Gas Networks Ireland’s latest Gas Demand Statement shows that residential gas demand almost tripled in September 2025, as cooler, wetter weather1 prompted households to turn on their heating.
According to Met Éireann, September was the wettest month of 2025 so far, and was relatively cool overall, with an average temperature of 13°C1. The change in conditions contributed to a significant rise in domestic gas use and one of the largest month-on-month increases in residential demand this year of +168 per cent.
While household consumption rose sharply, overall gas demand fell by 4 per cent compared to August 2025 and was 9 per cent lower than in September 2024, primarily due to a decline in gas use for electricity generation. Gas demand in the electricity generation sector fell by 14 per cent month-on–month and by 12 per cent year-on-year.
However, several sectors recorded strong month-on-month increases including education2 (+77 per cent) as schools and colleges reopened, to offices3 (+47 per cent), as well as leisure and sports facilities (+40 per cent).
Electricity generation
Gas generated 37 per cent of Ireland’s electricity in September, peaking at 75 per cent and never falling below 13 per cent4. While this was down from both August (45 per cent) and September 2024 (44 per cent), gas continued to play a vital role in supporting the electricity system during periods of low renewable generation.
Wind accounted for 34 per cent of electricity generation, up from 27 per cent in August and 30 per cent in September last year, but the energy output from wind fluctuated widely — peaking at 76 percent and falling to one per cent at times4. Solar energy contributed 4 per cent, peaking at 21 per cent at times4.
Despite stronger renewable contributions overall, both wind and solar output fell away almost completely at times, underlining the ongoing need for gas to provide flexibility and ensure a secure energy supply.
Commenting on the latest gas demand data, Edwina Nyhan, Gas Networks Ireland’s Director of Strategy and Regulation, said:
“September’s figures clearly show how weather patterns drive energy use across Ireland. While overall gas demand was down, cooler and wetter conditions led to a sharp rise in residential consumption. Gas also continued to underpin Ireland’s electricity system, providing stability at any time when renewable output dipped.
Gas Networks Ireland recently announced an agreement with Evergreen Agricultural Enterprises to connect a new €50 million biomethane plant in Kildare directly to the national gas network. Once operational, the facility will convert by-products from Ireland’s distilling industry into renewable biomethane — enough to heat around 8,000 homes every year and cut Ireland’s emissions by approximately 20,000 tonnes annually.
Speaking about the Evergreen announcement, Ms Nyhan said:
“We’re making real progress in decarbonising Ireland’s gas network. Evergreen is a fantastic example of Irish industry turning waste into clean, home-grown energy and demonstrates how existing gas infrastructure can deliver renewable energy solutions. Evergreen is the sixth biomethane project to enter a gas network connection agreement in just two years, and together these plants will account for around ten per cent of Ireland’s national biomethane target. Momentum is really building, and we’re starting to see real ‘green shoots’ in the biomethane market.”
1 Climate Statement for September 2025 - Met Éireann - The Irish Meteorological Service
2 ‘Education’ refers to large educational campuses
3 ‘Offices’ refers to large office campuses
4 All peak and low measurements recorded over a 15-minute resolution
