No country has lived with the data centre boom as intensely as Ireland, and the Central Statistics Office's latest release shows how far it has gone. Metered electricity consumption by data centres rose by 10 per cent in 2024, from 6,335 GWh in 2023 to 6,969 GWh. Consumption by every other user, households and businesses together, rose by 3 per cent. Data centres took 22 per cent of all metered electricity in the country, up from 5 per cent in 2015.
To put that share in context, the CSO notes that urban households accounted for 18 per cent of metered consumption in 2024 and rural households for 10 per cent. Data centres alone now use more electricity than all of Ireland's urban homes. They are also the main reason that total metered consumption rose by 30 per cent between 2015 and 2024, an unusual pattern for a European economy where electricity demand has been flat or falling in most countries for much of that period.
A quarterly series tells the story
The release, published on 10 June, is the first to track data centre consumption quarterly from 2015. The series is striking. Consumption rose steadily from 290 GWh in the first quarter of 2015 to 1,829 GWh in the fourth quarter of 2024, an increase of 531 per cent. There is no visible plateau. Each year has added more than the year before in absolute terms for most of the period, and the growth continued in 2024 even as constraints on new connections in the Dublin region tightened.
The CSO's statistician, Dr Grzegorz Głaczyński, also pointed to the broader category of large energy users, which typically includes the larger data centres. They made up the largest share of metered consumption in 2024, at 31 per cent, with demand of 9,897 GWh, a 9 per cent increase on the previous year. The difference between the large energy user category and the data centre category gives a sense of how much of Ireland's heavy industrial and commercial demand is now digital.
Why Ireland is different
Ireland became Europe's data centre hub for familiar reasons: a favourable corporate tax regime, an English-speaking workforce, the European headquarters of many American technology companies, a temperate climate that reduces cooling needs, and good subsea fibre connections. It also has a small electricity system. The all-island system serving Ireland and Northern Ireland is small by European standards, which means that each new hyperscale campus is a large addition relative to the whole.
That is the crux of the problem. In larger markets such as Germany or the United States, data centres are a few per cent of national demand even when they dominate particular regions. In Ireland they are more than a fifth of the national total. The system operator, EirGrid, and the regulator, the Commission for Regulation of Utilities, have had to manage data centres as a matter of national security of supply, not just local network planning.
The constraints are already binding
The policy response has been restrictive. Since 2021 the CRU has required new data centres to bring dispatchable on-site generation or storage to match their demand, and the transmission system operator has treated new connections in the Dublin area with great caution because of constraints on the network there. The effect shows up in the growth rate. A 10 per cent annual increase is still fast, but it is below the rates seen earlier in the series, and it reflects mostly the filling-up of campuses already connected rather than new ones.
The constraints have a cost. Some investment that might have come to Ireland is going elsewhere in Europe, to the Nordics, the Netherlands, Spain and the United Kingdom. Others are locating in Ireland but outside Dublin. At the same time, data centres have become a political issue, with arguments about whether their consumption undermines Ireland's climate targets, crowds out housing and electrification, or raises prices for households.
The climate arithmetic
Ireland's climate targets are set in carbon budgets, and the electricity sector has a ceiling on emissions. Every additional terawatt-hour consumed by data centres must be met by generation, and when the wind is low, that generation is mostly gas. The data centre operators sign long-term power purchase agreements for wind and solar, and some have funded new projects. But the timing does not always match: a data centre draws power around the clock, and on a calm winter evening the marginal unit on the Irish system is a gas plant regardless of what contracts say.
That tension is why the debate in Ireland has shifted from whether data centres should connect to on what terms. Requiring on-site generation that can run in the wholesale market, demanding that new demand be matched by additional renewable projects, and steering connections towards parts of the network with spare capacity are all options under discussion. Each one shifts cost and risk from the system to the developer.
What to watch
The next set of figures will show whether the 2024 growth rate holds. Several campuses connected in recent years are still ramping up, so further increases are likely even with few new connections. The more important question is the policy framework for the next wave. A new large energy user connection policy is expected from the CRU, and its terms will decide whether Ireland remains a destination for the AI facilities now being planned, or whether the country's data centre share settles at around a fifth of demand while new capacity is built elsewhere.
The data also matter for how other countries measure the issue. Ireland is unusual in publishing a dedicated official series on data centre consumption, built from metered data rather than estimates. Most countries rely on industry surveys or modelled figures, which makes cross-country comparisons uncertain. The CSO series gives Irish policymakers a firm baseline and a quarterly read on the trend, something regulators elsewhere still lack.
Ireland is often described as a warning to other countries. It is more accurately a preview. Other small and medium-sized systems that attract hyperscale investment, from Denmark to Malaysia, are likely to face the same choices within the decade.