A grid scale hydropower energy storage facility has been approved planning permission in the UK.
Construction of Snowdonia Pumped Hydro’s (SPH) project to turn two abandoned slate quarries in North Wales into water reservoirs could now begin as early as 2018.
The site in Glyn Rhonwy is expected to store around 700MWh of electricity, enough to supply 200,000 homes with electricity for seven hours a day over a projected operational lifetime of more than 125 years.
The facility will use surplus electricity from wind and solar sources to pump water from the lower to the upper reservoir.
When the power is needed, the water will flow back down the tunnel, spinning a turbine and regenerating 99.9MW of stored electricity.
SPH is currently seeking private equity funds to build the Glyn Rhonwy scheme without public money.
The firm estimates 50GWh of pumped hydro storage is available in the UK if unconventional sites like old quarries, coastal locations and existing drinking water reservoirs are used.
SPH Managing Director Dave Holmes said: “Glyn Rhonwy can be expected to deliver around 32 million MWh over its lifetime. An equivalent 700MWh Lithium-ion installation would deliver just 2.1 million MWh before needing its batteries replacing.
“This means electricity delivered by pumped hydro is 20 times cheaper per MWh than Lithium-ion batteries over its lifetime and carries less environmental baggage.”
Another pumped storage hydro plant in Scotland has been given the green light.