An Coimisiun Pleanala
Ireland's national independent planning appeals body, deciding local and strategic infrastructure applications.
On 17 September, An Coimisiun Pleanala refused the €1.5bn Killala data-centre proposal after Mayo Data Hub lacked confirmed grid and renewable-power agreements.
Last refreshed: 24 September 2026 · Appears in 1 active topic
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Refused the Killala data centre
Data Centres: Boom and Backlash: Ireland refuses €1.5bn Mayo data centreBackground
Across Ireland, An Coimisiun Pleanala determines appeals against local-authority planning decisions and decides applications for strategic infrastructure and other major developments. Its REMIT places it between developers, local authorities and communities when projects require an independent national planning judgement.
Ireland relies on the body to examine whether substantial proposals meet planning requirements before they proceed. Decisions on infrastructure can shape the terms under which nationally significant development advances, particularly where local approval faces an appeal.
That independent appeals function gives An Coimisiun Pleanala an enduring role in Ireland's planning system. Its decisions matter beyond individual sites because they set out how evidence and planning policy are applied to major projects.
An Coimisiun Pleanala tightens evidence tests
On 17 September, An Coimisiun Pleanala overturned Mayo County Council's 2025 approval for a €1.5bn data-centre proposal at Killala, County Mayo. Its decision left the development without planning permission after the developer failed to show a confirmed grid connection or a renewable-power contract.
For An Coimisiun Pleanala, the ruling placed evidence of electricity supply and renewable procurement at the centre of its planning judgement. The 17 September decision demonstrates how the body can determine whether major infrastructure proposals have substantiated their power arrangements before construction proceeds.
