基于太阳能分频利用的光伏/光热综合发电系统热力学分析

Thermodynamic Analysis of a Photovoltaic/Photothermal Integrated Power Generation System Based on Solar Energy Spectrum Utilization

通过对太阳能聚光投入辐射进行分频,建立光伏与光热驱动有机朗肯循环综合供电系统。在冷却背板温度100℃的限制下,对该系统进行热力学分析,筛选了适宜的循环工质,获得了有机朗肯循环(ORC)系统优化的蒸发温度。结果表明:isobutene作为光伏系统的冷却工质和ORC系统的循环工质时系统效率最高,分频技术将冷却背板散热负荷转移至集热器,可降低光伏板的散热需求,从而降低循环工质质量流量,对提高系统发电能力有积极作用,该系统可将单纯光伏发电效率提高9百分点;同时,分频效率和太阳能电池吸收波段对综合供电系统的总效率影响较大。

By dividing the incident solar spectrum into bands,an integrated photovoltaic(PV)and photothermal(PT)driven organic Rankine cycle(ORC)was established.Thermodynamic analysis of the system was conducted under the temperature limit of 100℃for the cooling panel,to identify suitable working fluids for the ORC system and optimize the evaporation temperature.Results show that isobutene as the cooling fluid for the photovoltaic system and the working fluid for the ORC system,the highest system efficiency can be achieved.Frequency division technology transfers the heat dissipation load of the cooling panel to the collector,which can reduce the cooling demand of the photovoltaic panel and thus reduce the mass flow rate of the working fluid.It has a positive effect on improving the system's power generation capacity,and can enhance the efficiency of pure photovoltaic electricity generation by 9%.Additionally,frequency division efficiency and the absorption band of solar cells significantly impact the overall efficiency of the integrated power supply system.