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- 实验方案
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Effect of the Orientation Schemes of the Energy Collection Element on the Optical Performance of a Parabolic Trough Concentrating Collector
摘要： While the circular shape is currently the proven optimum design of the energy collection element (ECE) of a parabolic trough collector, that is yet to be confirmed for parabolic trough concentrating collectors (PTCCs) like trough concentrating photovoltaic collectors and hybrid photovoltaic/thermal collectors. Orientation scheme of the ECE is expected to have significant effect on the optical performance including the irradiance distribution around the ECE and the optical efficiency, and therefore, on the overall energy performance of the PTCC. However, little progress addressing this issue has been reported in the literature. In this study, a thorough investigation has been conducted to determine the effect of the orientation schemes of ECE on the optical performance of a PTCC applying a state-of-the-art Monte Carlo ray tracing (MCRT) technique. The orientation schemes considered are a flat rectangular target and a hollow circular, semi-circular, triangular, inverted triangular, rectangular and rectangle on semi-circle (RSc). The effect of ECE defocus, Sun tracking error and trough rim angle on the optical performance is also investigated. The MCRT study reveals that the ECE orientation schemes with a curved surface at the trough end showed much higher optical efficiency than those with a linear surface under ideal conditions. ECEs among the linear surface group, the inverted triangular orientation exhibited the highest optical efficiency, whereas the flat and triangular ones exhibited the lowest optical efficiency, and the rectangular one was in between them. In the event of defocus and tracking errors, a significant portion of the concentrated light was observed to be intercepted by the surfaces of the rectangular and RSc ECEs that are perpendicular to the trough aperture. This is an extended version of a published work by the current authors, which will help to design an optically efficient ECE for a parabolic trough concentrating collector.
关键词： optical efficiency,optical performance,concentrating solar power,parabolic trough concentrating collector,irradiance distribution,Monte Carlo ray tracing
更新于2025-09-23 15:23:52
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Analysis of optical and thermal factors’ effects on the transient performance of parabolic trough solar collectors
摘要： Solar resources are inherently unsteady and their energy density on the earth is low. Thereby, when the solar energy is converted into thermal energy through concentrating the sunlight, how to predict the transient performance of parabolic trough solar collectors under the operating conditions is necessary for the steady useful output and the efficient use of the energy. So this paper describes a mathematical model of the transient thermal behaviors of parabolic trough solar collectors. Then, to validate this transient model, its numerical results are compared with the experimental data. These data were collected from a utility-scale loop of parabolic trough solar collectors. The comparison between the model predictions and the experimental data shows a consistent and reasonable agreement. Furthermore, the primary interest of this study is to determine how the temperature distributions of the absorber, the glass envelope and the heat transfer fluid evolve from initial conditions with specified optical and thermal parameters. Thus, this model is used to carry out parametric studies to make analyses of essential impact factors on transient behaviors of parabolic trough solar collectors. These factors include the temperature of the heat transfer fluid at the inlet, the initial conditions, and the optical efficiency. Moreover, this model has the function of continuous adjustment of the flow rate to satisfy the requirement of the temperature of the heat transfer fluid at the outlet according to varying boundary conditions. Hence, another analysis is performed to investigate transient processes when the flow rate is continuously adjusted at various DNI ramp rates.
关键词： Concentrating solar power,Transient model,Parabolic trough solar collector,Solar heating and cooling
更新于2025-09-23 15:23:52
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Radiative energy and exergy analyses of spectrally-selective surfaces for CSP systems
摘要： This work presents a new methodology for calculations of spectral radiative energy and radiative exergy to evaluate the performances of concentrated solar power (CSP) systems. Spectral radiative properties and the operating temperature of selective surfaces, along with the temperature of the environment, are taken into account in analyses. The fundamental expressions needed for the spectral radiative energy and exergy analyses are introduced first. Then, the two approaches are used to assess the spectral performance of five selective coatings. The spectral analysis is performed in the wavelength range of 250 nm to 20,000 nm, while thermal analysis is carried out for the temperature range of 325 K to 800 K. NREL 6A coating was found to result in the highest radiative energy and radiative exergy for both efficiencies and gains, and for the best thermal stability compared to the other coatings.
关键词： selective coating,spectral radiative energy analysis,concentrating solar power systems,spectral radiative exergy analysis
更新于2025-09-23 15:23:52
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[IEEE 2018 2nd IEEE Conference on Energy Internet and Energy System Integration (EI2) - Beijing, China (2018.10.20-2018.10.22)] 2018 2nd IEEE Conference on Energy Internet and Energy System Integration (EI2) - Concentrating Solar Power Station Optimal Operation Model
摘要： With the improvement of energy structure, large scale grid connection of renewable energy, as a new technology for absorbing solar energy, concentrating solar power generation uses a thermal storage system to make it a schedulable resource without increasing the uncertainty of the system. This paper considers the energy transfer process and the thermal energy conversion efficiency among the concentrating solar modules, and constructs their basic operation models respectively. Through the design of different operating modes, the examples are simulated. The values of key parameters are taken into account to optimize the operation results. The impact of the analysis shows that concentrating solar power plants have certain advantages in dealing with solar energy uncertainty, prolonging production cycles, improving the utilization efficiency of heat storage tanks, and economic efficiency.
关键词： Concentrating solar power,renewable energy,thermal energy storage,optimal operation
更新于2025-09-23 15:22:29
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[Energy, Environment, and Sustainability] Advances in Solar Energy Research || Supercritical Carbon Dioxide Solar Thermal Power Generation—Overview of the Technology and Microchannel Receiver Development
摘要： The supercritical carbon dioxide (sCO2) power cycle is being considered for solar thermal central receiver systems in the United States. The cycle lends to increased high-temperature input that is expected of the next-generation concentrating solar thermal power (CSP) systems. Power block efficiencies of about 50% can be achieved for recompression cycles at an input temperature of approximately 720 °C. Additionally, the power block is compact and less complex, raising the possibility of using thermal-storage-coupled CSP sCO2 technologies for modular (*100 MW) peak-load power plants. Three pathways toward providing solar thermal input to the sCO2 cycle have been proposed by various research groups—the molten salt receiver pathway, the solid particle receiver pathway, and the gas-phase receiver pathway. The first two technologies have the advantage of sensible thermal storage within the solid/fluid medium passing through the receiver. In the gas receiver pathway, there is a need for coupling a sensible or latent heat storage technology. Several key technologies are needed to enable the realization of the sCO2 solar thermal technology, key among them being the receiver and thermal storage. In this chapter, some of the key gas-phase receiver technologies are discussed. The group’s past and recent work on the development of microchannel solar thermal receivers for sCO2 is emphasized.
关键词： Solar thermal,Efficiency,Supercritical carbon dioxide,Microchannel,Receiver,Concentrating solar power
更新于2025-09-23 15:21:21
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Feasibility Analysis of Nanostructured Planar Focusing Collectors for Concentrating Solar Power Applications
摘要： Concentrating solar power (CSP) technology is an attractive approach to harvesting solar energy. Unlike photovoltaic (PV) technology, thermal storage is used in lieu of batteries for electricity generation. However, the cost of current collection optics in a CSP plant hampers commercial competitiveness with PVs and natural gas. The use of a planar focusing collector (PFC) could help reduce cost of materials, installation, and maintenance. We present two candidate PFC designs, one based on metasurfaces and the other a Fresnel-like model. We feed each design through the entire system process—design, fabrication, scalability, and techno-economic feasibility—and discuss the challenges met at each stage. Two-photon and nanoimprint lithography are used to make PFC molds and replicas, respectively. We find that the annual optical efficiency for the Fresnel-based PFC is ~40%--higher than the current 30% target for natural gas, thereby suggesting potential economic advantages in the market of industrial process heat.
关键词： Metasurface,Two-Photon Lithography,Concentrating Solar Power (CSP),Planar Focusing Collector (PFC),Nanoimprint Lithography
更新于2025-09-23 15:21:01
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Concentrating photovoltaic retrofit for existing parabolic trough solar collectors: Design, experiments, and levelized cost of electricity
摘要： Photovoltaics and concentrating solar thermal power are two ways for generating electricity from sunlight, albeit through different methods. Parabolic trough style powerplants represent 3.6 GW of electricity production, but many of these plants are aging and being replaced with photovoltaics. An alternative option that could be employed to leverage the sunk capital cost associated with the primary optics would be the design of a pure photovoltaic retrofit working within the existing plant architecture. Here, a secondary optical concentrator is designed to use the existing primary optics of a parabolic trough type solar thermal powerplant. The design is a v-shaped secondary concentrator resulting in a predicted concentration ratio on a 20 mm wide target of 94. The concentrating photovoltaic receiver for retrofit of an RP-3 based parabolic trough has been constructed using multi-junction concentrator photovoltaic cells and experimentally demonstrated here for the first time. Calculated performance of the cells based on cell specifications should result in 31% efficiency at 85 °C. On-sun efficiencies were measured at an average value of 21% with operational temperatures between 55 and 120 °C. Levelized cost of electricity calculations predict the system to have the potential to be below 7￠/kWh based on predicted efficiencies and 13￠/kWh based on the measured values at cell costs of $5/cm2.
关键词： Concentrating solar power (CSP),Solar energy,Retrofit,Photovoltaic (PV)
更新于2025-09-23 15:19:57
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The Knowledge Mapping of Concentrating Solar Power Development Based on Literature Analysis Technology
摘要： Decreasing the levelized cost of renewable energy and improving the stability of power systems are the key requirements for realizing the sustainable growth of power production capacity. Concentrating solar power (CSP) technology with thermal energy storage can overcome the intermittent and unstable nature of solar energy, and its development is of great significance for the sustainable development of human society. In this paper, topic discovery and clustering were studied using bibliometric, social network analysis and information visualization technology based on the Web of Science database (SCI-Expanded) and the incoPat global patent database. The technology searched for papers and patents related to CSP technology to reveal the development trends of CSP technology and provide the references for related technical layout and hot spot tracking. The results show that the global output of CSP technology papers has continued to grow steadily, whereas the number of patent applications showed a significant downtrend. CSP technology, which is at the initial stage of commercialization, still needs technological breakthroughs. Technological innovation that integrates thermal engineering, control engineering, physics, chemistry, materials, and other disciplines may become an effective path for CSP technology development in the future. CSP technology research shows increasing research and development trends in high-temperature receivers, phase-change thermal energy storage, the overall performance of thermal power generation systems, and a development trend from a single technology to multi-energy complementary systems.
关键词： domain development trend,concentrating solar power,renewable energy,bibliometrics,knowledge mapping
更新于2025-09-23 15:19:57
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Risk assessment in a central concentrating solar power plant
摘要： In this paper, optimal scheduling of a central concentrating solar power (CSP) plant which is one of the most promising technologies in the solar energy is investigated in the presence of different uncertainties. Thermal energy storage is integrated with the CSP plant in order to allow the plant to be independent from the instantaneous solar radiation. In order to model different uncertainty such as power market price and solar irradiation, a new hybrid information gap decision theory (IGDT)-stochastic method is introduced which is a mixed-integer linear programming method and presents more reliable results in a suitable computation time. In the proposed method the uncertainty of the solar irradiation is modeled by IGDT method while power market price uncertainty is considered by a set of fifty scenarios. Three different strategies as risk-averse, risk-neutral and risk-taker are introduced to analyze the operation of the CSP plant. In the risk-neutral strategy, obtained profit is equal to $3895 which is reduced in the risk-averse strategy by increasing robustness value indicating increased uncertainty of the solar irradiation. In the risk-taker strategy, the CSP operating profit will be equal to $4245 by 15% of increase in solar radiation, comparing with the risk-neutral case shows almost 8.2% increase in profit.
关键词： Information gap decision theory (IGDT),Solar thermal energy storage,Stochastic optimization,Concentrating solar power (CSP) plant
更新于2025-09-19 17:15:36
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Dynamic analysis of a concentrating photovoltaic/concentrating solar power (CPV/CSP) hybrid system
摘要： Concentrating photovoltaic/concentrating solar power (CPV/CSP) systems suffer from varying irradiation and extreme working conditions. In this study, a dynamic physical model is developed for the CPV/CSP hybrid system to analyze the dynamic responses of several key parameters, such as the solar radiation saltation or linear variation to represent the typical weather variations. The results show that the hybrid system could rapidly reach the steady state in less than about 53 s after the solar radiation saltation increases or decreases by 10%. The response time reflects that the thermal hysteresis of the hybrid system is mainly determined by varying the outlet temperature of R134a from the solar thermal receiver. Meanwhile, when the solar radiation changes linearly, a lower gradient is beneficial to remit the thermal hysteresis of the hybrid system and improve the thermal stability, and the parameters could be treated as the steady state values with a gradient of less than 0.2 W m–2 s–1. Afterward, the quasi-steady state model was used to analyze the all-day dynamic performance of the hybrid system. It shows that the power output and the flow rate are directly related to the direct normal irradiance (DNI), while the outlet temperature of R134a vapor could be almost constant except for the starting and stopping periods.
关键词： solar radiation disturbance,concentrating solar power,dynamic performance,concentrating photovoltaic,transient simulation
更新于2025-09-19 17:13:59