New electricity demand records set during cold snap

Ireland recorded two new all-time electricity demand peaks as cold weather set in this week, according to grid operator EirGrid.

Levels of demand on the power system reached new highs during the previous cold spell in November, and this was again surpassed this week with demand peaks of 5,716 MW (Megawatts) recorded at 5.53pm on Tuesday 7 January, and 6,024 MW recorded at 5.47pm on Wednesday 8 January.

Wednesday’s peak and new record is of particular significance as this marks the first time that peak electricity demand has passed the 6,000 MW mark. Around 60% of electricity generation was coming from gas at this time, with 17% from renewables and further contribution from batteries, and imports accounting for 6.6%.

For context, demand first passed the 5,000 MW mark during the extreme cold snap of December 2010, a record which stood for another 10 years before being surpassed in December 2020 and on a number of subsequent occasions including this week.

Wednesday also saw a new full-day energy demand record, where energy use totalled 119.34 Gigawatt hours (GWh). 

In addition, the beginning of the cold snap last weekend saw new demand peaks set for a Saturday (5,287 MW, Saturday 4 January) and a Sunday (5,134 MW, Sunday 5 January).

EirGrid is responsible for operating, developing and enhancing the electricity grid and market in Ireland. It carries out the complex task of matching electricity supply to customer demand in real time from the National Control Centre in Dublin.

Electricity demand in the winter is heavily influenced by weather conditions. EirGrid’s analysis of Ireland’s peak demand over winter indicates that a 1°C decrease in outside temperature results in a 40 MW increase in peak demand (50 MW when wind-chill is taken into account).

Despite the high demand, no System Alerts indicating tight margins between electricity generation and demand were issued over the course of the week.

Diarmaid Gillespie, Director of System Operations at EirGrid, said: “The extended cold spell this week saw electricity demand reach record highs. Our Control Centre staff were able to rely on a mix of generation options over the course of the week to ensure this demand was met, with a sufficient buffer maintained between generation and demand.

“Since seeing the demand peak from the winter of 2010 passed in late 2020 we’ve seen a series of new demand records being set over the last four years, with peak demand rising by almost 900 MW in this space of time.”

In October, EirGrid’s annual Winter Outlook indicated a reduced risk of electricity generation not being able to meet demand compared with previous winter periods.

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