Coal Pollution Reduces Global Solar Power Output, Study Finds

A joint study by researchers at the University of Oxford and University College London examined more than 140,000 solar photovoltaic installations worldwide using satellite imagery, atmospheric data and machine‑learning analysis. The researchers found that aerosols from coal‑fired power plants cut global solar electricity generation by 5.8% in 2023, representing a loss of about 111 terawatt‑hours – roughly the annual output of 18 medium‑sized coal plants.

The loss is most pronounced in China, which generated over 41% of the world’s solar electricity in 2023 but saw solar output reduced by 7.7%, with around one‑third of that loss directly linked to nearby coal‑plant emissions. Between 2017 and 2023, new solar installations added an average of 246.6 TWh per year, while pollution‑related losses amounted to 74 TWh annually. The authors warn that renewable‑energy forecasts may be systematically overstated if such pollution impacts are ignored and call for stricter air‑pollution controls and faster reductions in coal use. Recent improvements in China’s emissions standards and ultra‑low‑emission coal technologies suggest the trend could be mitigated.