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Residential consumers in the U.S. have demonstrated a growing interest in rooftop photovoltaic (PV) systems, resulting in increased adoption over the last decade. However, this has diminished utility revenues, and policymakers have expressed concerns about inequitable consumer access to publicly-funded rooftop PV adoption incentives. In response to these concerns, policymakers and utility companies are changing their policies to discourage rooftop PV adoption. Alternative renewable energy models, such as utility-provided community solar programs, offer a potential solution. However, when designing such programs, it is important to consider the potential impacts on different system stakeholders, including utilities, policymakers, and solar installers. This paper describes an agent-based model that predicts the performance of different residential distributed solar models with respect to these stakeholders' objectives. In this model, consumer agents residing in an urban utility territory decide in each time-step whether they will adopt a particular renewable energy model, and the impacts of their adoption decisions on stakeholder performance metrics are captured over time. Simulation results suggest that if community solar program premium prices are set appropriately, all stakeholders can benefit: the utility can recover part of its revenue losses even as rooftop PV adoption increases, solar installers’ businesses can thrive, and increased renewable energy adoption can be achieved equitably. The proposed modeling methodology can help to inform design decisions of distributed solar energy models that avoid benefiting some stakeholders at the unnecessary expense of others.

This study was conducted to ascertain how the use of recycled materials instead of virgin materials affect the installation of renewable energy systems for the energy transition of buildings. LCA was used to estimate the life cycle energy use and GHG emissions of building and renewable energy systems with and without using recycled materials. For the case study, a public building and four representative photovoltaic (PV) systems were selected. National recycling standards and processes were considered for suggested recycled materials. In general, replacing virgin material with recycled counterpart reduced embodied GHG emissions more than embodied energy. However, due to high carbon intensity of operation energy and building materials without available counterparts, using recycled materials reduced the life cycle energy use and GHG emissions of the case building by 4.9% and 3.3%. Among four PV systems, using recycled materials was most significant in the single crystalline-silicon (sC-Si) PV system, 44.5% reduction of energy use and 41.3% reduction of GHG emissions. Therefore, when recycled materials are used for achieving the energy transition of the case building with the sC-Si PV system, the PV system requirements could be reduced by a maximum of 9.6% for energy payback and 4.9% for GHG payback. This study demonstrated that the use of recycled materials is effective at reducing the embodied energy and GHG emissions of PV systems as well as buildings. To achieve carbon-neutral buildings, particularly, the use of recycled materials based on a thorough LCA should be considered in addition to renewable energy system.

Renewable Energy and Sustainable Supply Chain Management have been extensively studied over the last decade. However, techniques based on the modelling and simulations have not been applied extensively in the supply chain of renewable energy. The main purpose of this study is to identify the latest System Dynamics contributions and trends related to the supply chain of renewable energy. An overview of works published in several journals and related to the application of the System Dynamics approach in Renewable Energy Supply Chain (RESC) is provided. Only 10 papers focusing on the application of system dynamics in RESC were found and these were classified into three groups of analysis. Although the literature is scarce, this work shows the importance of system modelling considering: (i) improving the understanding of supply chain in renewable energy and (ii) developing modelling and simulation approaches in renewable energy systems. This paper represents a source for elaborating a System Dynamics framework applied on RESC and provides a comprehensive bibliography of papers published in the last decade.

Hydropower plays an important role in the safe, stable and efficient operation of power systems, especially with current trends toward renewable energy systems. The total global potential of gross, technical, economic, and exploitable hydropower are still enormous in the future, and the developments of new hydropower stations (HPSs) are of great importance. For constructions of new HPSs, the condition of setting surge tanks (CSST) is crucial for various perspectives, e.g. safety, stability and economy of HPSs. In this review, the CSST are summarized and analyzed from the three aspects: regulation assurance, operation stability, and the regulation quality, with an aim of providing a reference and guidance for research and engineering applications regarding surge tanks. Upstream and downstream surge tanks in conventional HPSs and pumped storage power stations are all included. Moreover, a comprehensive comparison of CSST under different conditions is conducted. One of the main focuses of this review is on Chinese studies, for introducing many meaningful results written in Chinese to more readers all over the world.

Supercapacitors (SCs) have high power density and exceptional durability. Progress has been made in their materials and chemistries, while extensive research has been carried out to address challenges of SC management. The potential engineering applications of SCs are being continually explored. This paper presents a review of SC modeling, state estimation, and industrial applications reported in the literature, with the overarching goal to summarize recent research progress and stimulate innovative thoughts for SC control/management. For SC modeling, the state-of-the-art models for electrical, self-discharge, and thermal behaviors are systematically reviewed, where electrochemical, equivalent circuit, intelligent, and fractional-order models for electrical behavior simulation are highlighted. For SC state estimation, methods for State-of-Charge (SOC) estimation and State-of-Health (SOH) monitoring are covered, together with an underlying analysis of aging mechanism and its influencing factors. Finally, a wide range of potential SC applications is summarized. Particularly, co-working with high energy-density devices constitutes hybrid energy storage for renewable energy systems and electric vehicles (EVs), sufficiently reaping synergistic benefits of multiple energy-storage units.

Hydrogen storage systems (HSSs), are the backbone of feasible hydrogen economy. To provide a reliable renewable energy system, safe, cost effective and compact HSS is due. Physical storage systems involve the compressed gas, liquid and cryo-compressed techniques while material based one involves adsorptive materials, metal hydrides and chemical storage materials. In this paper, the features of a variety of HSSs are impartially discussed. The technical comparative analysis of the different physical and material based types of HSSs illustrates the paradoxical inherent features, including gravimetric and volumetric storage densities and parameters associated with storage and release processes, among these systems. Accordingly, no ideal hydrogen storage technique can be considered the best-fit for all stationary and automotive applications. Therefore, not only a unique HSS solution can properly provide the needs, but a set of complementary HSS solutions which may offer the system designer several options. This set of options can be hardly interpretable in case of the unclear definition of the application needs which may be time variant. Inside this review, the critical insights and recommendations about suitable applications for storage systems are provided. Different standards and codes alongside the corresponding tests are demonstrated for the different storage technologies. Moreover, storage vessels research work is overviewed for the different hydrogen storage technologies. In addition, the failure behaviour, criteria and prediction models are investigated for composite vessels subjected to high pressures and extreme temperatures degrading their mechanical behaviour and failure resistance.

Over the last few decades, multilevel inverters (MLIs) are being extensively utilized in many industrial and grid connected applications due to their numerous merits. With the recent development of renewable energy systems (RES), applications of classical MLI topologies are hindered due to their performance issues such as poor power quality, uneconomical structure and low efficiency. These performance issues and limitations in classical MLI topologies have attracted the researchers toward evolving new hybrid MLI topologies. In this article, a comprehensive analysis of these recent hybrid MLI topologies is done on the basis of some qualitative and quantitative performance indices. Special focus has been given to extensively review the influence of MLIs in grid connected renewable energy applications such as photovoltaic (PV) systems, wind energy conversion systems (WECS) and micro-grid. In order to provide the better insight about the working and performance of these MLI topologies, simulation results performed in MATLAB/Simulink environment are also presented.

This paper presents a technique for the optimal planning and design of hybrid renewable energy systems for microgrid applications. The Distributed Energy Resources Customer Adoption Model (DER-CAM) is used to determine the optimal size and type of distributed energy resources (DERs) and their operating schedules for a sample utility distribution system. Using the DER-CAM results, an evaluation is performed to evaluate the electrical performance of the distribution circuit if the DERs selected by the DER-CAM optimization analyses are incorporated. Results of analyses regarding the economic benefits of utilizing the optimal locations for the selected DER within the system are also presented. The electrical network of the Brookhaven National Laboratory (BNL) campus is used to demonstrate the effectiveness of this approach. The results show that these technical and economic analyses of hybrid renewable energy systems are essential for the efficient utilization of renewable energy resources for microgrid applications.

Solar energy is a clean source of energy and has been used widely for various applications. Exergy analysis, which discussed the grey areas of improvement in various application considers the entropy generations within the systems. Exergetic analysis has been widely used in the performance analysis and exergoeconomic analysis of renewable energy systems. The present study discusses the comprehensive review on exergetic analysis of solar assisted distillation systems with main focus on concentrated solar energy. For the same, general relations used for first law analysis, second law analysis, entropy generation and irreversibilities for each subcomponent is presented. Following this, the exergetic analysis work on Parabolic trough collectors (PTC), heat exchanger and distillation systems are reviewed comprehensively. The future direction for research work in the area of exergy analysis are identified and suitable conclusions are presented. It is expected that this comprehensive study will be beneficial to researchers involved in the second law analysis of solar based distillation systems.

In this paper, the contemporary development in multiple input dc-dc converters are identified and examined. The quest to mitigate the difficulties associated with employing renewables in distribution systems and electric vehicles (EVs) has yielded many new converter topologies. These new topologies have easier control, lower parts count, are cheaper and are worthy alternatives to the typical series or parallel connection of converters. The converters are identified by three divisions that bother on the isolation between the respective ports. The electrically connected converters do not have isolation between the ports, and thus, a dc link connects the ports. Electromagnetically connected converters use a dc-link to connect input ports, but the input ports and output port are isolated. In magnetically connected converters, input ports are separated by multiple winding transformer, just as the output port is isolated from the input ports by the winding. The formation, structure, characteristics, operation, merits and demerits of the converters will be presented. Thereafter, comparisons will be done based on the distinct features of the converters. This review identifies that converter properties depend on the specific application requirement and thus, no converter fulfills all demands in the industry. Prospective future research trends are suggested. This work aims to update on research done during the time gap since the last comprehensive reviews.

One of the great technological challenges in 21st century is the development of renewable energy technologies due to serious problems related with the production and use of energy. A new promising area of research grows rapidly which is called Nanotechnologies are considered nowadays one of the most recommended choices to solve this problem. This review aims to introduce several significant applications of nanotechnology in renewable energy systems. Papers reviewed including theoretical and experimental works related with nanotechnology applications in solar, hydrogen, wind, biomass, geothermal and tidal energies. A lot of literature are reviewed and summarized carefully in a useful tables to give a panoramic overview about the role of nanotechnology in improving the various sources of renewable energies. We think that this paper can be considered as an important bridge between nanotechnology and all available kinds of renewable energies. From the other side, further researches are required to study the effect of nanotechnology to enhance the renewable energy industry especially in geothermal, wind and tidal energies, since the available papers in these fields are limited.

This paper presents a review of a standalone and grid-connected hybrid renewable energy system (HRES) to supply AC loads. The configuration of the HRESs and interfacing power converters for connecting the energy sources to the AC bus is extensively discussed. An overview of the control concepts in an HRES and the application of the appropriate control schemes for system stabilization, effective injection of high quality power and proper load sharing are discussed. The different approaches for HRES design and control strategies for power converters in the recently published literature are also briefly addressed. Finally, this paper highlights the future developments in HRESs to increase the utilization of power generated from renewable energy sources (RESs).

Renewable energy is considered as a solution for mitigating climate change and environmental pollution; however, an important problem of the application of renewable energy systems (RESs) is that the evaluation of the sustainability of these systems is extremely complex. In order to assess the sustainability of renewable energy systems comprehensively, the use of sustainability indicators (SIs) is often necessary. Since sustainability indicators are necessary to reflect various aspects of sustainability, the development of a general sustainability indicator (GSI) including many basic sustainability indicators (BSIs) becomes critical. In this paper, the methods of selection, quantification, evaluation and weighting of the basic indicators as well as the methods of GSI aggregation are reviewed. The advantages and disadvantages of each method are discussed. Based on these discussion and the analysis of the uncertainties of sustainability assessment, an effective framework and its procedures of the development of GSI for renewable energy systems is presented. This GSI is not only able to evaluate all the sustainability criteria of RESs, but also can provide numerical results of sustainability assessment for different objective systems. The proposed framework in this study can be used as a guidance of the development of sustainability indicator for various renewable energy systems.

Hybrid renewable energy systems (RESs) are being widely utilized as an alternate source of energy for mitigating the rapidly increasing energy demand. Explicit representation of the results obtained from the impact analysis made on a newly proposed or an existing hybrid RES is complex, and it requires powerful visualization tools. Over the years, various visualization techniques were developed towards addressing this problem. Therefore, the use of visualization techniques are continuously growing and have been the focus of many researchers across the world. This review article presents a comprehensive analysis of the advancements in the use of different immersive visualization (IV) tools in state-of-the-art RES development. A total of 41 software packages and a collection of recently published research articles in the field of RES development incorporated with advanced IV tools was identified and critically reviewed based on its use-case, accessibility, complexity, robustness, immersivity, and adaptability. Finally, a list of fit-for-purpose software packages that could be used at different stages of the RES development is recommended. A summary of the current advancements in the use of the IV tools in RES development is presented to highlight the broader potential of multidisciplinary applications of the advanced IV tools in RES development.

An overview is provided of commercially-available biolubricants, along with the manufacturing technologies used to make them, and emerging production technologies that show promise. Ester-based biolubricants enjoy the most widespread commercial use, even though complex chemical modifications are required to improve their physicochemical properties. Renewable-hydrocarbon biolubricants can be more attractive because they possess desirable qualities such as superior cold-flow properties and oxidative and hydrolytic stability. In addition, hydrocarbon-based biolubricants are more similar to conventional lubricants and can be easily substituted using existing infrastructure and lubricant formulations. Current research on renewable hydrocarbons is heavily focused on hydrodeoxygenation of vegetable oils involving operating conditions in excess of 50 bar and 450 °C. Alternative routes such as those involving electrochemical decarboxylation through Kolbe electrolysis benefit from milder conditions and consume less hydrogen overall. A further benefit of Kolbe electrolysis is the potential for integration into renewable energy systems. Further research into this technology could open the doors to low-cost, high-quality renewable hydrocarbons for use as biolubricants.

Renewable energy systems (RESs) have been promoted for rural electrification as an answer to the growing energy needs of communities while simultaneously satisfying environmental and resource scarcity problems. These off-grid systems however have several challenges in the perspective of sustainability due to the technically and financially weak recipients and users of the projects. There is still, however, less detailed understanding how the technical and economic aspects of the projects can properly match the social aspects to promote sustainability. This paper aimed to further understand the challenges and social impacts of rural electrification projects using RES through a case study of a centralized off-grid solar plant in the Philippines. The study used multiple correspondence analysis (MCA) to identify essential user attributes which explain the users’ electricity consumption behaviors. The community cooperative had difficulties maintaining the facility in the long term due to financial and capacity related challenges. A holistic approach dealing with the technical, economic and social aspects in developing RES projects promote sustainability.

Renewable energy systems (RES) can impact landscape aesthetics and influence the public's perception of the landscape and their acceptance of large infrastructure projects. Perceptual processes have consequences for both physiological and behavioral reactions to visual landscape changes and have not been systematically assessed in the context of RES. In this paper, we measured participants' physiological (electrodermal activity) and behavioral (i.e., landscape preferences) responses to landscapes with different amounts of RES. The visual stimuli were composed of either a low or high amount of wind turbines and photovoltaic systems in seven different landscape types. Participants were asked to choose their preferred landscape image from pairs of sequentially presented images while we recorded their electrodermal activity. The results revealed that participants were significantly more physiologically aroused while viewing landscapes with high RES compared to landscapes with low RES. We also found that the participants significantly preferred landscapes with low RES to landscapes with high RES and that this effect was larger for some landscapes than others. The results also revealed significant differences in preferences among landscape types. Specifically, participants tended to prefer the more natural landscapes to the more urban landscapes. A systematic analysis of the visual features of these stimuli revealed a positive correlation between physiological arousal and the visual impact of photovoltaic systems. Overall, we conclude that both physiology and behavior can be relevant for studies of landscape perception and that these insights may inform planners and policy makers in the implementation of landscape changes related to RES.