Renewable Energy Focus最新文献

This study proposes a novel framework for smart homes to optimize energy consumption and production, leading to reduced costs and a more reliable grid. The framework schedules the use of controllable appliances and renewable energy sources while considering uncertainties in production, real-time market prices, and uncontrollable household loads. By incorporating both incremental and real-time pricing models, the system discourages excessive consumption during peak hours. The core innovation lies in a two-stage scheduling approach implemented using GAMS software. This method minimizes the expected total cost while accounting for limitations on controllable loads, power supply, production resources, battery performance, and overall home energy balance. Additionally, the framework leverages the previous day’s bilateral contract and allows residents to adjust desired lighting levels based on current market fluctuations. Simulations demonstrate the program’s effectiveness in reducing both net energy costs and peak load on the electricity grid.

Archimedean turbines have recently been installed in watercourses to convert the hydraulic power of water to electricity. As a new technology, they are under development now. Its geometric parameters’ optimization with heuristic optimizers hasn’t been considered so far. These parameters include the ratio of the inner to the outer diameter (diameter ratio), the pitch to the outer diameter ratio (pitch ratio), the tilt angle, and the fill factor which is the ratio of water depth in the screw’s bucket to the outer diameter. In this research, the efficiency prediction model of the Archimedean turbine was coded in MATLAB and validated with laboratory and field Archimedean turbine data. Then, particle swarm optimizer (PSO) and grey wolves optimizer (GWO) were developed and linked with the validated prediction model. The optimizers’ convergence was investigated; then, the turbine parameters were optimized to obtain the maximum efficiency. The best value of the tilt angle was found in the range 20–22.5°, and the best value of the fill factor was 1. The maximum mechanical efficiency of about 90% was found in this research. The overall results of PSO were better than GWO.

The manure biogas plant is a promising technology for the future. It represents a closed-loop system that reinforces the circular economy. However, effective and viable implementation requires optimization of the entire supply chain. In this paper, a cost optimization model for manure to electricity supply chain has been developed. The model aims to determine the best configuration for the biogas plant network (Decentralized/Centralized Biogas plant), identify the optimal locations and capacities, and give a distribution plan of materials flow within the supply chain while minimizing the overall costs. The novelty of this work consists in adopting a holistic approach that addresses a multi-region, multi-period and multi-product problem which considers seasonal variation in manure availability, different manure mixtures, the physico-chemical properties of manure and the technical aspects related to the biogas plant by adapting the open source tool OSEMOSYS. The model is applied to the Tunisian case study to provide the optimal pathway to achieve the Tunisian solar plan’s target of 100MW from biogas by 2030. As a result of the optimization, the optimal network of biogas plants across 6 regions in Tunisia is identified. Our results have shown that the LCOE of generating electricity across all regions ranges between 14.2 US$ cent/kWh and 19 US$ cent/kWh. Additionally, a sensitivity analysis on two key parameters distance and capital cost is performed.

A sizeable portion of the overall energy used by various industrial processes is thermal energy. This could be largely supplied by technologies of solar energy in countries with abundant solar energy, like Jordan. Many processes in dairy factories require heat at different temperatures. Hot steam is even necessary for some of these processes. Such high temperatures can be produced by concentrated solar power plants using a number of technologies, like linear Fresnel reflectors. This paper presents the optimization of the operating parameters leading to the best techno-economic performance of a linear Fresnel reflector that provides heat for a pasteurization process in a dairy factory. A processing rate was assumed to be of 100,000 liters/day of milk. After fixing all parameters involved in the design process, then the research work proceeds to optimize five operational parameters. These were fed to RESSSPI software; a solar energy simulator for industrial processes, resulting in 30 different simulations. The optimal operational parameters obtained were used for a techno-economic performance simulation of the plant. Results showed that the system turned out to be very feasible, both technically and economically. The heat produced by the solar system was 1362828.4 kWh, while the heat consumption by the process was 1480277.6 kWh representing 92.1 % of the heat energy required for the designated process. The solar energy utilization factor was 83.3 % resulting because of energy lost due to defocusing of the Fresnel reflectors. The payback period of the project was 3 years and the LCOE was 0.02970 €/kWh.

Electric Vehicles are emerging as preferred means of transport due to rising concerns regarding the increased harmful emission with fossil fuels. The integration of the EV in the distribution network has severe effects which create unbalance in the network and will lead to a reduction in the reliability of the network. This work deals with the impact analysis of the electric vehicle charging stations on the distribution system and assesses the hosting capability of the distribution system by formulating several scenarios. In this paper, the IEEE-33 & IEEE-69 bus systems have been modified to mimic the practical distribution network. The proposed formulation is done on MATLAB, and results show that up-to 40% EV penetration is tolerable by the existing distribution networks. and as the penetration increases, the permissible limit gets violated. This research work provides a comprehensive analysis of the impact caused due to residential and public based charging of electric vehicles and can be applied to different networks to assess the hosting capacity of the distribution network.

India’s power sector has undergone significant changes in recent years, driven by various policy initiatives aimed at promoting competition, improving efficiency, and increasing the share of renewable energy sources in the country’s energy mix. This manuscript provides an overview of the current state of the Indian power sector and their recent developments. The manuscript discusses the structure of India’s power sector, including the role of various players such as generation companies, transmission companies, and distribution companies. The manuscript then analyzes policy initiatives aimed at reforming the sector, these include the Electricity Act of 2003, which introduced competition in the generation and retail segments, the Ujwal DISCOM Assurance Yojana program, which aimed at improving the financial health of distribution companies, and, the Revamped Distribution Sector Scheme which has been approved by the Government of India to assist DISCOMs in improving their operational efficiencies and financial sustainability. The manuscript also discusses recent developments in the renewable energy sector in India, including the growth of solar and wind power, the implementation of renewable purchase obligations, and the introduction of competitive bidding for renewable energy projects. Finally, the manuscript examines the impact of recent developments on the performance of India’s power sector and the power exchange. It finds that while significant progress has been made in promoting competition and increasing the share of renewable energy, challenges such as the high cost of electricity and the financial health of distribution companies persist. The paper concludes by discussing potential areas for further reform and improvement in the sector.

Agrophotovoltaic (APV) or agrivoltaic systems are sustainable energy systems that can produce electricity and food from the same land area and conserve water. This study evaluates the performance, reliability, and economic viability of three solar photovoltaic (PV) systems: a monofacial and bifacial rooftop system and a monofacial agrivoltaic system in Chennai (12.8259° N, 80.0395° E). The agrivoltaic system integrating crops beneath outperformed the bifacial and monofacial systems, with a normalized daily average power output of 59.88 W and an efficiency of 16.89%, surpassing the bifacial (56.35 W, 14.45%) and monofacial (47.18 W, 12.49%) counterparts. The results show that the land equivalent ratio (LER) of 1.85 for an agrivoltaic system emphasizes efficient land use by combining crop cultivation with electricity generation. Furthermore, economic analysis shows that the agrivoltaic system has a lower levelized cost of energy (LCOE) and a payback period of 0.039 and 6 years, respectively, which is better than the bifacial (LCOE: 0.046, payback: 7.56 years) and monofacial (LCOE: 0.048, payback: 7.25 years) systems. The Mean Time Between Failure (MTBF) results show that agrivoltaic systems are very reliable, with an MTBF of 40.21 years compared to 32.31 and 31.81 years for monofacial panels and bifacial systems, respectively. The year-round performance of an agrivoltaic system is also comparable to that of a bifacial PV system. The integration of crops not only enhanced energy production but also contributed to the overall reliability of the agrivoltaic system, making it a compelling, and economically advantageous solution for sustainable dual-land-use energy production.

The electricity distribution network is experiencing notable transformations influenced by a cluster of dynamic forces for electrical grid remodelling. One of the technologies supporting this transformation is the transactive energy system (TES). The TES solution can dynamically balance the energy demand and supply of the grid using economic and control techniques. The solution paves the way for a new approach to independent electricity retail markets. This article comprehensively examines and analyzes relevant and recent literature on the technological advancements in TES with a special focus on the concepts, models, metrics, technologies, policies, drawbacks, and future. The review demonstrates the viability of TES as the future of energy distribution to offer a balance between economic growth in terms of provisioning energy at affordable cost, accessibility to energy, and dynamic energy utilization. In addition, sustainable environments promote the implementation and utilization of green energy. Furthermore, the work presents balanced but critical state-of-the-art literature on TES to advance knowledge in the research area. The recommendations include adopting advanced control techniques in delivering effective energy management and cost reduction solutions. Others are experimental implementation for validation; and combining blockchain and Artificial Intelligence technologies to solve identified challenges.

Geothermal energy is a dependable energy source that can catalyze socioeconomic development in developing countries. However, in several countries, geothermal energy sources face community opposition. Therefore, to enable the widespread use of geothermal energy, it is important to address these issues. This study aims to analyze the main factors influencing the community acceptance of geothermal energy projects in East-Africa. In this study, the controversial ’Olkaria IV Geothermal Project’ in Kenya, one of the top geothermal energy producers in the world, was considered as the case study.

A quantitative survey was conducted using a questionnaire for 138 households affected by the project. Furthermore, a stepwise regression model was employed to investigate the determinant factors influencing community acceptance of the project. Fifteen independent variables were included in the model. Seven predictors were selected for the model, namely, “Perception of appropriate mitigation of environmental impacts”, “Isolation during the decision-making process”, “Understanding of socioeconomic benefits”, “Understanding of grievance mechanism”, “Understanding of environmental benefits”, “Perception about environmental impacts”, and “Explanation of grievance mechanism”. Notably, “Isolation during the decision-making process,” “Understanding of environmental benefits,” and “Explanation of grievance mechanism” portrayed a negative relationship with the dependent variable “Community acceptance”.

This study highlights the importance of mitigating environmental impacts, raising awareness about mitigation measures, ensuring inclusive community engagement in the decision-making process (while considering specific cultural customs), and emphasizing the socioeconomic outcomes of the project. In addition, our study highlights the fact that the strong patriarchy of pastoral communities influences the inequality and feeling of isolation in the community, resulting in a communication gap within the community. Moreover, direct socioeconomic and environmental benefits through corporate social responsibility or royalty allowance schemes can also enhance community acceptance. Our study can serve as a framework for future studies that aim to promote the use of geothermal energy and improve the community acceptance of such projects.

The economics of decentralized gasification and centralized steam turbine systems with optimized harvesting, chipping, and transportation costs of unutilized forest biomass were analyzed within the context of the spatial distribution of forest biomass resources using a geographic information system in the Fuji area of Shizuoka Prefecture, Japan. The optimized harvesting, chipping, and transportation costs were 62.50 USD/dry-t for the decentralized system and 65.86 USD/dry-t for the centralized system, confirming that the decentralized system was less expensive than the centralized system. However, electricity production costs for centralized systems, ranging from 0.137 USD/kWh (capacity: 5,000 kW), were found to be more economical than that for decentralized systems, at 0.151–0.165 USD/kWh (capacity: 482 kW), resulting in the higher costs of decentralized systems because of expensive initial investment than that of the centralized system. The rate of heat sold, which lowers the electricity production costs of gasification below those of centralized systems, was 20–40 % for all such plants. To lower the electricity production cost of gasification plants below that of steam-turbine systems, a heat sales rate of approximately 10% and a minimum staff of 0.2 persons for remote operation of the gasification system. Higher heat sales rates further decrease the cost of gasification, making it cheaper than steam-turbine systems even at lower operating rates. To achieve this cost advantage at current low utilization rates, a heat sales rate of 50% and a utilization rate of 90%, based on a unit price of 0.05 USD/kWh, are required.