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Elan Valley hydroelectric image

Elan Valley
Rhayadar, Wales

Between 1893 and 1904, Birmingham City Council built a series of dams in the Elan Valley to supply clean, safe water to Birmingham.

The population of Birmingham had grown rapidly during the Industrial Revolution and clean water was in short supply, so there were epidemics in diseases such as typhoid and cholera.

The project meant that about one hundred people had to leave the valley because homes, farms, a school and a church had to be demolished so the new reservoirs could be built. The reservoirs dramatically changed the local landscape.

King Edward VII and Queen Alexandra officially opened the Elan Valley Dams on 21 July 1904.

Picture of Pen Y Garreg Dam, Elan Valley. Courtesy of Elan Valley Ranger Service and Headstart Web Services.

Dinorwig Power Station
Gwynedd, Wales

Dinorwig Power Station began generating electricity in 1984. It is the largest pumped-storage facility in Europe and has a capacity of 1728MW. The six installed turbines stand in the largest man-made cavern in Europe and can reach maximum power in just 16 seconds. This quick response time makes hydroelectricity an extremely flexible resource.

Using off-peak electricity, the turbines can be reversed to act as pumps to transport water from the lower reservoir back up to the higher one.