Utility-scale solar PV performance enhancements through system-level modifications

Sci Rep. 2020 Jun 29;10(1):10505. doi: 10.1038/s41598-020-66347-5.

Abstract

Performance of solar PV diminishes with the increase in temperature of the solar modules. Therefore, to further facilitate the reduction in cost of photovoltaic energy, new approaches to limit module temperature increase in natural ambient conditions should be explored. Thus far only approaches based at the individual panel level have been investigated, while the more complex, systems approach remains unexplored. Here, we perform the first wind tunnel scaled solar farm experiments to investigate the potential for temperature reduction through system-level flow enhancement. The percentage of solar irradiance converted into electric power depends upon module efficiency, typically less than 20%. The remaining 80% of solar irradiance is converted into heat, and thus improved heat removal becomes an important factor in increasing performance. Here, We investigate the impact of module inclination on system-level flow and the convective heat transfer coefficient. Results indicate that significant changes in the convective heat transfer coefficient are possible, based on wind direction, wind speed, and module inclination. We show that 30-45% increases in convection are possible through an array-flow informed approach to layout design, leading to a potential overall power increase of ~5% and decrease of solar panel degradation by +0.3%/year. The proposed method promises to augment performance without abandoning current PV panel designs, allowing for practical adoption into the existing industry. Previous models demonstrating the sensitivity to convection are validated through the wind tunnel results, and a new conceptual framework is provided that can lead to new means of solar PV array optimization.