrogen generator to cooperate with given renewable sources was developed. It was proven the optimal power depends on the type of the renewable source and minimal load of the hydrogen generator. Several case studies, including the integration of wind and solar energy farms to yield a 10 MW renewable energy farm were considered and the minimal load of the hydrogen generator impacts the annual operation of the device has been presented. The paper provides a set of tools to contribute to the development of sustainable energy plants. The methods proposed in this paper are universal and can be used for various renewable energy sources. [ABSTRACT FROM AUTHOR]

The rapidly growing state of energy consumption and the urgency of mitigating the harmful effects of climate change have accelerated our transition to renewable energy. This paper proposes a multi-level framework for exploring the global competition to develop renewable energy technologies. Through a combination of text mining techniques and by analyzing a corpus of patents covering six renewable energy technologies from 1970 to 2019, we reveal the lifecycle of these technologies, the original sources of these technologies, their potential markets, and the different supply and demand patterns of the major countries/regions involved. The results show that solar and wind energy are currently the most widely used renewable energy sources, yet biomass is the only energy source still in its growing stage. China's patents have seen a rapid upward trend, spurred on by strong policy promotion, which runs counter to the decrease in patent applications seen in most other major countries in this area. However, China's technology imports still far outweigh its exports, indicating that there is still a sizeable gap between China and some of the more developed countries like the United States, Germany, France, and the United Kingdom in terms of high-quality, high-value patents. Accordingly, China, the United States, and Japan are currently the leading in the world's renewable energy markets. That said, the market potential of Europe, Canada, and Australia should not be underestimated. These and more themes are discussed from a political, economic, environmental, and global governance perspective. This paper provides useful insights into the global renewable energy technology landscape, particularly the competitive dynamics at play. The aim is to guide policy makers or managers on the next steps in our progress toward applying and using renewable energy at scale. [ABSTRACT FROM AUTHOR]

Solar energy is one of the widely used renewable energy that can be harnessed either by directly deriving energy from sunlight or indirectly. Solar water heating system, on the other hand, is one of the applications of solar energy that has drawn great attention among researchers in this field. Solar collectors, storage tanks and heat transfer fluids are the three core components in solar water heater applications, which are reviewed in this paper. This paper discusses the latest developments and advancement of a solar water heater based on the three basic components that may affect the thermal performance of the system. It also reviews the development of various types of solar collectors in solar water heater, including both the non-concentrating collectors (flat plate collector, evacuated tube collector) and the concentrating collectors (parabolic dish reflector, parabolic trough collector). All these are studied in terms of optical optimization, heat loss reduction, heat recuperation enhancement and different sun tracking mechanisms. Among the non-concentrating and concentrating collectors, the parabolic dish reflector collectors show the best overall performance. The use of nanofluids as a heat transfer fluid was also discovered in this paper. [ABSTRACT FROM AUTHOR]

Renewable energy in Middle East and North Africa (MENA) region, particular solar energy, can be connected to Europe to provide the Northern neighbouring countries with electricity. To achieve this long term objective, it is necessary to understand the local domestic consumption of electricity in the MENA region as the main consumer of energy. The understanding of current and future trends could help to provide a complete picture of the energy situation in MENA region and the feasibility of exporting energy to Europe. For this reason, this paper investigates the domestic energy use and occupants’ energy behaviour in Libya. The aim of this study is to evaluate the effect of domestic energy consumption and householders’ awareness, attitudes and behaviour on the overall energy consumption in Libya and how this could affect the peak demand, capacity, future trends and government energy budget. The paper also investigates the sustainability aspect of consumer products and the awareness and attitude of consumers towards consumption and demand. A comprehensive survey has been conducted to evaluate several aspects of domestic energy demand and characteristics in Libya. The findings have indicated that there is a significant increase in energy demands in the household sector in Libya and it is significant to have a clear strategy to reduce carbon emission and energy use by improving occupants’ behaviour as well as utilising other sustainable measures. Minor adjustment in householders’ energy consumption behaviour and the technology used to generate energy could provide significant financial savings and contribute significantly to the reduction in carbon emission and energy consumption. This will allow significant benefit to the local economy and the energy sector in Libya but at the same time could provide sustainable energy resources for Europe on the long term. [ABSTRACT FROM AUTHOR]

This paper aims to assess the renewable energy capacity of Turkey in order to consider main priorities in the energy policy of Turkey. In this paper, renewable energy potential and regulatory conditions are discussed in Turkey in comparison with European Union. The results of the study implemented within the framework of EnviroGRIDS project indicated a promising yet very susceptible future for the implementation of renewable energy power plants in Turkey. The forecasts have shown that the solar power potential utilization is becoming more significant after 2020. The projections for 2050 indicate that electricity consumption from small and medium renewable energy sources including solar and wind will constitute 15% of the total, whereas the solar thermal will constitute around 16%. Geothermal and other renewables will remain around 3%. According to the high demand scenario, in 2050 the share of hydropower in overall electricity generation will be 12%, followed by solar power at 7% and wind power at 3%. Additionally, renewable energy policy and regulations in Turkey and in EU are overviewed in this study. On the contrary to EU, the constant feed-in tariff amount does not consider capital investments of specific energy sources in Turkey that brings disadvantage to the implementation. However, new regulations published and currently applied should be accepted as milestones in acquisition period of Turkey in EU. [ABSTRACT FROM AUTHOR]

In this paper, a different approach of standalone hybrid distributed generation has been shown. Due to the intermittent nature of the renewable energy resources, the reliability of the power system is decreased using single renewable energy source based electricity supply system. To overcome the problem the size of the storage system exceptionally large which increases the overall cost of the system and drastically reduces the flexibility. To resolve the problem a standalone hybrid power supply system is designed by integrating the solar and wind energy to generate electricity. The hybrid system increases the generation capacity without increasing the storage unit and maintains reliable electricity to the consumer. The proposed system has been modelled using Matlab/Simulink and verify under variable sources and load condition without compromising with the power quality issue. [ABSTRACT FROM AUTHOR]

Transnational power cooperation contributes to promoting the large-scale use of renewable energies in Asia, but how to develop the structure of power transmission network deserves careful investigation. This paper thoroughly investigates the structure of power investment and transmission network in China and neighbouring countries, aiming to promote the large-scale use of renewable energies around Asia. Various power-generation and power-transmission technologies are considered in detail, and transnational power interconnection risk cost and carbon emission cost are embedded into a bottom-up optimization model. The future power-generation structures and networks installed under various policy scenarios are analysed in detail, and the corresponding economic, carbon emission reduction and renewable energy consumption benefits are evaluated. The results show that power transmission between China's internal regions and neighbouring countries can save $56.7 billion for the entire power system through the large-scale grid integration of renewable energy. The installed capacities of wind power, solar power, and hydropower renewable energy power generation could be increased by 141 GW, 163 GW, and 58 GW, respectively. The construction of transnational transmission lines from Central Asia to Northwest China, Mongolia to North China, the Russian Far East to Northeast China, and Northeast China to South Korea could effectively promote the utilization of renewable energy in the Russian Far East, Mongolia and Central Asia and further reduce carbon emissions in China, Japan and South Korea. • It examines how to construct a power investment and transmission network in Asia. • Various technologies, risks and costs are considered based on bottom-up model. • Huge benefits exist for power transmission between China and neighbouring countries. • Various power-generation structures and networks installed are analysed in detail. • Suggestions about power investment and transmission are given for Asian countries. [ABSTRACT FROM AUTHOR]

Abstract: Solar is one of the many sources of renewable energy, and Concentrating Solar Tower (CST) is one of the most potential technologies in extracting solar energy. Thermal efficiency of CST is high and suitable to be implemented in a tropical climate country such as Malaysia which is located between at 10 to 70 North latitude and 1000 to 1200 east longitude. Further, Malaysia's direct normal irradiation (DNI) in tropical climate is almost constant throughout a year with the irradiation around 1500 to 2000 kWh/m2. Therefore the aim of this paper is to mathematically calculate the CST field layout in Malaysia in term of thermal efficiency based on cosine efficiency, atmosphere efficiency and mirror efficiency. The preliminary result from this paper shows Malaysia is a suitable location to develop CST with average of atmospheric transmittance efficiency and cosine efficiency of 94% and 63% respectively and the overall optical field efficiency is 52%. In addition, the atmospheric transmittance and cosine efficiency has high value but the efficiency gradually decreases whenever the distance increases. Nevertheless further investigation in term of solar irradiation and raining pattern in Malaysia is needed. [Copyright &y& Elsevier]

Abstract: The widespread use of the renewable energies requires compulsorily the development of new technological solutions for the efficient employment of these resources, such as small size, cogenerative power plants. A small volumetric steam engine may be considered an interesting device for an efficient and flexible use the heat generated by biomasses combustion or solar thermal collectors. In effects, this kind of engine may be operated with different kind of fluids, is quite insensitive to high degrees of humidity at the end of the expansion and is able to manage small volumetric flow rates with no losses in conversion efficiency. This paper shows the development of a rotary steam engine derived from a Wankel internal combustion engine. This engine was taken into account for this use due to its low bulk, vibration and noise running. Moreover, its use as an external combustion engine overrides its typical disadvantages that mainly belong to the combustion phase. The numerical modeling and the experimental tests using compressed air in a first prototype are shown in this paper. The results of the experiments allowed the validation of the model developed and this was employed to carry out a first optimization of the engine by means of the increase of the discharge coefficient of the exhaust valves. [Copyright &y& Elsevier]

Highlights • Capacity expansion planning model for the integration of CSP-TES. • Evaluation of the systemic economic and operational benefits provided by CSP-TES. • Analysis of multiple technology and policy scenarios for the Chilean power system. • Study of complementarities between CSP-TES and other technologies. • Investigation on the role of CSP-TES as a flexibility provider to the system. Abstract This paper presents a study about the impacts of the integration of concentrated solar power (CSP) with thermal energy storage (TES) in electric power systems. The main tool for this study is a comprehensive long-term power system capacity expansion planning model that integrates a specific module to represent the operation of CSP-TES power plants. The model determines the optimal investments on generation and transmission assets over a twenty-year planning horizon, ranging from 2018 until 2037, and employs projections for the various parameters involved (e.g. load growth, capital costs for the different generation technologies, fuels costs). One of the main features of the model is its ability to capture the hourly operational dynamics of the system through the consideration of multiple representative days for each of its investment periods. This feature allows a better understanding of the role of CSP-TES as a significant provider of flexibility to support a high penetration of variable renewable energy sources, as compared with traditional planning models based on load blocks. The model is applied to a case study for the Chilean electricity system. In order to study the impacts of CSP-TES, various scenarios of future capital costs and carbon tax levels are defined and analyzed for two market dominant CSP-TES technologies. The results show that for low CSP-TES capital costs, or high carbon taxes, the integration of CSP-TES in the system is significant towards year 2037, potentially reaching about one third of the total dispatched energy in the Chilean electric power system, yielding important operational, economic, and environmental benefits. [ABSTRACT FROM AUTHOR]

Abstract: Many of the solar panels throughout the world are positioned with the fixed angles. To maximize the use of the solar panel we use a solar tracker which orients itself along the direction of the sunlight. The solar tracker positions the panel in a hemispheroidal rotation to track the movement of the sun and thus increase the total electricity generation. This paper focuses on the development of new approach to control the movement of the solar panel. The purpose of this paper is to simulate and implement the most suitable and efficient control algorithm on the dual-axis solar tracker which can rotate in azimuth and elevation direction. The simulation gives the tracker angles that position the solar panel along the sun''s rays such that maximum solar irradiation is absorbed by the panel. [Copyright &y& Elsevier]

Abstract: An experimental system was developed and tested in order to investigate the exergetic performance of a solar photovoltaic system (PV) assisted earth-to-air heat exchanger (under ground air tunnel) that is used for greenhouse cooling at the Solar Energy Institute, Ege University, Izmir, Turkey. This system was under operational conditions successfully during the 2010 summer cooling season. This paper provides the experimental results obtained between 18th of August and 26th of August of in 2010. Exergy destruction in the system was calculated and presented in this paper using a reference temperature of 15°C. Results are discussed and interpreted in the paper for various performance metrics, such as the effect of climatic conditions and operating conditions on the system performance. Results show that the system may be satisfactorily used for greenhouse cooling in the Mediterranean and Aegean regions of Turkey. [Copyright &y& Elsevier]

Highlights • Operational frequency deduced both analytically and computationally. • Previously untested cooling configuration found to be the optimal. • Development of validated computer model of physical system. • Liquid piston instability linked to Rayleigh-Taylor phenomenon. • Liquid piston maximum acceleration limit identified. Abstract The objective of this research project is to develop a solar-powered refrigerator in the lower capacity range of up to 5 kW of cooling power. With the use of liquid pistons and one of the most efficient thermodynamic cycles known, the Stirling cycle, this product has the potential to outperform rival solar cooling technologies while providing inexpensive, reliable, quiet, environmentally-friendly, and efficient solar cooling for residential use, due to its straightforward manufacturing, simple design and inert working gas. Presented in this paper are the newest results of the theoretical and experimental investigation into deducing the key design parameters and system configuration of the so-called Liquid Piston Stirling Cooler (LPSC), which will help lead to optimal performance. Computer models of the complex unconstrained system have been constructed and validated using the modelling software Sage and shown to replicate system behavior with reasonable accuracy in experiments. The models have been used to predict system improvements and identify limitations imposed by the use of liquid pistons. The results to date provide a unique insight into a relatively little studied area in Stirling cycle research. [ABSTRACT FROM AUTHOR]

Energy crisis is one of the most crucial topics in today's world. Conventional energy resources are not only limited and costly, but also the prime cause for environmental pollution. The environmental pollution and rising cost of the fossil fuels have drawn considerable attention to renewable energy sources. Solar energy, being the cleanest and most reliable renewable energy source, is widely utilized in thermal systems to heat water and air. It offers a vast opportunity for public and private organizations to reduce carbon emissions and cut electricity costs. A viable approach to maximizing the solar panel efficiency is solar tracking. This paper, therefore, proposes an automatic microcontroller-based solar tracker with a hybrid algorithm for locating the sun's position. The proposed hybrid solar tracking algorithm combines both sensors and mathematical models to determine the precise sun's position, thereby harnessing optimal solar energy for all weather conditions. Experimental results consistently show that the hybrid solar tracking algorithm can yield higher solar power that the traditional active and chronological algorithms. A webpage was also developed to facilitate real-time monitoring of solar data. As such, the solar tracking process is fully automated, maximizing the collection and management of solar energy for solar thermal systems. [ABSTRACT FROM AUTHOR]

In this paper we present the results of monitoring a building integrated photovoltaic (BIPV) system, which was installed in Medio San Juan (Andagoya), Colombia. The system is operating in the Building of Renewable Energy of Chocó - CERCHOCO - and it is composed of a 20 kW photovoltaic generator connected to the electrical grid through a 20 kW three-phase inverter. We installed a monitoring system for measuring and analyzing the performance and power quality of the BIPV system. The meteorological and solar radiation data in the site of installation are also analyzed to correlate with system performance. On the basis of 2016 monitoring results, the performance of the BIPV system has been analyzed for component perspective (PV array and inverter) and global perspective (system efficiency, electrical energy and power quality etc.). Energy analysis and economic evaluation revealed that to get a trade off between energy and economic viability, the BIPVS installations must be heavily subsidized. [ABSTRACT FROM AUTHOR]

Photovoltaic systems have a reliable method to generate electrical power from direct solar irradiance. Their efficiency is only up to 20% in real operating circumstances and is affected adversely by the inevitable temperature rise in their surface. Passive, active or combined cooling methods are applied to reduce operating temperature to a suitable level, depending on specific application. A Great body of literature has been investigating different PV cooling methods and techniques to reach optimized system efficiency and cooling effect. It is critical for both researchers and practitioners to have a thorough understanding and awareness of the most recent advances and existing gaps. Although there are certain review papers in this field, it is necessary to have up-to-date reviews of the most recent progress and research since the previous ones. In the present work, the main focus was to provide a review of the most recent studies and to compare their outcomes to provide a reference for practitioners and researchers. The holistic classification and evaluation of all the possible cooling technologies were provided in order to draw a comparison between various cooling approaches. Based on the analysis obtained, cooling techniques can ensure improvement in electrical efficiency in a range from 1% to 53% with expected decrease in the photovoltaic panel's surface operating temperature from 1.8 °C to 46 °C. It was also found that spectrum filtering and jet impingement indicated highly remarkable enhancements. The other factors, such as the size of the examined photovoltaic panel, photovoltaic technology, as well as climate circumstances have a strong impact on the cooling performance besides the selection of the specific coolant. The necessity for integral evaluation (performance, economic and environmental) of cooling techniques was also identified as key issue. • Cooling technologies enhance the performance, durability, and lifetime of photovoltaic technologies. • Passive cooling techniques have less performance improvement when compared to active ones. • The size of the PV panel can strongly affect cooling performance. • The economic and environmental aspects were weakly investigated. [ABSTRACT FROM AUTHOR]

Researchers are continually striving to improve the efficiency of photovoltaic panels which contain solar cells that convert light energy to electrical energy. The objective is to improve photovoltaic (PV) efficiency by maintaining it below maximum allowable temperature. Accordingly, the excess in heat must be dissipated efficiently in order to avoid excessive high temperatures, which have an adverse effect on the electrical performance of the cell. Therefore, in this paper an experimental study is presented to enhance the performance of PV panels using Aluminum finned plate, and cooling under natural convection. The use of heat sinks has been conducted to address this problem by using an optimum design of Aluminum finned plate. The results show that the use of an Aluminum finned plate has increased the solar to electrical conversion efficiency by 1.75%, and the output power by 1.86 Watt. [ABSTRACT FROM AUTHOR]

Building integrated photovoltaics (BIPV) is one of the most promising solutions to generate renewable electricity in the built environment. BIPV applications can replace regular building components into prefab integrated components that at the same time generate electricity, contributing to the aesthetics in the built environment. In this paper we thoroughly review the existing BIPV stakeholders, the BIPV ecosystem and policy and legislation for BIPV in the Netherlands. The information that is provided throughout this research and the conclusions that were drawn should be taken into account by the government, academia and the BIPV industry when further designing the BIPV (export) strategy for the Netherlands. [ABSTRACT FROM AUTHOR]

• First reviews on coupling utilisation of thermal sources in vapour compression heat pumps. • The existing thermal source coupling attempts in applied energy fields are summarised and compared. • Design features and performance enhancement principles are analysed in detail. • Recommendations for research and marketisation of energy source coupling methods are made. Vapour compression heat pump provides efficient cooling and heating through the use of various renewable energy sources and plays a significant role in the energy conservation of modern buildings. Its performance enhancement gains increasing attention under the background of conventional energy and environmental crisis. Since the efficiency of a heat pump cycle is closely related to its thermal source condition, a stable high-temperature heat source or low-temperature cold source could benefit its heating or cooling efficiency a lot. Following this improvement strategy, significant progress has been made over the past years on the use of different renewable energy sources as coupled thermal sources of heat pumps. However, a specialised review that summarises relevant studies remains to be published. This paper aims at presenting operating mechanisms, characteristics, benefits, and limitations of different energy source coupling methods for heat pump performance enhancement towards its building application. The most concerning research on solar-assisted air source heat pumps, solar-assisted ground source heat pumps, and air-ground dual source heat pumps is emphasised. The existing thermal source coupling attempts under other renewable energy fields, such as waste heat, biomass, and water sources, are also summarised. Recommendations for further research and marketisation of such technologies are made based on detailed performance characterisation and comparison. The review is expected to benefit researchers in heat pumps and relevant applied energy fields to understand the challenges and opportunities in thermal source coupling technology and to promote its research and application development. [ABSTRACT FROM AUTHOR]

Denmark has a national political goal of a 100% renewable energy supply in 2050. This requires a comprehensive transition of the energy system. For some decades, district heating in Denmark has been contributing to high fuel efficiency as well as to the integration of the electricity and heating sectors. Large-scale compression heat pumps would improve the integration between the district heating and power sectors by utilising the fluctuations in the supply from wind power, solar photo voltaic and other sources. Previous studies indicate that the introduction of heat pumps in Denmark will have a positive impact on the total costs for energy supply in the transition towards 100% renewable energy. In this paper, this is further investigated to assess the feasibility of heat pumps in the Danish energy system. The assessment is made by applying two different energy system analysis tools, named EnergyPLAN and MODEST. The comparison and discussion of these tools is a secondary purpose of the study. In general, the results show a potential for introducing heat pumps in Denmark between 2 and 4 GW-thermal power and a total potential benefit around 100 M€/year in 2025. [ABSTRACT FROM AUTHOR]

Due to the increasing energy consumption of the world, new alternative energy sources are needed. The alternative energy resources can be classified into three categories such as fossil fuels energy resources, renewable energy resources, and nuclear energy resources. Solar energy is a very commonly used renewable energy resource for generating electricity and heating water. In this paper, establishing a solar energy system is handled as an investment analysis problem whose parameters are defined under uncertainty. Therefore, neutrosophic sets as a mean of dealing with uncertainty have been preferred to capture this vagueness and impreciseness. Neutrosophic sets are one of the extensions of intuitionistic fuzzy sets, which use an indeterminacy function unlike the other extensions of fuzzy sets. This paper proposes a new neutrosophic investment analysis method by using interval-valued parameters to evaluate solar energy systems. In the application section, three different types of solar energy systems are evaluated by the proposed method. It is observed that the proposed method presents big flexibility to experts and it gives effective and efficient results. [ABSTRACT FROM AUTHOR]

Innovations in Heating, Ventilation, and Air Conditioning (HVAC) systems are continuously required to provide a better, healthier and more productive and sustainable built environment for building occupants with minimized energy or cost consumption. This paper provides an overview of the HVAC technologies and systems used in 212 solar-powered houses developed through 13 U.S. Department of Energy Solar Decathlon (SD) competitions. Some comments and discussions on the HVAC technologies and systems used in the SD competitions were also provided. The review was carried out based on the information available from the organizer's project reports and equipment summary, team project manuals, and construction drawings available on the SD official websites as well as the published research papers and textbooks. It was found that 84.9% and 89.6% of the competition teams used heat pumps for space heating and space cooling, respectively, among which air-to-air heat pumps were used by approximately 50% of the competition teams. A wide range of energy technologies such as phase change materials, night-time radiative cooling, evaporative cooling, desiccant dehumidification, and energy/heat recovery ventilators have been used to reduce the electricity consumption of the HVAC systems. Energy/heat recovery ventilators were used by more than 55% of the teams in each competition held after 2005. Phase change materials were also frequently used in the competitions held in Europe. The SD competitions provided an excellent platform to showcase innovations of the HVAC technologies in residential buildings. [ABSTRACT FROM AUTHOR]

In this study, a solar based Rankine cycle and geothermal based system for multigeneration is designed and developed. It consists of a Rankine cycle with reheating for power generation, an absorption chiller cycle for cooling, a drying process to dry wet products, useful heat from the condenser of the Rankine cycle, and other useful heat out from heat exchangers. The overall energy and exergy efficiencies of the single generation and multigeneration systems are studied, and it is observed that the energy efficiency of the multigeneration system is higher than the single generation system. The energy efficiency of the single and multigeneration systems are 7% and 37%, respectively. Similarly, the overall exergy efficiencies for the single generation and multigeneration systems are also studied and presented in this paper. In addition to this, parametric studies are performed to observe the effects of different substantial parameters, namely inlet pressure and temperature of the turbine, and reference environment temperature in order to investigate the variations in the system performance in terms of the energy and exergy efficiencies. [ABSTRACT FROM AUTHOR]

• Deep attention ConvLSTM is first proposed for photovoltaic (PV) power forecast. • Attention mechanism is first introduced into PV power forecast. • Attention adaptatively fuses clear-sky prior knowledge and historical information. • Significantly improvement than conventional PV power forecast methods is achieved. Photovoltaic (PV) power is an important way to utilize solar energy. Accurate PV power forecast is crucial to the large-scale application of PV power and the stability of electricity grid. This paper proposes a novel method for short-term photovoltaic power forecast using deep attention convolutional long short-term memory (ConvLSTM) network and kernel density estimation (KDE). ConvLSTM has strong ability to automatically extract the information from multiple variables related to PV power and the temporal information from historical PV data. Considering that clear-sky solar radiation is an important physical prior knowledge in PV power generation, attention mechanism is innovatively introduced into ConvLSTM to dynamically and adaptively adjust the weights of the physical prior knowledge and the historical PV data in forecast. KDE is used for estimating the joint probabilistic density function and giving the probabilistic confidence interval. Experiments in the three-year actual photovoltaic power data of two provinces in Belgium verified the effectiveness of the proposed method. Comparison experiments were made with naive persistence and other eight conventional methods including autoregressive integrated moving average with exogenous variable (ARIMAX) model, convolutional neural network (CNN), long short-term memory (LSTM) network, multilayer perceptron (MLP), support vector regression (SVR), extreme learning machine (ELM), classification and regression tree (CART) and gradient boosting decision tree (GBDT). Experiments show that the proposed method can realize the optimal fusion of the historical data and clear-sky prior knowledge, and significantly improve the PV power forecast accuracy in all seasons of a year. [ABSTRACT FROM AUTHOR]

With around 40% of the population without access to electricity but also a high penetration of solar home systems in its off grid areas, the case of Bangladesh is a very strong reference for the applicability of the Sustainable Energy Access for All (SE4A) goals. Nonetheless, while the solar home system program with 3.6 million systems has gained worldwide recognition, there are considerable limitations in the usage of such systems, in particular in the ability to provide access to higher tier energy services for productive use. Minigrids, on the other hand, could provide this access but have yet to proof both scale and commercial viability. This paper provides critical insides into the case of Bangladesh for a cost-effective route to the SE4All goals by applying practical and resource-efficient minigrid design principles. Planning and operation techniques are elaborated on in detail and concluded with a financial analysis for a hybrid solar-PV-Diesel minigrid that provides enhanced energy access in particular for productive use. In addition, implications on the business model are highlighted for developing minigrids in off grid rural areas of Bangladesh for hybrid minigrids ranging from 100 to 250 kWp while exemplarily showing how the three goals of the United Nation Sustainable Energy for All Initiative can be pursued in a mutually beneficial way. [ABSTRACT FROM AUTHOR]

In this paper we address the integration of a polygeneration system based on biomass with a concentrated solar power facility for the constant production of electricity over a year long. The process is modelled as a superstructure embedding two different gasification technologies, direct and indirect, and two reforming modes, partial oxidation or steam reforming followed by gas cleaning and three alternatives for the syngas use, water gas shift reactor (WGSR) to produce hydrogen, a furnace for thermal energy production and an open Brayton cycle. We couple this system with a concentrated solar plant that uses tower technology, molten salts and a regenerative Rankine cycle. The problem is formulated as a multi-period mixed-integer non linear programming problem (MINLP). The optimal integration involves the use of indirect gasification, steam reforming and a Brayton cycle to produce 340 MW of electricity at 0.073 €/kWh and 97 kt/yr of hydrogen as a credit. [ABSTRACT FROM AUTHOR]

As an end user of energy products, carbon dioxide capture and storage (CCS) system commonly requires a significant amount of energy to sustain a steady operation. As a renewable energy source, solar energy can supply plenty of thermal energy in different grades through various types of solar collector. Between the demand and supply sides, several technologies of solar thermal engineering can be applied as a bridge for an energy efficient design. In this paper, a technological framework for the energy efficiency in post-combustion CO 2 capture is further discussed as a second section of the two-part study. Based on existing research, several possible options of alternative energy supply to CCS system are analyzed, particularly for solar thermal energy. Moreover, some key design issues for the solar-assisted CCS system, such as integrated solar reactor with the regeneration component, are discussed as well. [ABSTRACT FROM AUTHOR]

Renewable energy can play an important role in India's climate change mitigation, as India has great potential for renewables, especially solar and wind. This paper analyses the role of renewables to meet India's possible 2050 climate change mitigation targets using a multi-region global energy system model called TIAM-UCL, where India is explicitly represented as a separate region. TIAM-UCL is a cost optimisation model. The climate policy is applied to all regions in the model based on equal per capita emissions of 1.3 tCO 2 by 2050. Analysis shows that renewable energy can play an important role to decarbonise the economy, especially the power sector. Two low-carbon scenarios are explored, the first allowing for carbon capture and storage (CCS) technology deployment and the second excluding this technology. In the first low-carbon scenario (LC1), the most critical renewable energy technologies in the power sector are biomass with CCS, solar and wind. In the second low-carbon scenario (LC2), without CCS, there is an even greater role for solar and wind. Over the whole Indian economy, by 2050 renewables contribute 57% of the total CO 2 reductions in LC1 (relative to a reference scenario with no CO 2 target) and 63% of the CO 2 reductions in LC2. [ABSTRACT FROM AUTHOR]

Over 400 colleges and universities have signed carbon reduction pledges through Second Nature. Nonetheless, a review of their greenhouse gas inventories shows that many universities continue to show limited or no progress in terms of renewable energy deployment and generation. One study from 2019 shows that it is now cheaper to build new renewable energy projects than it is to continue operating existing coal-fired power plants (for 74% of existing fleet). Meanwhile, another study shows that universities rarely achieve a positive economic net benefit when deploying solar on their campuses, despite the cost declines in solar and rising utility prices. This same study finds that these same projects accrue a positive social and environmental net benefit for the surrounding community that outweighs current economic subsidies, implying that increased subsidies for college solar deployment would, more often than not, pass cost-benefit analysis. This present study builds on the previous two studies and explores the question of whether state-level financial incentives have a meaningful impact on the deployment of renewable energy on college campuses. The thesis guiding this research is that universities in states with certain state-level financial incentives will be more successful in deploying renewable energy and in meeting their clean energy goals. The financial incentives being studied are limited to grants, tariffs, net metering (at retail rates), and solar renewable energy credits. This research paper shows that the presence of these financial incentives is positively correlated with renewable energy deployment across colleges, providing a starting map for policy-makers interested in supporting universities' renewable energy deployment in their states. [ABSTRACT FROM AUTHOR]

• Heating and cooling tests on a fully monitored large-scale pavement solar collector. • Thermal performance investigation of a controllable and configurable prototype. • Sensitivity analysis of design and operational parameters on system performance. • A great potential in reducing asphalt surface temperature to mitigate UHI effects. Solar energy harvesting as a renewable and sustainable energy source has been widely investigated in recent years across engineering fields. The use of Pavement Solar Collectors (PSC) can lead to clean energy production, an increase in road safety, prolong the service life of asphalt pavement, and can mitigate the Urban Heat Island (UHI) effect. This study describes a controllable large-scale research PSC prototype with high configuration flexibility, and full monitoring capability at the University of Antwerp, Belgium. Since small- or laboratory-scale setups do not reflect the behavior of actual projects, the present paper investigates the thermal response of a large-scale PSC in the Western European climate, including heating load, heat extraction capacity, and asphalt surface and profile temperature changes during heating and cooling experiments. The study shows that a low supply temperature compared to high (14 °C vs. 28 °C) can reduce the depletion rate of the stored thermal energy in borehole thermal energy storage up to 7 times. The sensitivity analysis indicates that an increase in flow rate from laminar to transient regime requires twice as much thermal power compared to the same flow rate changes within transient and turbulent regimes. The maximum average daily efficiency of the PSC could reach 34% with a flow rate of 4 l/min. The experimental results showed that increasing the pipe length from 50 m to 200 m reduces the cumulative power extraction capacity by up to 48%. Furthermore, the PSC system shows great potential in reducing the asphalt surface temperature (up to 12 °C) to mitigate the UHI effects. Finally, the PSC system effectively controls the temperatures of the interface zones to reduce the rutting distress in the summertime and lower the potential of cold thermal crack developments and brittle shear failure behavior in wintertime. [ABSTRACT FROM AUTHOR]

Abstract: Successful development of renewable energy technologies like solar photovoltaic energy (SPV) critically relies on its understanding and acceptance by consumers and institutional customers. Even in contexts of favorable support at the general level like in Brazil, their implementation faces multiple challenges, including low awareness, misperceptions, insufficient communication, and eco-labels' mixed record as information enhancing tools. This paper discusses how market research has been instrumental in developing the first SPV venture in Brazil, by identifying public's beliefs and level of support for alternative energies, and by testing reactions to a solar energy eco-label scheme proposed as key communication tool. The study indicates that expectations for return on investment are affected by a sustainability penalty, as well as by price and adaptation barriers. It also reveals an assessment gap between the concept and design of eco-label, which led to a new eco-label design capable of better addressing unfavorable beliefs, integrating expectations, and improving overall acceptance. [Copyright &y& Elsevier]

Abstract: With the construction industry moving rapidly towards Building Information Modelling (BIM), it is essential that various analysis tools used in the Architecture, Engineering and Construction (AEC) domain are interoperable with a non-proprietary open BIM schema such as the Industry Foundation Classes (IFC). The UK government will be requiring fully-collaborative BIM in all public sector projects by 2016 and is also chasing the target of achieving zero-carbon buildings by 2019. This dual target will require the use of renewable energy analysis tools in the early stages of the building design process and establish the need for these tools to be IFC-compliant. This paper presents a conceptual framework for developing IFC-compliant renewable energy simulation tools using a multi-model concept in which the IFC data model provides partial input data required to run simulation models. A prototype has been developed as a ‘proof-of-concept’ for an IFC-compliant solar PV simulation tool. The prototype has been validated against other solar PV simulation tools such as PV*Sol, RETScreen® and HOMER to provide credibility to the simulation model. The developed conceptual framework is applicable not only to solar PV simulation but other renewable energy simulation models as well, thereby making an IFC-compliant renewable energy modelling tool capable of conducting, energy, carbon emissions and financial analysis. [Copyright &y& Elsevier]

Abstract: Renewable energy sources represent an alternative to fossil fuels like coal, oil and gases. The pollution generated burning fossil fuels for industrial development and the limited character of energetic fossil resources imposes the necessity to replace them with other sources of energy. The renewable energy sources have some specific characteristics that involve a process of implementation adapted to the region particularities. The paper present a scenario for implementing the renewable energy sources into the Romanian economy, taking account to the specific socio-economic aspects of Romanian society. The target of this scenario is 2020 when Romania needs to ensure 24% of gross energy consumption from renewable sources. [Copyright &y& Elsevier]

Rather than using individually distributed energy storage frameworks, shared energy storage is being exploited because of its low cost and high efficiency. However, proper sizing and operations approaches are still required to take advantage of shared energy storage in distribution networks. This paper proposes a bi-level model to optimize the size and operations of shared energy storage in hybrid renewable-resource power generation systems. The upper-level model maximizes the benefits of sharing energy storage for the involved stakeholders (transmission and distribution system operators, shared energy storage operators and the various power plant owners) and the lower-level model minimizes the hybrid system operating costs. The benefits of this system were found to be: (1) reductions in wind and solar power curtailment and coal-fired generation costs; (2) peak shaving; (3) frequency regulation; and (4) a deferral of upgrades to power transmission and distribution facilities. To fully realize the long-term planning and short-term operational interactions of shared energy storage, a bi-level nested genetic algorithm was designed to solve the proposed model. By continuously updating the solutions, a set of optimal solutions were generated. To validate the approach, numerical tests were conducted, with the results showing that by properly sizing and operating the shared energy storage in distribution networks, the wind curtailment rate was reduced by about 10.2%, the solar curtailment rate was reduced by 14.2%, and the stakeholder benefits were around 154 million dollars. Further discussion is given on the benefits of shared energy storage investments. • Shared energy storage is planned and modelled in distribution networks. • A bi-level model is established for shared energy storage sizing and operation. • An interactive bi-level nested genetic algorithm is designed. • A comparative analysis is conducted to validate the shared energy storage feasibility. [Display omitted] [ABSTRACT FROM AUTHOR]

The classical optimal power flow problem is usually formulated with only thermal generators, in which the fuel used to generate power is limited and emissions from the network system are often ignored. Due to several promising features like renewability, richness, and cleanness, renewable energy sources have been drew growing attention. As a result, more and more renewable energy sources are penetrated into the electrical grid. In this paper, the standard IEEE-30 bus system is modified by integrating renewable energy sources as the case study, where the traditional thermal generators on buses 5 and 11 are replaced by wind generators, and bus 13 is replaced by solar generators. In addition, to address the intermittence and uncertainty of renewable sources, the Weibull probability density function is used to calculate the available wind power. Meanwhile, the lognormal probability density function is employed to calculate the available solar power. The optimal power flow with stochastic wind and solar energy is formulated as a multi-objective optimization problem. A multi-objective evolutionary algorithm based on non-dominated sorting with constraint handling technique are presented to solve it. In addition, another larger test system i.e., IEEE-57 bus system is selected to further verify the performance of the proposed approach in handling large dimensional problem. Simulation results indicate that proposed approach can obtain competitive compromise solution on different optimization objectives. • OPF incorporating renewable energy sources such as wind and solar is formulated. • The intermittent and uncertain of wind and solar power is matched by different density function. • The superiority of feasible solutions (SF) is used to effectively handle constraints in OPF. • Two effective constraint multi-objective methods are proposed. [ABSTRACT FROM AUTHOR]

Abstract: There are many immediate adverse effects on the environment such as large amount of greenhouse gases and pollutants emissions from the burning of fossil fuels for electricity generation. Photovoltaic (PV) systems are promising solar energy applications to generate electricity without emitting pollutants and requiring no fuel. In modern urban cities, most buildings are high-rise with limited spaces for PV system installation, the concept of building integrated photovoltaic (BIPV) would be an appropriate alternative form of the application. This paper studies a medium size grid-connected BIPV system mounted in an institutional building. Technical data including solar radiation and energy output were analyzed. The operational performance and electricity benefits of the BIPV system were examined in terms of cost, energy and environmental aspects. The monetary, embodied energy and greenhouse gas payback periods were estimated and reported. To shorten the payback periods, the BIPV system should incorporate with more passive energy-efficient architecture designs. This on-site measurement contributes the most accurate method of obtaining reliable data for determining the performance of various designs under the actual operating environments for evaluation. [Copyright &y& Elsevier]

Abstract: A triple-state LiCl–H2O absorption system with a power of 10kW that is fully driven by solar thermal energy has been designed and installed in a detached house in Spain. The system dissipates heat through a swimming pool, avoiding the need for a cooling tower. The system is fed using a solar thermal system with an area of 35.54m2. The behavior of the system was monitored for a full year. The design and the calculations for the thermal requirements are presented, and the values of the coefficient of performance (COP) and the expected temperatures are compared with those obtained experimentally. This paper demonstrates that the actual values are slightly lower than the simulated values. The experiment has validated the possibility of using a swimming pool as a sink for heat dissipation. The economic analysis shows that the internal rate of return (IRR) reaches 12.45% while achieving a 68% reduction in greenhouse gasses GHG emissions. The results show that this approach can add great value to solar thermal energy systems while avoiding problems due to high temperatures during the summer months. [Copyright &y& Elsevier]

Abstract: With increased penetration of solar as a variable energy resource (VER), solar photovoltaic (PV) power production is rapidly increasing into large-scale power industries. Since power output of PV systems depends critically on the weather, unexpected variations of their power output may increase the operating costs of the power system. Moreover, a major barrier in integrating this VER into the grid is its unpredictability, since steady output cannot be guaranteed at any particular time. This biases power utilities against using PV power since the planning and overall balancing of the grid becomes very challenging. Developing a reliable algorithm that can minimize the errors associated with forecasting the near future PV power generation is extremely beneficial for efficiently integrating VER into the grid. PV power forecasting can play a key role in tackling these challenges. This paper presents one-hour-ahead power output forecasting of a PV system using a combination of wavelet transform (WT) and artificial intelligence (AI) techniques by incorporating the interactions of PV system with solar radiation and temperature data. In the proposed method, the WT is applied to have a significant impact on ill-behaved PV power time-series data, and AI techniques capture the nonlinear PV fluctuation in a better way. [Copyright &y& Elsevier]

Abstract: This paper aims to develop a novel hybrid system for wind and solar energy forecasting. The uniqueness or novelty of the proposed system is obvious because there are no available research works related to the hybrid forecasting system of renewable energy. The proposed ‘Hybrid (wind-solar) Energy Forecasting Model’ is dedicated to short-term forecasting (three-hour ahead) based on artificial neural network (ANN) learning algorithm. The network learning or training algorithm will be implemented using ANN Toolbox which is widely used simulation software incorporated in MATLAB. Eleven different climatological parameters of the last six years of a typical subtropical climate based area Rockhampton in Central Queensland; Australia has been taken for analysis investigation purpose and will be considered as the inputs of ANN model for hybrid (wind-solar) energy forecasting. The ANN will be trained in such a way that with minor modifications in the programming codes, it can perform the hybrid forecasting within the range from hourly (short term forecasting) to daily (medium term forecasting). This feature is one of the major innovations and indicating the great robustness of the proposed hybrid renewable energy forecasting system. As the hybrid forecasting system is quite a novel approach, the accuracy of the system will be revealed by comparing the results with the corresponding values of stand-alone forecasting model referred to as the persistent model. Finally, the fully developed system package may be commercialized and/or utilized in further research projects for researchers to analyze, validate and visualize their models on related domains. [Copyright &y& Elsevier]