Where does Ireland get its electricity from?
In 2025, gas met 40.2% of Irish electricity demand, wind 32.7%, net imports 16.4% and solar 3.1% (Ember, share of demand including imports). Measured against electricity made in Ireland only, gas was 48%.
In 2020 Ireland was a small net exporter over the year: net imports were -0.5% of demand. By 2025 they were 16.4%, and 18% in the first 8 months of 2026.
How much electricity does Ireland import?
Net imports were 5.69 TWh in 2025. Over the 12 months to 9 October 2026, the EirGrid dashboard shows an average net import of 558 MW across all hours (some hours export, some import). The power comes through two cables to Great Britain (East-West and Greenlink) and the tie-line to Northern Ireland, which links to Scotland through Moyle.
| Link | Route | MW | In service |
|---|---|---|---|
| Moyle | Northern Ireland - Scotland | 500 | 2002 |
| EWIC (East-West) | Ireland - Wales | 500 | 2012 |
| Greenlink | Ireland (Wexford) - Wales (Pembroke) | 504 | 2025-01-29 |
| Celtic | Ireland (Cork) - France (Brittany) | 700 | 2028-04 (assumed) |
| North-South (second 400 kV) | Ireland - Northern Ireland | 900 | 2031-2032 |
| MaresConnect | Ireland - Wales | 750 | 2029 (promoter target; not in EirGrid studies) |
Interconnector list from EirGrid and CRU documents in our generation pipeline. Dates after today are planned.
Did data centres use up Ireland's new wind power?
For 2017–2023 the comparison holds in accounting terms: extra wind (about 4.3 TWh) and extra data-centre demand (about 4.6 TWh) were similar in size. That is the period behind the December 2024 UCC study for Friends of the Earth, and the Climate Change Advisory Council's 2026 review. Since 2020, though, the picture has changed. 2020 was a very windy year, so it flatters the comparison; measured from 2022 the result is the same (table below).
Since 2020 wind's share of Irish generation has ranged between 31.3% and 37.7% with no upward trend. The growth had to come from somewhere else, and it came from the interconnectors.
| Period | Demand change, TWh | Data centres, TWh | Net imports, TWh | Wind, TWh | Gas, TWh | Solar, TWh |
|---|---|---|---|---|---|---|
| 2015–2025 | +7.4 | +6.42 | +5.01 | +4.78 | +2.41 | +1.06 |
| 2020–2025 | +5.43 | +4.63 | +6.19 | +0.24 | −1.07 | +1.06 |
| 2022–2025 | +3.13 | +2.39 | +5.55 | +0.43 | −1.43 | +1.06 |
Ember: demand = domestic generation + net imports, so the source changes add up to the demand change (rounding aside). Coal, oil, hydro and bioenergy are left out of the table.
What happens overnight?
Data centres run around the clock, so they lift the overnight minimum most. In the quietest tenth of quarter-hours, demand rose from 2,319 MW in 2019 to 3,250 MW in the last 12 months. Data centres' average draw rose from 284 to 875 MW over the same span.
At that overnight floor Ireland used to export 176 MW. It now imports 592 MW. Wind at the floor rose 314 MW and gas changed by an estimated -67 MW.
Why it matters
Emissions accounting. Ireland's inventory counts imported electricity as zero. Grid-attributed data-centre emissions fell from 1.7 Mt in 2022 to 1.46 Mt in 2025 while use rose from 5.3 to 7.7 TWh.
Our reading. Part of that fall is a cleaner Irish grid, and part is emissions moving to Great Britain's books. Data centres look cleaner on paper than the system that serves them.
Security of supply. EirGrid's adequacy study puts Ireland 1,010 MW short of its reliability standard in 2026 in the base case, before emergency measures. That is about the same as data centres' average draw. Imports help only when Great Britain has power to spare at the same moment.
Policy. The CRU's December 2025 rules require new data centres to match 80% of their demand with new Irish renewables, a test the growth since 2020 would not have met.
Our reading. This is an accounting match, not a trace of electrons. No one can say which megawatt-hour went where. What the data shows is that the growth in demand and the growth in imports were the same size.