GoKawiilCoal is by far the most polluting fuel that we use. It produces the most carbon emissions per unit of energy, and impurities in the coal produce a lot of sulfur dioxide aerosols, as well as nitrous and nitrogen oxides. Then there’s the coal ash that’s left behind, which typically contains a lot of toxic metals. The health benefits of displacing coal power are typically estimated to be well above the costs of the new generating equipment.
But a new study suggests that the problems with coal-derived pollution go beyond health; it interferes with other power sources. Researchers have found that aerosols, both natural and human-derived, significantly reduce the power we could be getting from solar panels, to the tune of hundreds of terawatts a year. And a lot of those aerosols come from burning coal.
A big impact
The new work, done by a team in the UK, is based on a new global inventory of solar facilities. This started with known inventories of solar facilities, and was supplemented with AI-analyzed satellite imagery and crowdsourced records of locations. Satellite images were then used to determine the size of these facilities, and location-tagged weather data could then be used to estimate their power production.
That could then be used to estimate what the facilities would be producing if clouds and/or aerosols weren’t scattering the sunlight that would otherwise reach the panels. This produced some significant numbers. In 2023, for example, over a quarter of the potential solar power production was lost, with over 20 percent due to clouds and another 6 percent from aerosols. That works out to be a bit over 500 terawatt-hours, or the full annual output of 84 coal plants (each with a 1 GW generating capacity).
Aerosols alone are a major contributor to these losses. The researchers note that, for the five years leading up to 2023, we installed enough solar capacity to produce an average of 250 TW-hr of additional power per year, but were losing 75 TW-hr of that to aerosols. (Obviously, solar production kept going up because the existing capacity rose each year.)