A lot can keep solar panels from generating electricity, from cloud cover blocking the sun to simply being nighttime. But according to recent research, one of the biggest obstacles facing solar farms is smog and haze from air pollution.
Urban haze is a multifaceted threat. Foremost a major health hazard, it also affects the passage of light through the lower atmosphere.
In their paper, they present a study addressing the impact of haze on the performance of photovoltaic installations in cities. Using long-term, high resolution field data from Delhi and Singapore they derive an empirical relation between reduction in insolation and fine particulate matter (PM2.5) concentration.
Their approach enables a straightforward way to estimate air pollution related losses to photovoltaic power generation anywhere on the planet. For Delhi, they find that insolation received by silicon PV panels was reduced by 11.5% ± 1.5% or 200 kWh m−2 per year between 2016 and 2017 due to air pollution. They extended this analysis to 16 more cities around the planet and estimated insolation reductions ranging from 2.0% (Singapore) to 9.1% (Beijing). Using spectrum data from Singapore, they projected how other photovoltaic technologies would be affected and found an additional reduction compared to silicon of between 23% relative for GaAs and 42% for a 1.64 eV perovskite material.
Considering current installation targets and local prices for electricity, they project that annual losses in revenue from photovoltaic installations could exceed 20 million USD for Delhi alone, indicating that annual economic damage from air pollution to photovoltaic site operators and investors worldwide could be billions of dollars.