StackPath Ireland

Ranking · measured grid draw, 2025

The biggest data centres in Ireland

Measured by average grid draw in 2025, the largest data centre in Ireland is Microsoft Grange Castle at 154.5 MW, followed by Amazon (AWS) Clonshaugh (144.4 MW) and Meta Clonee (135 MW), from EPA annual environmental reports. Amazon runs 7 of the top 12. Only 16 sites file these reports, so smaller campuses aren't ranked.

Updated 10 October 2026 · data build 2026-10-10 · how we know · corrections

Figure 1

Who uses Ireland's data-centre electricity

Amazon (AWS) alone drew about 49% of all data-centre electricity in 2025; the sites that report to the EPA account for 89%.

Data-centre electricity by operatorNational average data-centre draw 874.8 MW (2025). Amazon (AWS) 424.7 MW (49%), Microsoft 154.5 MW (18%), Meta 135.0 MW (15%), Google 26.0 MW (3%), Equinix 18.5 MW (2%), K2 Strategic 17.5 MW (2%); not in EPA reports 98.6 MW.AVERAGE GRID DRAW, 2025 · 100% = 875 MW (CSO)Amazon (AWS): 424.7 MW, 48.5% of the national averageMicrosoft: 154.5 MW, 17.7% of the national averageMeta: 135.0 MW, 15.4% of the national averageGoogle: 26.0 MW, 3.0% of the national averageEquinix: 18.5 MW, 2.1% of the national averageK2 Strategic: 17.5 MW, 2.0% of the national averageNot in EPA reports: 98.6 MW, 11.3% of the national averageAmazon (AWS)49% · 425 MWMicrosoft18% · 155 MWMeta15% · 135 MWGoogle 3% · 26.0 MWEquinix 2% · 18.5 MWK2 Strategic 2% · 17.5 MWNot in EPA reports 11% · 98.6 MW
Data-centre electricity by operatorNational average data-centre draw 874.8 MW (2025). Amazon (AWS) 424.7 MW (49%), Microsoft 154.5 MW (18%), Meta 135.0 MW (15%), Google 26.0 MW (3%), Equinix 18.5 MW (2%), K2 Strategic 17.5 MW (2%); not in EPA reports 98.6 MW.AVERAGE GRID DRAW, 2025 · 100% = 875 MW (CSO)Amazon (AWS): 424.7 MW, 48.5% of the national averageMicrosoft: 154.5 MW, 17.7% of the national averageMeta: 135.0 MW, 15.4% of the national averageGoogle: 26.0 MW, 3.0% of the national averageEquinix: 18.5 MW, 2.1% of the national averageK2 Strategic: 17.5 MW, 2.0% of the national averageNot in EPA reports: 98.6 MW, 11.3% of the national averageAmazon (AWS): 49% · 424.7 MWMicrosoft: 18% · 154.5 MWMeta: 15% · 135.0 MWGoogle: 3% · 26.0 MWEquinix: 2% · 18.5 MWK2 Strategic: 2% · 17.5 MWNot in EPA reports: 11% · 98.6 MW

The bar is the national average data-centre draw in 2025: the CSO's 7,662 GWh divided by 8,760 hours, 875 MW. Each operator's slice is the sum of the average grid draw its EPA-licensed campuses reported for 2025. Only campuses with at least 50 MW thermal of on-site generators file these reports, so smaller sites and colocation halls sit in the light "not in EPA reports" slice. The two sources use different meters and scopes, so read the operator shares as close approximations, not exact percentages.

EstimateOperator shares divide EPA-reported draw by the CSO national average (StackPath, 3 Oct 2026).

Sources: EPA annual environmental reports, 2025, 3 Oct 2026 · CSO MEC02, 7 Jul 2026

Ranked by measured grid draw, 2025

Microsoft Grange Castle154.5 MW
Amazon (AWS) Clonshaugh144.4 MW
Meta Clonee135 MW
Amazon (AWS) Cruiserath76.6 MW
Amazon (AWS) Grange Castle South61 MW
Amazon (AWS) Blanchardstown49.8 MW
Amazon (AWS) Belgard, Tallaght45.6 MW
Amazon (AWS) Greenhills Road, Tallaght34.6 MW
Google Grange Castle South26 MW
Equinix Blanchardstown18.5 MW
K2 Strategic Ballycoolin17.5 MW
Amazon (AWS) Drogheda12.7 MW
#CampusCouncilGrid MW 2025Footprint haEst. rates
1Microsoft Grange CastleSouth Dublin154.519.5€12.4m
2Amazon (AWS) ClonshaughDublin City144.48.3€6.6m
3Meta CloneeMeath13514.9€9.9m
4Amazon (AWS) CruiserathFingal76.64.2€1.9m
5Amazon (AWS) Grange Castle SouthSouth Dublin612.1€3m
6Amazon (AWS) BlanchardstownFingal49.83.2€0.7m
7Amazon (AWS) Belgard, TallaghtSouth Dublin45.63.3€2.4m
8Amazon (AWS) Greenhills Road, TallaghtSouth Dublin34.62.8€3.8m
9Google Grange Castle SouthSouth Dublin262.3€5.6m
10Equinix BlanchardstownFingal18.51.5€0.5m
11K2 Strategic BallycoolinFingal17.52.8€2.9m
12Amazon (AWS) DroghedaMeath12.72.4€0.3m

Average MW drawn from the grid in 2025, from EPA annual environmental reports. Only sites with an EPA generator licence (≥50 MW thermal of on-site plant) file one, so this ranks 12 campuses; others are smaller or unreported. Footprint: OpenStreetMap. Rates: our estimate.

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