Why don't data centres show up in planning searches?
Search Ireland's planning registers for "data centre" and you get a list. It is incomplete. 24 of the campuses our directory shows as operating have no planning record that uses the words "data centre" at all.
Applications use other words. Examples confirmed in the files:
- "Electrical rooms for electronic operations": the phrase on applications at or next to Amazon's sites on Belgard Road and Greenhills Road in Tallaght (SD16A/0093, SD14A/0232), and at the Hexagon Building in Blanchardstown (FW13A/0067).
- "ICT facility": three buildings, 66,630 m², with 20 generators each, at Kish Business Park, Arklow (Wicklow 20/1088), later amended to five buildings and an energy centre.
- A warehouse converted to an "energy centre" with 12 generators "to power 2 data storage buildings" (Fingal FW22A/0257).
- Warehouse space changed to "data storage use" in Clonshaugh (Dublin City 3640/21, withdrawn).
Our reading. Much of this is standard planning language rather than concealment. "ICT facility" is how many development plans describe the use. But the effect is the same: residents, councillors and journalists searching for data centres don't find them.
How we found them
We trained a classifier on the 131 applications we already knew were data centres. We removed the obvious words, such as "data centre", so it had to learn from everything else: the other vocabulary, floor areas, generators, and location (distance to a 220 kV substation or a known campus).
In cross-validation it ranked known data centres almost perfectly (ROC AUC 1). We then read the top-ranked applications we had not already labelled, one by one.
| Top-ranked new applications read | Confirmed | Likely | Precision (confirmed only) | Precision (incl. likely) |
|---|---|---|---|---|
| 10 | 9 | 1 | 90% | 100% |
| 25 | 21 | 2 | 84% | 92% |
| 50 | 37 | 6 | 74% | 86% |
| 60 | 44 | 6 | 73% | 83% |
One campus, many records
Count buildings and Microsoft Grange Castle is 12 data centres; count EPA licences and it is 3; count planning files and it is 26. We count it as one campus.
Microsoft Grange Castle in South Dublin is the campus with the most public records joined to it. OpenStreetMap shows 12 separate buildings, the valuation list rates 9 properties, 3 EPA licences cover its generator fleets, and 26 planning files describe its halls, extensions and amendments (9 of them found only by our planning-register model because their descriptions never say "data centre"). Every one of those is a legitimate thing to count, which is why published totals for Ireland range so widely. A campus is the unit that matches how operators build and how the grid connects them.
Sources: StackPath directory, 10 Oct 2026 · OpenStreetMap contributors (ODbL), 10 Oct 2026 · EPA LEAP, 3 Oct 2026 · Tailte Éireann valuation list, 3 Oct 2026 · Council planning registers, 10 Oct 2026
What it changed
The search widened our planning set to 156 applications, gave 2 operating campuses their first planning record, and surfaced a new campus at Kish Business Park, Arklow. The campus count and planning statistics on this site include them.
It also matters for anyone quoting "the number of data-centre planning applications". Counts built from keyword searches undercount, and they undercount the largest operators most, because those use their own house wording.
For councils, it is a practical problem. Development plans now set conditions on data centres: waste heat in Dublin City (CEE25), at least 30% renewables in Kildare (RE O72), and policies in South Dublin (EDE7) and Fingal (DMSO92). Those conditions only apply if planners recognise the application as a data centre in the first place.
Limits
The model ranks; people decide. Every application counted was read. The model is weaker at finding data centres in places with none yet: in the top 20 of that list, precision was 10%. A planning application is not a building, and our build-time analysis shows many permissions are never used.