Rheidol hydropower plant is located near the town of Aberystwyth in the Ceredigion area in Mid-Wales, United Kingdom.

Ownership: 100 %
Annual production: 89 GWh
Power: 49 MW

The power plant is the largest of its kind in England and Wales. The plant has generated renewable energy by using rainwater that falls on the surrounding mountains since 1962.

The plant is made up of an interconnected group of reservoirs, dams, pipelines, aqueducts and power stations and covers a total area of 162 square kilometres.

The upper reaches of the scheme are over 750 meters above sea level up in the remote Plynlimon mountain range. A series of aqueducts collects the water and channels it into the Nant-Y-Moch reserviour. Water flows from this reservoir to a power station at Dinas where it drives a 13,000 KW generator. From the power station, the water flows into Dinas reservior.

Dinas reservoir supplies water to the largest power station at Cwm Rheidol where there are two 20,500 KW generators. At Cwm Rheidol a further reservoir has been created to avoid large variations in the flow of water. This reservoir collects water that flows through the power station and releases it slowly through a 1,000 KW generator.