一种双层槽式聚光晶硅光伏-光热甲醇裂解发电系统探析

Exploration of a Power Generation System Coupling Si PV and Photothermal Methanol Decomposition by Double-layer Parabolic Trough Concentrator

利用分频技术实现太阳能全光谱高效利用是当前太阳能研究领域的热点,本文基于“先分光,后聚光”原理的双层槽式聚光镜,探析了聚光晶硅光伏-光热甲醇裂解互补发电系统的全光谱发电性能。开展了运行参数对系统性能影响的分析,发现在不同辐照条件、不同压力下,具有相应的最佳甲醇流量,使得光热化学转化效率最高。在辐照度500 W·m;的条件下对设计参数光伏电池聚光比和截止波长进行了优化,系统全光谱发电效率随两个参数增加均呈现先升高后降低的规律,在聚光比为9.5,截止波长为300 nm时取得最优值。结合青海德令哈地区气象参数分析了该系统全年发电性能,结果表明其太阳能全光谱年均发电效率可达25.85%。本研究为提高太阳能全光谱发电效率提供了一种新的方法。

Utilizing spectral splitting technology to realize the efficient utilization of solar energy in full-spectrum is a hot spot. In this paper, based on the double-layer parabolic trough concentrator of“Splitting Sunlight Firstly and then Concentrating”, the full-spectrum power generation performance of concentrating c-Si PV-photothermal methanol decomposition system is explored. The influence of operating parameters on system performance is analyzed, and it is found that under different irradiation conditions and pressures, there is a corresponding optimal methanol flow rate, which makes the photothermal chemical conversion efficiency the highest. Then two design parameters,the concentrating ratio of PV cell and the cut-off wavelength, are optimized under the condition of irradiation for 500 W·m;. The full-spectrum power generation efficiency of the system initially increases and then decreases as rising these two parameters, and the optimal value is obtained when the concentrating ratio is 9.5 and the cut-off wavelength is 300 nm. Finally, according to the meteorological parameters in Delingha, Qinghai Province, the annual power generation performance of the system is analyzed. The results show that the annual full-spectrum power generation efficiency of the hybrid system can reach 25.85%. As a result, this study provides a new method for improving the efficiency of solar full-spectrum power generation.