Solar power production has slowed due to the depletion of coal

Regional differences

The researchers note that aerosols can also contribute to the formation of clouds, causing further damage. But the amount of the contribution is very difficult to estimate, so the researchers focused on aerosols in the main analysis. Some of these aerosols occur naturally, especially from dust blown by the wind in desert areas. However, despite the fact that deserts are known as solar paradises, the whole world has not yet built many solar installations in the desert, so this is not much to expect.

Coal seems to be contributing a lot. It is estimated that sulfur dioxide aerosols, which are produced by burning coal, make up about half of the aerosols currently being analyzed. Carbon dioxide, which also comes from fossil fuels, also makes up 18 percent.

The effects of aerosols, however, are not evenly distributed. In China, the researchers estimate that aerosols reduce solar production by 7.7 percent overall and reduce it anywhere from one-third to one-half of its annual growth rate. The researchers note that “the distribution of photovoltaic losses in China reflects its coal-burning power,” and an analysis of emissions from China shows that 30 percent of losses due to aerosols can be attributed to coal burning.

In contrast, most solar production in the US occurs in the South and West, while coal plants are common in the East and Northeast. As a result, annual losses in the US were less than half of those seen in China (3 percent).

The good news is that things are improving in China. In order to deal with the serious problems of environmental degradation, the country built a new generation of high-efficiency coal plants and abandoned other highly destructive projects. And data shows that this is also benefiting from solar energy, with the effect of aerosols decreasing over the last few years.

Despite the change, it is surprising that coal seems to be the only source of electricity that is reducing the productivity of what is becoming its primary competitor. They should also provide an incentive to remove coal more quickly, as some of the damage to coal is reduced due to increased coal consumption.

Nature Sustainability, 2026. DOI: 10.1038/s41893-026-01836-5