The rising efficiency of solar power has been a huge boon to stopping global warming. Unfortunately, air pollution may prevent solar from being effective in regions that need clean energy the most.

Air pollution in China blocks the path to solar

It’s no secret that China has some of the most polluted skies in the world. In China’s urban regions, you can hardly see the sun through the heavily polluted skies.

The dense layer of smoke and aerosols in China’s sky prevents a lot of sunlight from ever reaching solar panels. Fine dust and ash in the air scatter sun-rays, causing less light to hit solar panels on the ground. Nature published a study that found that if China’s pollution was reduced to 1960’s levels, solar panels would’ve produced about 12 percent more energy in 2016.

In certain areas of China, pollution could reduce sunlight exposure by over 30%. In these areas, many of which are polluted due to reliance on coal, solar power may not be economically feasible. Paradoxically, cities that are most reliant on coal have the hardest time switching to solar due to air pollution.

India suffers significant solar energy losses to air pollution

India, which is home to nine out of ten of the world’s most polluted cities, also has an enormous problem with solar efficiency. A 2017 report in the Environmental Science and Technology Letters found that air pollution reduced solar energy production by between 17 and 25 percent across India, China, and the Arabian Peninsula.

India’s solar industry suffers the most from this pollution. The country loses over 25% of its solar energy to air pollution. To put it into perspective, that’s over a gigawatt of solar-generated electricity. Given that India has pledged to double solar capacity by 2040, losing 25% of that power is an enormous economic loss.

Cities and villages in India that rely on solar power are especially at risk of air pollution. Fluctuating air quality could greatly reduce the energy security of many Indian communities.

Economic losses have motivated action

On the bright side, the economic losses caused by air pollution have galvanized China and India to tackle the problem.

Beijing started sweeping efforts to reduce pollution in 2013. Since then, China has also announced plans to both triple solar capacity by 2030 as well as lower pollution levels to 1960s levels. India has also announced a 5-year plan to reduce air pollution by 20 to 30 percent in it’s 102 most polluted cities.

However, efforts to stop air pollution will take many years. Many people also criticize China and India for setting unrealistic pollution goals without concrete action plans. In the meantime, heavy government subsidies will have to keep solar affordable in polluted cities.

One can only hope political will stays strong enough to keep support for solar going until clearer skies can make solar power more affordable.