EirGrid may call on emergency power this winter

National grid operator EirGrid may have to call on emergency power plants to shore up electricity supplies as demand heads for a likely record this winter, a new report is set to show.
The State company’s latest Winter Outlook, a snapshot of likely electricity supply and demand for the coming months, shows the risk of any home or business losing power has fallen sharply on previous years.
EirGrid has temporary emergency gas- and diesel-fuelled power plants to call on “as a last resort” this winter if demand outruns supplies available from the all-Ireland electricity market. The four plants, built over the last year, can generate a total of 505 megawatts (MW) between them, slightly more than what the average Irish natural gas-fired power station can produce.
Two of them, on Dublin’s North Wall and on Energia’s site in Huntstown in the north of the county, run on gas. The other two, in Shannonbridge, Co Offaly, and Tarbert Co Clare, run on distillate, a form of diesel, according to EirGrid.
They can be switched on rapidly to meet surges in demand, which are most likely around evening times in mid-winter.
The company stresses that “ideally” it should not have to call on the emergency generators, and says it will only use them as a final backstop when electricity supplies come under pressure.
Demand could peak at a new record of 5,834MW this winter, topping the 5,577MW hit during a cold spell last January, EirGrid predicts in its Winter Outlook 2024, due to be published on Tuesday. Extra demand will come from an increased number of businesses that use large quantities of electricity, including data centres, new homes and general economic growth.
The grid operator also has three new gas-fired power plants, capable of generating 190MW, built by the ESB around Dublin to call on this winter. These are not emergency facilities and will sell their electricity to the market.
Alongside that batteries capable of providing up to 270MW over two or three hours will be available to supply power. Batteries store electricity from renewables and other sources during periods when demand is low and can then be called on supply that power when it is needed.
The Republic has increased the amount of electricity imported from Britain in recent years, a trend the grid company expects to continue.
EirGrid says electricity supplies will be more secure this winter than in previous years. The State company estimates through the winter, from the end of this month to late March, that demand will outstrip available power supplies for three hours and 36 minutes in total. That compares to 21 hours last winter and 53 hours in 2022/23. EirGrid points out that it did not have to cut electricity supplies to any customer in either year.
The extra supplies mean that the risk of the company issuing “system alerts” warning about the immediate security of supplies is also lower than in previous years. In the past EirGrid has issued amber alerts cautioning about adequacy of reserve electricity supplies. There were no such alerts last winter.
It acknowledges that the risk of it issuing those warnings will be most likely at times when wind and imports from Britain are low.
“The probability of the system entering the emergency state – red – due to insufficient generation available to meet demand is deemed to be low this winter,” the company says.
Diarmaid Gillespie, Eirgrid’s director of system operations, said it was “positive to see that the situation has improved considerably this winter compared to previous years”.