Data Centres and Data Transmission Networks

More Effort Needed

Nowhere in Europe has the growth of data centres collided with the electricity grid quite like it has in Ireland. Demand for digital services keeps climbing worldwide, and Ireland's position as a major European data hub — home to the European operations of many of the world's largest tech companies — means the country has felt that growth more sharply than almost anywhere else.

Data centres now account for 23% of Ireland's total metered electricity consumption, up from 22% in 2024 and just 5% back in 2015, according to the CSO. To put that in perspective, data centres now use almost as much electricity as every home in the country combined — homes accounted for 28% of national electricity demand in 2025.

Significant progress has been made on the policy side in the past year, with new rules from Ireland's energy regulator aimed at reining in the sector's impact on the grid. But further work on energy efficiency, grid capacity and the decarbonisation of electricity supply will be needed over the coming decade if Ireland is to hit its climate targets while continuing to host one of the largest data centre clusters in Europe.

Electricity Demand

Strong growth in computing efficiency has helped moderate energy demand from data centres globally, but that trend hasn't been enough to offset Ireland's runaway growth in data centre capacity. Metered electricity consumption by data centres rose 10% in a single year, from 6,973 GWh in 2024 to 7,663 GWh in 2025, according to CSO figures published in July 2026.

Quarterly CSO data tells the same story: data centre electricity use has climbed from just 291 GWh in the first quarter of 2015 to 1,991 GWh in the fourth quarter of 2025 — a near sevenfold increase in a decade. Most of that growth has been concentrated around Dublin, where the bulk of Ireland's data centres are located, putting significant strain on the local grid in particular.

CO2 Emissions

Ireland's Climate Action Plan sets a legally binding target of 80% renewable electricity by 2030. Data centre growth puts that target under real pressure: analysis shows that under a medium build-out scenario for data centre demand, the state would need to deliver around 700MW of new onshore renewable capacity every year through to 2030 — well above the 400–500MW a year Ireland has typically managed to deliver.

In the short term, some larger data centres have turned to on-site gas generators to meet their power needs directly, rather than drawing solely from the grid, effectively turning individual facilities into industrial greenhouse gas emitters in their own right. Getting data centre growth back in line with Ireland's carbon budgets remains one of the central tensions in the country's climate policy.

Activity

Emerging services and technologies — streaming, cloud gaming, blockchain, and above all artificial intelligence and machine learning — are the main forces pushing demand for data services (and the data centre capacity behind them) even higher. AI workloads in particular are far more energy-intensive than traditional cloud computing, and Ireland's role as a European base for major AI and cloud providers means this demand is landing disproportionately on the Irish grid.

Renewable Energy

Around 40% of Ireland's electricity came from renewable sources as of 2023, and tech companies operating data centres here are among the country's largest corporate buyers of renewable power, often through long-term power purchase agreements (PPAs) with wind and solar developers.

Under the Commission for Regulation of Utilities' (CRU) new connection policy, this is no longer optional for new entrants. Large data centres — those over 10 MVA — must now match at least 80% of their annual electricity demand with additional renewable electricity generation built in Ireland, on top of providing on-site generation or storage sized to their full grid connection. The aim is to ensure new data centre capacity brings new renewable generation onto the grid with it, rather than simply competing with homes and businesses for the existing supply.

Policy

Ireland's approach to data centres has shifted sharply over the past five years. In 2021, the CRU effectively imposed a moratorium on new data centre grid connections in the greater Dublin area, after EirGrid warned that unchecked demand growth risked triggering rolling blackouts. That freeze created years of uncertainty for both developers and the wider tech sector.

That uncertainty ended in December 2025, when the CRU published its long-awaited final decision on the Large Energy User Connection Policy, formally reopening the grid to new data centre connections under a stricter, tiered framework. Large schemes must now site in "unconstrained" parts of the grid, provide on-site generation or storage matched to their full connection capacity, and meet the renewable-matching requirement described above. On 1 April 2026, EirGrid followed up with a formal Grid Code Modification, requiring every new data centre connection to pass a System Stability Assessment confirming it can ride through — or quickly reconnect after — a fault on the electricity system.

Alongside this, the government's Large Energy User Action Plan (LEAP) sets out how the sector is expected to grow over the next five years in a way that's meant to be more compatible with grid stability and Ireland's climate commitments, following a Cabinet decision in January 2026 to approve continued data centre expansion under the new rules.

Private Sector Initiatives

Several of the world's largest cloud and tech companies operating in Ireland have made public commitments to power their local operations with renewable energy and to publish emissions data for their Irish facilities. Industry bodies representing the sector have also begun engaging more directly with the CRU and EirGrid on grid planning, though independent monitoring of how well these commitments are actually being met remains limited — something campaigners and researchers, including academics tracking Ireland's carbon budgets, continue to push for greater transparency on.