11 March, 2021
Aside from the conversion of sunlight to electricity, all solar cells generate and dissipate heat, thereby increasing the module temperature above the environment temperature. This can increase module and system costs by lowering its electrical output and shortening the module lifetime. We assess the economic impact of thermal effects on PV systems by establishing a temperature-dependent levelized cost of energy (LCOE) model. Using this model, we introduce an equivalent ratio, γ (with the unit of absolute efficiency %/K), as a new metric that quantitatively translates the LCOE gain obtained by reducing the module temperature to an equivalent absolute power conversion efficiency (PCE) increase. γ, most importantly, demonstrates that once the PCE approaches a practical upper limit, work on the control and mitigation of the module temperature can be equally or even more significant than costly marginal gains in PCE.