Nuclear Reactors & Climate Change
Posted: 13th September 2025
Declining water levels in French rivers have revealed a key weakness in relying on nuclear power to supply clean energy in a climate emergency— nuclear reactors need to cut output when climate change lowers water levels and raises water temperatures, even as energy demand rises. “While a lot of the nuclear public relations relates to nuclear as a sort of saviour of climate change, unfortunately, the reverse is true,” Paul Dorfman, chair of the Nuclear Consulting Group and a senior academic at the University of Sussex, told Ankara, Türkiye-based Anadolu Ajansi. “Nuclear will be a significant and early climate casualty.” The interplay of climate change, water, and nuclear power is fairly straightforward. Climate change increases the occurrence of both heat waves and droughts, which lower water levels and raise demand for energy to power cooling appliances. Nuclear power plants rely on access to freshwater to cool reactors. If there is not enough freshwater for cooling, or that water is too warm, the nuclear plant needs to scale back, even as consumers crank up their air conditioners.