SSE’s Billion Pound Pumped Hydro Plant

By Paul Homewood



Slated as the first large-scale pumped hydro storage scheme to be built in the UK for more than 30 years, Utility Week Innovate digs into plans to deliver up to 1.5GW and 30GWh of storage by 2030 at Coire Glas.

It’s forecast that SSE Renewables’ Coire Glas pumped storage plant – located in Scotland’s Great Glen between Fort William and Inverness – will create enough storage capacity to power three million homes for up to 24 hours when operational. More than doubling Britain’s existing capacity.

After a revised application to increase proposed capacity from 600MW to 1,500MW was approved by the Scottish Government in October 2020, ground was broken in November 2021. The project is expected to take between five and six years to complete, will cost more than £1 billion and boast an operational life of more than half a century.

WOW!! Doubling our electricity storage! It must be impressive.

Except that our electricity storage is so tiny in the first place, that doubling will make little difference.

The claim that it can power 3 million homes is the usual deceptive spin we get from the renewable lobby.

But how long would 30 GWh really last us?

In winter, the UK consumes about 1 TWh a day; that’s 1000 GWh, or 41 GWh every hour. Coire Glas will be able to supply this amount for 43 minutes.

The article claims that this sort of long term storage is vital if high levels of wind power are to be supported:

Large amounts of long-duration energy storage will be required to support accelerated renewable energy plans set out in April’s energy security strategy, in which the government increased its offshore wind target to 50GW by 2030 and committed to onshore wind and solar roll outs that could see 95% of power coming from low carbon sources by 2030.

What’s more, a government document published in August discussing the deployment of large-scale and long-duration electricity storage concluded that it has an important role to play in achieving net zero, integrating and maximising the use of renewables, contributing to security of supply, and shaking up Britain’s technology mix.

The reality is rather different. Less than an  hour’s worth of storage is of little use, other than for balancing ups and downs in demand during the day, or hour to hour volatility in renewable generation. We would need hundreds of Coire Glas style storage plants to cover the periods of days and weeks on end, when the wind stops blowing.

And at a billion pounds a time, who is going to pay the bill?

Interestingly enough, the Utility Week article notes:




This goes to the heart of the economics which make projects like this so unattractive. There are no sizeable or reliable revenue streams, because for much of the time they will be standing idle.

SSE of course see an opportunity to cash in on the highly profitable short term balancing market, probably topped up by Capacity Market revenue. All of this is, of course, to address problems arising from intermittent renewable energy, and all of it has to be paid for by long suffering energy consumers.

But this sort of niche market will only work for a small number of players. To get large numbers of grid scale pumped storage units constructed will need hundreds of billions in taxpayer subsidies.


August 27, 2022 at 03:55AM

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