Rheidol Hydropower Plant

Location

Rheidol Hydropower Scheme is situated in the beautiful Cwm Rheidol valley, eight miles from Aberystwyth, in Mid-Wales. Since the early 1960s, it has generated renewable energy using rainwater that falls on the surrounding mountains and is the largest hydropower scheme of its kind in England and Wales.

The environment was taken into consideration when designing this award-winning scheme in the 1950s. The Felin Newydd Falls in Cwm Rheidol were designed to blend in with the surrounding countryside, and many of the scheme’s buildings are clad with local stone.

About the plant

The hydropower scheme  is made up of an interconnecting group of reservoirs, dams, pipelines, aqueducts and power stations, and covers a total area of 162 square kilometres. The annual energy production is about 93 GWh, enough to power around 35,000 homes with clean, green electricity. 

From Rheidol, the Statkraft UK and Ireland Control Room operates and maintains the hydro-electric scheme, as well as a number of onshore wind farms, solar farms, and Greener Grid Parks.

How does it work?

A series of aqueducts collects the water and channels it into the Nant-Y-Moch reservoir. From there, water flows to a power station at Dinas featuring a 13 MW generator.

The additional reservoir at Dinas then supplies water to the largest power station at Cwm Rheidol with two 20.5 MW generators. At Cwm Rheidol, a further reservoir has been created to avoid large variations in the flow of water down river towards Aberystwyth. This reservoir collects the water that flows through the power station and releases it slowly through a 1 MW generator at Cwm Rheidol Dam.

Sustainability focus

The land at Rheidol is unique, with some classified as a Site of Special Scientific Interest including vast heather beds, therefore a focus on the local environment is central to our work. We co-operate closely with Natural Resources Wales (NRW) and the Environment Agency regarding our operations and encourage biodiversity at all opportunities including tree felling and landscaping where logs are left in place for wildlife. We also provide fenced off areas for ant colonies in the forestry behind the main station.

The River Rheidol is an integral part of the Rheidol hydropower scheme and also a breeding area for salmon and trout. The fish originally had to pass Trotter’s Falls to reach their spawning grounds but when the Falls were replaced by a new dam, weir and bridge at Felin Newydd we constructed a special 'fish lift' to allow the fish to reach their old spawning grounds. Upstream of the power station a 'fish ladder' was cut into the rock to bypass the Rheidol Falls and thus opened up new spawning grounds to the fish. The fish ladder rises six metres and has 14 pools.