Cooling water for Britain's future electricity supply

Abstract

Trends in the locations and technologies of UK electricity generation plant suggest that demand for cooling water abstractions from rivers will decrease in the coming decades, unless there is widespread uptake of carbon dioxide capture and storage (CCS). CCS may prove to be essential if the UK is to achieve its carbon dioxide and greenhouse gas emission targets. ‘Decarbonisation’ strategies that rely on CCS are therefore potentially at risk of not having sufficient cooling water in periods of low river flows. In this paper, regional freshwater demands for cooling water are assessed against regional freshwater availability at low flows in a scenario of medium climate change. In the strategy with high CCS, demands for water greatly exceed current and future availability in the north-west (NW) England, Humber, East (E) Midlands and Thames regions. These risks can be mitigated by increasing the penetration of hybrid cooling systems or shifting generating capacity to estuaries or the coast. The former could reduce national water use by up to 35%, whereas applying the latter in the NW England, Humber and E Midlands regions offers nationwide reductions from 30 to 50%.