(TOI)
India is making a big push for solar energy, with power capacity expected to double this year. But some of the gains, especially in north India, could be offset by a growing problem: air pollution. A new study, the first of its kind in India and one of a handful globally, has found that dust and particulate matter (PM) may be reducing the energy yield of solar power systems in north India by 17-25 per cent annually.
Half this reduction comes from dust and particles deposited on the surface of solar panels and which forms a physical barrier to light entry, said Duke University professor Mike Bergin, who led the study. Researchers allowed panels to accumulate dust for a month. Most importantly, half the decline in energy yield came from ambient pollution–haze that reduces the amount of sunlight reaching the ground, a phenomenon known as solar dimming. “This study thus shows that improving air quality can lead to a big improvement in solar energy yield,” said Bergin. “Cleaning panels is not enough.”