Scottish Power is planning to double the size of its hydro-electric power plant by building a new dam.
The Cruachan in Scotland which creates and stores energy, will be doubled in size according to Scottish Power, who are planning to build a new dam in front of the existing dam, saying that the UK will need much more energy storage capacity as renewables increase on the National Grid.
It says it can add 400 megawatts (MW) of on-demand electricity by building the new dam. Scottish Power will spend £300-£400M on the new project, but says it is prohibitive unless it can get a guaranteed floor price for its use from the government.
In return, Scottish Power says it will accept a cap on profits.
The Cruachan plant near Oban in Scotland pumps water 400m uphill at night when energy prices from wind farms are cheap. In the daytime, it then lets the water flow downhill to generate electricity when demand peaks and power prices are expensive.
Scottish Power’s Neil Clitheroe said: “Pumped hydro is ideal because it’s relatively cheap, it’s virtually instant, and it provides power at scale. We will need much more of this sort of thing when we get more wind power on the system.”
With renewables producing much more power, Ministers have recognised that energy storage in the UK needs to be radically improved.
Scottish Power calculates that its pumped hydro system stores the same amount of energy as seven million car batteries.
The Chancellor George Osborne’s National Infrastructure Commission will soon offer its recommendations on the issue.
A Department of Energy & Climate Change (DECC) spokesperson said: “We recognise the potential for storage technologies, including pumped hydro storage, to help us use energy flexibly. Our priority is providing clean, secure energy at the lowest possible price for families and businesses.”
Cruachan is the second biggest of four pumped hydro systems in the UK, generating a full load for 14.5 hours, capable of reaching full power in less than a minute.