In order to evaluate the feasibility and performance of liquid lead-bismuth eutectic as the heat transfer fluid for thermocline heat storage tanks in solar power systems, we conducted an effect ...evaluation of filling medium parameters on the integrated operating and mechanical performances of a thermocline tank using liquid lead-bismuth eutectic using the computational fluid dynamics simulation method. Four parameters were evaluated: the porosity, thermal conductivity, specific heat capacity, and equivalent diameter of the filling medium. The results show that the liquid lead-bismuth eutectic tank operated stably. The total charging and total discharging durations were 5.7 h and 5.3 h, respectively, and the discharging efficiency was 91.94%. The effect evaluation results reveal that the discharging thermocline thickness of the liquid heavy metal tank can be decreased by increasing the specific heat capacity of the filling particles, or by decreasing the porosity, thermal conductivity, and equivalent diameter of the filling medium. The total discharging quantity of the tank increased from 2.19 × 1010 J to 3.34 × 1010 J when the specific heat capacity of the filling particles increased from 610.0 J/(kg∙K) to 1010.0 J/(kg∙K), while the other three filling medium parameters had no obvious effect on the total discharging quantity of the tank. The mechanical performance of the tank wall could be improved by decreasing any one of the four evaluated parameters of the filling medium. The results of this paper may serve as a reference for the design of actual liquid heavy metal heat storage tanks in solar power plants.
Load frequency control (LFC) serves as a crucial component of automatic generation control in renewable energy power systems. Its primary objective is to maintain a balance between the output power ...of generators and the load demand, thereby ensuring system frequency stability. However, integrating renewable energy sources into power systems brings forth several challenges, such as low power quality and poor system stability due to their uncontrollable nature. To enhance the response speed, stability, and disturbance rejection capabilities of LFC, a novel fractional-order active disturbance rejection controller (NFOADRC) based on an improved marine predator algorithm (IMPA) has been designed in this paper. By leveraging the wide frequency-response range and non-local memory of NFOADRC, a more precise prediction and compensation of rapid oscillations in the system can be achieved. Additionally, the IMPA can be utilized for efficient parameter tuning, enabling a more accurate adjustment of the controller. Subsequently, the combined application of these approaches can be applied to two-area interconnected power systems with a solar thermal power plant (STPP) and a five-area interconnected power system including a wind turbine generator (WTG), photovoltaic (PV) cells, hydro turbine, and gas turbine. The simulation results confirm that the proposed control strategy effectively minimizes the undershoot and overshoot of frequency deviation in the power system. It achieves a faster stabilization of the load frequency, leading to enhanced power quality.
Sustainable green campus in NEPAL: 3E analysis Yadav, Bharosh Kumar; Rauniyar, Pankaj Kumar; Sudhakar, K ...
International journal of low carbon technologies,
05/2021, Letnik:
16, Številka:
2
Journal Article
Recenzirano
Odprti dostop
ABSTRACT
In today’s world, where global warming is one of the greatest human challenges, sustainable energy generation is becoming increasingly relevant. The use of green and clean energy sources is ...the best way to minimize CO2, CO, NOX and other emissions of conventional energy usage. Solar photovoltaic (PV) systems are more beneficial and an exciting application to set up an eco-friendly green educational campus. In this regard, the potential sites within Tribhuvan University, Institute of Engineering, Purwanchal Campus, Dharan city, Nepal are analysed for grid-tied solar PV power plant installation to meet the 100% energy demand of the campus using energy, economic and environment-friendly analysis. The daily, monthly and annual load and solar irradiance data of past years of the campus have been analysed to estimate the solar PV plant’s capacity and system performance using PVSYST V7.0 software analysis tools .The simulation results show that 110 kWp of solar PV power plant will be sufficient for the entire campus to qualify for the first fully green-powered campus in Nepal, which corresponds to fulfill 66.4 MWh/year daytime energy demand out of total 161 MWh/year energy consumption of the campus with a capacity to generate a total of 181.5 MWh/year energy from the designed solar PV system. The result also shows that 115.1 MWh/year of surplus energy produced from the PV power plant can be injected into the utility grid to yield considerable savings in utility cost. On the basis of these results, campus authorities and stakeholders may commit to investing and implementing of this project to ensure that the campus is completely green.
In this paper the German congestion management regime is analyzed and future congestion management costs are assessed given a higher share of intermittent renewable generation. In this context, ...cost-based re-dispatching of power plants and technical flexibility through topology optimization are considered as market-based and technical congestion management methods. To replicate the current market regime in Germany a two-step procedure is chosen consisting of a transactional spot market model and a congestion management model. This uniform pricing model is compared to a nodal pricing regime. The results show that currently congestion can mainly be managed by re-dispatching power plants and optimizing the network topology. However, congestion management costs tend to increase significantly in future years if the developments of transmission as well as generation infrastructure diverge. It is concluded that there is a need for improving the current congestion management regime to achieve an efficient longterm development of the German electricity system.
Abstract
Developing nations have a critical need to increase electricity supply. Sudan has much unrealized potential for generating solar energy, particularly in the northern region. This research ...study focuses on designing a 1-GW solar power station in northern Sudan using the PVsyst7.0 software program. To determine the appropriate location for the solar-energy station, 14 criteria were evaluated. This process is generic and suitable for use in any other country. The method for conducting cash-flow estimates and return on investment is illustrated in the economic evaluation. The city of Dongola, the capital of the northern state, was selected because of its high annual irradiance on a horizontal surface at ~2333.2 kWh/m2. The simulation results show that the annual optimum tilt angle of inclination for photovoltaic (PV) modules is 30°, the energy production is 1 979 259 MWh/yr and the average annual performance rate is 0.810. In addition, the electric power consumption per capita in Sudan is 269 kWh/yr, so the proposed solar power plant with 1 979 259 MWh/yr can provide energy to 7.4 million people per year annually and reduce carbon emissions by ~18 million tons of carbon dioxide per year. Economic calculations show that the levelized cost of electricity (LCOE) is $0.06/kWh, the discounted payback period is ~11 years and the net present value is $635 291 000. As a result, the proposed grid-connected PV solar plant is considered economically, technically and environmentally feasible in Sudan.
Agrophotovoltaic (APV) systems produce both solar energy and crops, so they are considered a sustainable alternative to traditional solar power plants, which can potentially destroy farmlands. ...However, it is challenging to diffuse APV systems because of their high installation and operating costs. Thus, to resolve the issue by maximizing the productivity and profits of an APV system, this study aims to propose a mobile-phone-based decision support system (DSS) for a supply chain network design for APV systems in South Korea using satellite imagery incorporating geographic information system (GIS) data. Particularly, polynomial regression models estimating annual corn (Zea mays) yields and the predicted generation of electricity were developed and integrated with the proposed DSS. Field experiment data provided by the APV system at Jeollanamdo Agricultural Research and Extension Services in South Korea were utilized. Two photovoltaic (PV) module types (mono-facial and bi-facial) and three different shading ratios for APV systems (21.3%, 25.6%, and 32.0%) were considered design factors for APV systems. An optimal network structure of 6 candidate APV systems and 15 agricultural markets was devised using the generalized reduced gradient (GRG) method. The profits of the six candidate APV systems are mainly affected by the transportation costs to the markets and the policy of the electricity selling prices. As a result, the proposed supply chain design framework successfully identifies an APV system network with maximum profits from crop production as well as electricity generation.
The main purpose of this study is to develop a cost-effective photovoltaic module array (PVMA) fault detection system. The system installs a fault detection module in the junction box at the back of ...each photovoltaic module (PVM), connects it to the Wi-Fi on the case site, and transfers data and information to the server for data analysis. The PVM outputs the voltage to the isolated DC-DC power module as the power supply of the overall circuits. The fault detection module sends data to the message queuing telemetry transport (MQTT) broker through the protocol in MQTT. As for the server host end, the visualization IoT development tool Node-RED is set up to display complex data sent by the fault detection module by means of data visualization. At the same time, it is linked to the open source time series database (OSTSDB) to process time series data. Finally, the results of the PVM are instantly sent to the maintenance personnel through an exception alert notification in order to inform the maintenance personnel to quickly rule out the failure. As the developed fault detection system hardware is more cost-effective than existing detection systems, the cost-effectiveness is favorable for mass production with market competitiveness.
Adopting rooftop solar PV systems in various domestic and non-domestic sectors (including commercial, industrial, and agricultural) exhibits their commitment to green energy ventures. This study ...intends to evaluate the effectiveness of a grid-connected solar system that has been installed so far: a 6.9 MW
p
photovoltaic (PV) system implemented at University Tun Hussein Onn (UTHM) in Batu Pahat, Johor. This green energy system was installed as a part of the Self-Consumption (SELCO) program utilizing a Supply Agreement for Renewable Energy (SARE) contract. To assess the mounted energy system's efficiency, performance monitoring was carried out between December 2021 and November 2022. By evaluating the enactment of the 6.9 MW
p
solar system at UTHM, this present work has attempted to compile the achievement of implementation of self-consumption in terms of performance analysis and financial benefits to consumer. Based on International Electrotechnical Commission (IEC) 61724 standard, this study also investigates several performance characteristics of the PV system, such as final yield, clearness index (CI), array yield, PV module efficiency, inverter efficiency, reference yield, and capacity factor (CF) performance ratio (PR). Moreover, an assessment of Carbon Dioxide (
CO
2
)
avoidance was also conducted to quantify the amount of
CO
2
reduction achieved. In addition, the self-consumption ratio and self-sufficiency ratio pattern for solar power plant in UTHM has been assessed. The monthly clearness index at the project location from December 2021 to November 2022 ranges from 0.63 to 0.66. The PV system was monitored throughout this time and generated 8529 MWh of energy. The installed PV system has shown an efficiency of 11.86%, a final yield of 108.28%, and a PR of 0.78, respectively. Further, the installed 6.9 MW
p
PV system at UTHM will cut
CO
2
emissions by 5450 tons annually. The 6.9 MWp solar PV system is also estimated to reduce 25.1 RM mil in 25 years. Making the system larger to 6.9 MW
p
would reduce the consumption from the grid during the week, makes it possible to achieve self-consumption levels of up to 100% and self-sufficiency of this solar plant is relatively low ranges from 22 to 35%. The research finding bridges the gap between policy makers, investors, and the public regarding acceptance of the large-scale Self-Consumption (SELCO) and strengthen the strategic collaborations between solar service provider and educational bodies to support of the government’s agenda to achieve carbon emission intensity reduction in Malaysia.
Graphical Abstract
Articles Highlights
The study site’s yearly average solar radiation of 133.83 kWh/m
2
indicates the area’s significant potential for solar energy harvesting.
Technical performance analysis showed that the site is very favorable for the deployment of solar PV systems, with an annual average performance ratio of 78% derived from the collected data.
The solar PV system has considerable environmental benefits, with an estimated annual decrease of 5450 tons of CO
2
emissions.
This paper develops a model, introduced in software, namely Multi-Criteria Decision-Making Model (MCDMM). The model helps decision makers selecting the most suitable alternative based on the customer ...requirements and preferences. Analytic Hierarchy Process (AHP) and Fuzzy Technique for Order of Preference by Similarity to Ideal Solution (Fuzzy TOPSIS) form a package that covers most available data types in construction projects. In MCDMM, AHP produces criteria relative weights according to their influence on the discussed problem, while Fuzzy TOPSIS is applied to rank the available alternatives. The model consists of two modules, first one uses AHP only to deal with precise, qualitative alongside quantitative data, while the other module combines AHP with Fuzzy TOPSIS due to the importance of linguistic variables to cover undocumented data. MCDMM is verified using two real case studies. The model is applied to a real case project for constructing solar power plants at Saudi Arabia. A decision required to select the most suitable surveying technique for producing Digital Terrain Model (DTM) among four alternatives (Total Station, Remote Sensing, Photogrammetry, and Global Positioning Systems). This issue is studied and key points are identified for prioritizing among them. Total Station is selected based on the model results.
Thermal Power Plants (ThPP), along with transport facilities, are the major sources for industrial emissions of carbon dioxide (CO 2 ) believed to be responsible for the greenhouse effect leading to ...overheating of the lower atmosphere. In the opinion of many scientists, there is a threshold value of the average atmospheric temperature exceeding, which entails the potential for the development of irreversible processes threatening the existence of humankind. To avoid this danger, governments in nearly 200 countries have chosen voluntarily to reach net-zero CO 2 emissions by 2050. Renewable Energy Sources (RES), including wind and solar power plants, have been selected as substitutes for ThPPs. However, energy systems based on RES only need to be multiply redundant in terms of installed capacity due to their efficiency being heavily dependent on daily, seasonal and weather factors, leave alone the scale of the required material resources (metals, polymers, concrete, glass, etc.). The major drawback of such energy systems is, however, the RES common-cause failure, e.g., in the event of a global volcanic eruption, when no energy-security requirement can be met to provide energy for satisfying the most vital needs. A need is fully evident for furnishing such energy system with another power source to be not dependent on the event that has caused the mass RES failure. With the net-zero-carbon requirement taken into account, Nuclear Power (NP) appears to be the best option in this respect. Modern NP does not however fully suits this role due to its inherent drawbacks (limited fuel resources, pending Spent Nuclear Fuel (SNF) and RadioActive Wastes (RAW) handling and nuclear-material nonproliferation issues). A potential solution to these drawbacks is a two-component NP technology in a closed nuclear-fuel cycle currently in the process of development. In Russia, where the greatest progress has been achieved in this field of development, under construction is a pilot and demonstration energy complex with the BREST-OD-300 nuclear unit expected to be started up in 2026–2027. Another promising designs to be developed are Small Modular Reactors (SMRs) / Small Nuclear Power Plants (SNPPs).