EirGrid forecasts significantly lower potential for system alerts this winter

EirGrid, which is responsible for operating, developing and enhancing the electricity grid and market, has indicated that there is a significantly lower risk for system alerts in the coming months, compared to what was anticipated last year, as the Winter Outlook for 2024/25 is published.

The annual Winter Outlook helps to inform the electricity industry and supports preparation for the coming months. This year, it covers the period from 4 November 2024 to 6 April 2025. 

EirGrid studies the expected generation capacity and the forecast electricity demand to determine if there is adequate generation capacity margin. 

The Winter Outlook then identifies periods where the margin between generation capacity and forecast peak demand is low, and the security of supply of the electricity system may be at risk. 

It is a point in time assessment, based on the best information available. 

The Winter Outlook identifies the Loss of Load Expectation (LOLE) which is a mathematical formula, based on studies, of the number of hours in a period (typically per year) during which the available generation will be inadequate to meet demand. 

The higher this number is, the greater the risk that there will be insufficient generation available. 

According to this year’s Winter Outlook, the LOLE in Ireland for the five months of the winter period is 3.6 hours, which is just outside the 3 hour annual LOLE Standard which is set for Ireland. 

The LOLE for this winter is down considerably from 21 hours last winter, and from 51 hours the winter before. 

The situation has improved for a number of reasons, including the continued implementation of the Security of Supply Programme which is led by the Commission for Regulation of Utilities (CRU). 

Through this programme, 505 MW of Temporary Emergency Generation (TEG) is now available as an additional generation option to engineers in EirGrid’s Control Centre if required. 

In addition, 190 MW of new gas fired generators and 270 MW of new batteries will be available this winter delivered through auctions in the Capacity Market. 

There remains a risk this winter that the system will enter System Alert (Amber) State at times, most likely at periods of low wind and low interconnector imports, however this risk is deemed much lower than the previous winter. 

The probability of the system entering the Emergency State (Red), due to insufficient generation being available to meet the demand is deemed to be low this winter. 

Grid Alerts do not necessarily mean that electricity consumers will be without supply for any period. 

Emergency protocols are in place with large energy users that would mitigate the impact on homes and businesses, where sufficient notice of an event can be provided (minimum of 1 hour). Temporary Emergency Generation is also available.

Commenting on EirGrid’s Winter Outlook, Diarmaid Gillespie, Director of System Operations at EirGrid, said: “Ireland’s energy demands are monitored by EirGrid’s National Control Centre which carefully balances supply and demand at all times. 

“Ensuring there is sufficient generation to meet electricity demand can be a challenging task, particularly during the colder winter months.  It’s positive to see that the situation has improved considerably this winter compared to previous years.

“The securing of new generators and battery storage units through the Capacity Market, and Temporary Emergency Generation has been key to delivering this improved position. 

“While the situation was more challenging last year, there was only one system alert due to reduced generation capacity margins and no system emergency during Winter 2023/24. This was due to daily engagement and reciprocal support arrangements with transmission system operators in Great Britain and Continental Europe. 

“We will continue to meet the needs of electricity demand growth in Ireland as we manage the secure transition to a renewable led power system in a complex and evolving supply-demand dynamic.”