Once the heat generated by nuclear fission has finished spinning the turbines in nuclear power plants, it must somehow be dissipated into the wider environment. Almost invariably, this is done using large amounts of water drawn from nearby rivers and lakes. Now, for plants located in drought-struck regions such as the southeast United States, possible water scarcity threatens to shut down plants, forcing the costly purchase of energy from other jurisdictions.
The Associated Press estimates that 24 of America’s 104 nuclear reactors are located in areas currently experiencing severe drought. On reactor outside Raleigh, North Carolina will need to be shut down if water levels in the lake fall by another 3 1/2 feet. In total, nuclear power provides about 10% of the American supply of electricity. All but two American nuclear plants are cooled using water from lakes and rivers. Some plants evaporate large amounts of water from cooling towers, while others are designed to return the warmed water to the body that originally provided it. Immersing collection pipes at lower levels risks being costly, as well as increasing problems from sediment intake into the cooling system.
All this demonstrates the degree to which many forms of low-carbon energy generation are themselves vulnerable to climate change. Concern about water being a limiting factor in energy production is already acute in Australia. Dams face risks from both drought and the loss of snowpack in mountain ranges (leading to too much water at some times of year and not enough at others). Even wind turbines may be vulnerable to changes in dominant patterns of air circulation. Designing future infrastructure with possible climate changes in mind is essential, if we are not to find ourselves with a lot of expensive hardware rendered useless by changed conditions.