China has the largest solar energy production capacity in the world. But a new study by European and Chinese scientists shows that capacity is greatly hindered by air pollution (Nat. Energy 2019, DOI: 10.1038/s41560-019-0412-4). As of 2017, China has the capacity to produce 130 GW of solar photovoltaic electricity, and it plans to increase that to 400 GW by 2030. However, human-caused aerosol emissions and changes in cloud cover have reduced surface radiation levels by 10–15% between 1960 and 2015, the researchers found. If China introduced strict pollution controls for sulfur dioxide and black carbon and limited fossil-fuel consumption, it could return to 1960s solar radiation levels, which would increase solar electricity generation by 12–13%. That increase, applied to China’s 2016 solar photovoltaic capacity, translates to an economic benefit worth $1.9 billion in increased solar production. China is already making progress toward reducing its air pollution, so the “findings should be interpreted as a possible cobenefit of air pollution control in China,” the researchers write.