New pumped storage scheme for Snowdonia?

Snowdonia Pumped Hydro (SPH) has submitted an application to the Planning Inspectorate to build a 99.9 MW pumped hydro electricity storage facility at Glyn Rhonwy near Llanberis in North Wales. The scheme, which already has planning permission from local authority Gwynedd Council at an output of 49.9 MW, would re-purpose two abandoned slate quarries for energy production.

SPH now wishes to double the output of the Glyn Rhonwy facility by increasing the capacity of the underground turbines and associated equipment. In every other respect the revised scheme would be the same as that already granted planning permission by Gwynedd Council. As a ‘Nationally Significant Infrastructure Project’ of 50 MW or more, permission for the larger scheme is evaluated by the Planning Inspectorate rather than the local authority.

The higher output would enable the Glyn Rhonwy facility to play a larger role in smoothing out the intermittency of renewables such as wind by capturing surplus electricity and releasing it when demand is high and output from renewables is low.

Britain’s need for more grid-scale storage such as that planned at Glyn Rhonwy is now firmly on the government’s agenda, says SPH, and the growth of renewable generation has already left the UK’s four existing storage plants – originally built to back-up nuclear power stations – unable to cope. The storage deficit also means that gas power stations and diesel generators must be kept on stand-by for when the wind drops or stops altogether.

The Glyn Rhonwy facility would be expected to have an operational life of around 125 years and support up to 30 full time local jobs.