Nobody publishes how much of the computing in Irish data centres is AI, so how many are "AI data centres" is unknown; operators report energy to a confidential EU database. What is known: data centres used 7.7 TWh in 2025 (CSO, published 7 July 2026), and a current AI rack draws about 132 kW (HPE, 2025).
HPE product page 'NVIDIA GB200 NVL72 by HPE', 2025
0
Planning applications we track that describe an AI facility
of 156, by description
Ireland's big campuses were mostly built for cloud computing and social media before the current AI boom. Since 2024, operators with at least 500 kW of IT load report energy and water to a confidential EU database (see the EU reporting rules), so the split between AI and other computing is not public.
An AI campus needs far more power per rack, and under the CRU's December 2025 rules any new one must bring its own dispatchable generation and match 80% of its demand with new Irish renewables.
How much power AI hardware draws
Figure 1
From one AI chip to every Irish data centre
A current AI rack draws 132 kW, about the electricity of 275 Irish homes. AI halls need far more power per rack, and liquid cooling, than ordinary cloud halls.
Each step up the ladder multiplies power: one H100 chip is rated at 700 W, an 8-chip server at 10.2 kW, and a 72-chip Blackwell rack at 132 kW. Ireland's biggest single campus by measured grid draw, Microsoft Grange Castle, averaged 154.5 MW in 2025, and all Irish data centres together averaged 875 MW in 2025. The scale is logarithmic, so equal distances mean equal multiples. No Irish or EU body publishes how much of that power is used for AI.
EstimateHomes per rack = 132 kW × 8,760 h ÷ 4,200 kWh (CRU typical home). Racks per campus = average draw ÷ PUE 1.54 (Uptime global average) ÷ 132 kW; an illustration only.
Anatomy of a data centre, and where each number is measured
Power flows grid → substation → batteries → servers → heat. Each headline number is taken at a different point, which is why megawatts, MVA, MW thermal and PUE can't be compared directly.
Electricity arrives from the transmission grid, passes through an on-site substation whose contracted maximum import (in MVA) is the "capacity" in grid debates, then through batteries that bridge outages, to the servers in the data halls. The CSO's 7,662 GWh for 2025 is energy metered at the grid connection. PUE compares total power with power reaching the servers: the industry average is 1.54, meaning 54% extra for cooling and losses. Backup generators are rated by fuel input (MW thermal), roughly two to three times their electrical output, and need an EPA licence above 50 MW thermal; water is metered at the mains connection.
Unknown. No Irish or EU body publishes what the computing in Irish data centres is used for, and none of the planning applications we track describes itself as an AI facility.