The influences of temperature on the performance of amorphous silicon (a-Si) solar cells and photovoltaic (PV) systems are extensively studied in the literature. The benefit from thermal annealing effect at a higher temperature than ambient has been demonstrated, which makes a-Si cells a promising material for photovoltaic/thermal (PV/T) system. However, the temperature-dependent performance of a-Si PV/T system in the long term operation has rarely been reported. The temperature effect will be more complicated than that on a single cell or PV system. Particularly, the exergetic efficiency and mechanical behavior of the PV/T system at different temperatures are unknown. To fill the above knowledge gap, two identical a-Si PV/T systems are developed. One operates at a water inlet temperature of 60 °C with an a-Si cell temperature of up to 70 °C. The other operates at an inlet temperature of 30 °C. Long-term outdoor tests from December 2017 to June 2019 have been conducted. Results indicate that the difference in the electrical efficiency between the two systems is 0.47% in the initial stage, and it gradually narrows to only 0.13% over time. The overall exergy efficiency at 60 °C generally exceeds that at 30 °C, which proves the superiority of the a-Si PV/T operating at medium temperature. Besides, the long-term operation at 60 °C has not led to a lower level of reliability.

在文献中已经广泛研究了温度对非晶硅（a-Si）太阳能电池和光伏（PV）系统性能的影响。已经证明了在高于环境温度的温度下热退火效应的好处，这使得a-Si电池成为光伏/热（PV / T）系统的有前途的材料。然而，很少有人报告过a-Si PV / T系统在长期运行中随温度变化的性能。温度影响将比单电池或光伏系统更为复杂。特别地，在不同温度下PV / T系统的能效和机械性能是未知的。为了弥补上述知识空白，开发了两个相同的a-Si PV / T系统。一种在进水温度为60°C的情况下运行，而非晶硅电池的温度最高为70°C。另一个在入口温度30°C下运行。2017年12月至2019年6月进行了长期室外测试。结果表明，两个系统之间的电气效率差异在初始阶段为0.47％，随着时间的推移逐渐缩小到仅0.13％。60°C时的总火用效率通常超过30°C时的总效率，这证明了a-Si PV / T在中等温度下工作的优越性。此外，在60°C下长期运行不会降低可靠性。60°C时的总火用效率通常超过30°C时的总效率，这证明了a-Si PV / T在中等温度下工作的优越性。此外，在60°C下长期运行不会降低可靠性。60°C时的总火用效率通常超过30°C时的总效率，这证明了a-Si PV / T在中等温度下工作的优越性。此外，在60°C下长期运行不会降低可靠性。