Data centres used 22 percent of Ireland’s metered electricity in 2024, up from 5 percent in 2015

In 2015, data centres drew 1,238 gigawatt hours from Ireland’s metered electricity network, or 5 percent of all metered consumption. In 2024 they drew 6,969 gigawatt hours, or 22 percent, according to the Central Statistics Office release published on 10 June 2025. That share now sits above both categories of home: in the same year, the CSO found, urban households accounted for 18 percent of total metered electricity consumption and rural households for 10 percent. All three shares are measured against the same total.

A decade of quarterly readings

The CSO’s Table 1 records the climb without a break. The data centre share of metered electricity was 5 percent in 2015, 6 percent in 2016, 7 percent in 2017, 8 percent in 2018 and 9 percent in 2019. It reached 11 percent in 2020, 14 percent in 2021, 18 percent in 2022 and 21 percent in 2023, before the 22 percent recorded for 2024. In volume terms the series runs from 1,238 gigawatt hours to 6,969 gigawatt hours, an increase of about five and a half times, calculated from the CSO table.

The quarterly figures make the slope sharper still. Data centres used 290 gigawatt hours in the first quarter of 2015 and 1,829 gigawatt hours in the final quarter of 2024, an increase of 531 percent across the run of quarters.

In the most recent year of the series, data centre consumption rose 10 percent, from 6,335 gigawatt hours in 2023 to 6,969 gigawatt hours in 2024. All other users — residential customers and other business customers combined — rose 3 percent over the same period. Total metered electricity consumption in Ireland grew 30 percent between 2015 and 2024, from 24,600 gigawatt hours to 31,903 gigawatt hours. Arithmetic on the same table shows where that growth came from: consumption by all other customers rose about 7 percent across the decade, while data centres accounted for roughly 5,731 gigawatt hours of the 7,303 gigawatt hour increase, or nearly four-fifths of it.

A broader category in the release, large energy users — which typically includes larger data centres — reached 31 percent of total metered consumption in 2024, at 9,897 gigawatt hours, 9 percent up on the previous year. The companion Metered Electricity Consumption release, published the same day, puts total electricity consumption up 4.3 percent in 2024 against 2023, and records a median residential consumption of 3,246 kilowatt hours across 2.2 million residential meters, up from 3,174 kilowatt hours in 2023.

Finding a data centre among 2.5 million meters

None of this comes from a ready-made list, because data centres are not separately classified in the source data. The CSO’s background notes state plainly that “there is no agreed definition of a data centre”, and that data centres were not readily identifiable in the meter data. The raw material is meter data supplied by ESB Networks, covering all meters connected to the mains network. To build the series, statisticians examined around 2.5 million meters to identify the meter point reference numbers primarily used for data centre activity.

The identification runs on thresholds and cross-checks. The CSO matched names and aliases of known data centres consuming more than 0.5 gigawatt hours; looked at customers located in specific business parks above the same threshold; and reviewed all meters consuming more than 1 gigawatt hour annually. Published reports, the CSO Business Register and internet searches were used alongside those steps. The notes add two cautions worth carrying forward: a small number of data centres accounted for most of the consumption, and figures for all years are subject to revision, partly because a new data centre may use little electricity at first and sit below the search thresholds.

Commenting on the release, Dr Grzegorz Głaczyński, a statistician in the CSO’s Climate and Energy Division, said the data centre share of metered electricity consumption “grew substantially” from 5 percent in 2015 to 22 percent in 2024.

What the regulator did about it

The same growth has reshaped connection policy. On 23 November 2021, the Commission for Regulation of Utilities issued CRU/21/124, a direction to the system operators on processing data centre grid connections. The decision identified an “evolving, significant risk to electricity security of supply in Ireland”, and named the large increase in demand from the growth of the data centre industry as a significant contributory factor. The CRU directed EirGrid, as transmission system operator, and ESB Networks, as distribution system operator, to assess data centre connection applications against set criteria. It chose those connection measures over a moratorium, a step the regulator later described as one that would have been disproportionate.

That direction has since been superseded for new applications. On 12 December 2025 the CRU published a connection policy decision for large energy users requiring new data centres to provide new renewable and dispatchable electricity generation. Setting out its reasoning, the regulator noted that Ireland’s total electricity demand “has grown by 30% over the past 10 years, with data centre demand having greatly contributed to this level of growth” — in line with the 30 percent growth in total metered consumption between 2015 and 2024 in the CSO table.

The long count, then, rests on ESB Networks meter data, sifted by the CSO and tallied quarter by quarter for a decade. In 2015, data centres took 5 percent of Ireland’s metered electricity, and every other customer on the network took the remaining 95 percent. In 2024, data centres took 22 percent — 6,969 gigawatt hours — while consumption by all other users rose about 7 percent across the same ten years.