Effectiveness of full spectrum light soaking on solar cell degradation analysis

This study examined the effect of UV-spectrum light soaking on solar cell degradation tests. An indoor light soaking test was evaluated over three different spectral ranges: “UV only”, “UV blocked” and “Full spectrum”. a-Si:H and poly-crystalline silicon solar cell technologies were studied by light soaking tests with the same optical filter configurations. V measurement results demonstrated that “UV only” irradiated solar cells exhibited the smallest output power degradation, which was only half of a percent variation compared with the full spectrum light soaking case. Using a filter that excluded the effect of the UV spectral range on light soaking, the “UV blocked” case also exhibited a significant output power degradation of the solar cells. A comparative analysis of the solar cell response, based on the I–V characteristics and the diode ideality factor under these different light soaking spectra, demonstrated the importance of the full spectrum light soaking test in the evaluation of the long-term performance of solar cells.