Water shortages could disrupt Britain’s electricity supply

The Guardian reports on a team of academics from Oxford and Newcastle who say nuclear and gas-fired power stations could be forced to shut down during future droughts.

The electricity sector uses large quantities of water for cooling processes in thermoelectric power stations, accounting for around half of all water abstractions in England and Wales. As water resources come under increasing pressures from growing populations and climate change, shortages could have serious impacts on the country’s electricity production, warns a new study co-authored by Professor Jim Hall, Director of the Environmental Change Institute, Oxford University.

“The high dependency on water in electricity generation means there is a real possibility that in just a few decades some power stations may be forced to decrease production or shut down if there are water shortages”, said Ed Byers in the Guardian article, a researcher at Newcastle University and lead author of the study.

The research, published in the journal Global Environmental Change, assesses the water demand of the government’s proposed energy ‘pathways’ to 2050. While some pathways present opportunities to both reduce water dependency and carbon emissions, others increase the dependence on water resources. For example, using fossil fuels with high levels of carbon capture and storage (CCS) could increase freshwater consumption by up to 70%.

The research shows that up to the 2030s, water use performance improves for all pathways, in line with rapid decarbonisation. This is achieved as renewable energy production expands while older coal, gas and nuclear plants are decommissioned and new and more affordable nuclear and carbon capture-equipped generation begins to take shape.

In the 2030s the water security of the UK could be in the balance as the water intensity of the different pathways diverges, warn the researchers. Coal and gas plants would be forced to shut down if they do not adopt CCS, yet if CCS and nuclear power are deployed on wider scales, water intensity will rapidly increase. Developers could be forced to choose between using limited freshwater supplies or increasing abstraction from tidal and sea water, both of which could be problematic for the environment.

The energy pathway with the highest level of renewables uses the least freshwater. Hybrid or air cooling comes at a slightly high cost and more emissions, but minimises water consumption and therefore could reduce dependency on scarce resources.

Read the Guardian article

Reference

Byers, E.A., Hall, J.W. and Amezaga, J.M. (2014) Electricity generation and cooling water use: UK pathways to 2050. Global Environmental Change. DOI: http://dx.doi.org/10.1016/j.gloenvcha.2014.01.005