An Irish-owned energy company has unveiled plans to develop a major long-duration energy storage plant not far from Tullow in Co Carlow.
The facility will use surplus renewable electricity to separate hydrogen from wastewater in a process called hydrolysis.
That surplus electricity from wind and solar farms is currently being lost due to a lack of demand at certain times and because of inadequate grid capacity to absorb power.
The hydrogen generated will be compressed and stored deep underground below the site in lined rock caverns constructed in granite.
Then, when electricity is needed, such as during periods of low wind or solar output, the hydrogen will be released from storage and used as a fuel in a gas turbine power plant above the site to generate reliable, dispatchable, clean electricity.
This will ensure that renewable electricity is returned to the grid when it is needed most.
The project is designed to produce a peak power output of 600 megawatts for 70 hours.
That is enough to power 10% of Ireland’s peak electricity needs, enough to meet the electricity demands of the counties Carlow, Kilkenny, Laois and Wexford combined.
The project, which will cost approximately €2 billion to develop, is known as Rathrush Green Energy Park and is being developed by Irish firm Net Zero Energy (NZE).
The proposed site for the development is located outside Rathoe in Co Carlow.
It is estimated that it will save 180,000 tonnes of CO₂ emissions per annum, which equates to taking approximately 40,000 cars off the road.
At peak, there will be up to 1,500 workers on-site during the construction phase, with some 70 long-term, highly skilled jobs created once complete.
Rathrush Green Energy Park will store 30 times more green energy than Turlough Hill and have seven times the generation capacity of Ardnacrusha.
Following a community consultation programme, the developer hopes to be in a position to lodge a planning application by the end of this year.
NZE chief executive Peter Harte said: “The project presents an important as well as timely solution to the current pressing and complex energy dilemma facing the country, both in terms of security of supply and decarbonising our grid.
“Moreover, by harnessing an energy source which was heretofore being wasted, we can insulate consumers from future fossil fuel crises and price shocks such as we saw in the aftermath of the Russian invasion of Ukraine in 2022 and more recently in the Middle East.
“By delivering a national solution helping Ireland on its journey to energy independence, it simultaneously provides reassurance and confidence for high-end electricity users seeking to locate here in Ireland,” he concluded.
NZE chairman Tim Cowhig stated: “By making available 600MW of renewable energy at the flick of a switch, this project can satisfy as much as 10% of Ireland’s peak energy requirement. Rathrush Green Energy Park provides significant, secure, sustainable long-duration energy storage for the Irish grid.
“Ireland has never been in such a precarious position in terms of our energy security. We spend €10 billion annually importing fossil fuels.
“This project is particularly timely with widespread debate and focus on Ireland’s climate change targets and the enormous subsequent fines which would result if we fail to meet them,” concluded Mr Cowhig.
