Drought and climate change impacts on cooling water shortages and electricity prices in Great Britain

The risks of cooling water shortages to thermo-electric power plants are increasingly studied as an important climate risk to the energy sector. Whilst electricity transmission networks reduce the risks during disruptions, more costly plants must provide alternative supplies. Here, we investigate the electricity price impacts of cooling water shortages on Britain's power supplies using a probabilistic spatial risk model of regional climate, hydrological droughts and cooling water shortages, coupled with an economic model of electricity supply, demand and prices. We find that on extreme days (p99), almost 50% (7GW(e)) of freshwater thermal capacity is unavailable. Annualized cumulative costs on electricity prices range from 29-66m.yr(-1) GBP2018, whilst in 20% of cases from pound 66-95m.yr(-1). With climate change, the median annualized impact exceeds pound 100m.yr(-1). The single year impacts of a 1-in-25 year event exceed > pound 200m, indicating the additional investments justifiable to mitigate the 1(st)-order economic risks of cooling water shortage during droughts. p id=Par The impacts of power plant water shortage during drought on electricity prices are understudied. Here the authors show that on extreme days, almost 50% (7 GWe) of the freshwater thermal capacity is unavailable in the Great Britain and annualized cumulative costs on electricity prices are in the range of pound 29-95m per year.