Hydroelectricity in the United Kingdom

As of 2018, hydroelectric power stations in the United Kingdom accounted for 1.87 GW of installed electrical generating capacity, being 2.2% of the UK's total generating capacity and 4.2% of UK's renewable energy generating capacity. This includes four conventional hydroelectric power stations and run-of-river schemes for which annual electricity production is approximately 5,000 GWh, being about 1.3% of the UK's total electricity production.[2] There are also pumped-storage hydroelectric power stations providing a further 2.8 GW of installed electrical generating capacity, and contributing up to 4,075 GWh of peak demand electricity annually.[3]

The Dinorwig Power Station lower reservoir, a 1,800 MW pumped-storage hydroelectric scheme, in north Wales, and the largest hydroelectric power station in the UK

Hydroelectricity accounted for 4.2% of electricity generation from renewable sources in the United Kingdom (2018)[1]

The potential for further practical and viable hydroelectricity power stations in the UK is estimated to be in the region of 146 to 248 MW for England and Wales,[4] and up to 2,593 MW for Scotland.[5] However, by the nature of the remote and rugged geographic locations of some of these potential sites, in national parks or other areas of outstanding natural beauty, it is likely that environmental concerns would mean that many of them would be deemed unsuitable, or could not be developed to their full theoretical potential.

Interest in hydropower in the UK rose in the early 2010s due to UK and EU targets for reductions in carbon emissions and the promotion of renewable energy power generation through commercial incentives such as the Renewable Obligation Certificate scheme (ROCs) and feed-in tariffs (FITs). Before such schemes, studies to assess the available hydro resources in the UK had discounted many sites for reasons of poor economic or technological viability, but studies in 2008 and 2010 by the British Hydro Association (BHA) identified a larger number of viable sites, due to improvements in the available technology and the economics of ROCs and FITSs.[4][5] However, during the same period there have been significant reductions in costs of other renewable energy sources such as Offshore Wind and Photovoltaics,[6] this has resulted in reduced competitiveness of large scale Hydroelectric schemes in the UK. There are no large scale Hydroelectric scheme planned in the UK as of 2020. However, it is predicted that pumped storage will play an increasingly important role in the UK electricity grid in future years as more intermittent sources of electricity generation come on line.[7]

Schemes up to 50 kW are eligible for FITs, and schemes over 5 MW are eligible for ROCs. Schemes between 50 kW and 5 MW can choose between either. The UK Government's National Renewable Energy Action Plan of July 2010 envisaged between 40 and 50 MW of new hydropower schemes being installed annually up to 2020. The most recent feedback for new hydro schemes is for 2009, and only about 15 MW of new hydropower was installed during that year.[2]