Glossary - Naas Data Centres

A

An Bord Pleanála / An Coimisiún Pleanála: Ireland's national planning appeals board. If someone disagrees with a county council's planning decision, they can appeal to this body, which makes the final decision. It was renamed An Coimisiún Pleanála in 2024, so you'll see both names used depending on the document's date. This is who's currently deciding the appeal on P1 (Herbata) - see P1: Herbata.
An Taisce: The National Trust for Ireland - an environmental NGO and a prescribed body that planning authorities must consult on certain applications. It made a formal submission objecting to the P1 (Herbata) application and has published briefing material on data centre water use cited throughout this site.
Appropriate Assessment (AA) & Natura Impact Statement (NIS): A legally required check on whether a development could harm a protected wildlife site ("European Site" or "Natura 2000 site" - see below), even indirectly, e.g. via a stream. If a full assessment is needed, the applicant submits a Natura Impact Statement setting out the evidence and any measures to prevent harm.
Auto-producer connection: A type of grid connection where a large electricity user (like a data centre) can both draw power from the national grid and feed power back into it from its own on-site generation (e.g. gas turbines or batteries), rather than only ever drawing power.

B

BESS (Battery Energy Storage System): Large-scale battery installations, often housed in outdoor cabinets, used to store electricity for short periods - for backup power, to smooth out supply, or to feed power back to the grid at times of need. Herbata's application includes a BESS at every building; the Council's fire service raised detailed safety concerns about these in its Further Information request - see P1: Herbata.

C

Carbon budget / sectoral emissions ceiling: Ireland's legally binding limit on total greenhouse gas emissions over a set period (e.g. 2021-2025, 2026-2030). The national carbon budget is then divided into "sectoral emissions ceilings" - separate limits for sectors like electricity, transport, and the "commercial built environment." Which sector a development's emissions get counted against can make a big difference to how large its impact looks - see the carbon budget section of P1: Herbata.
Chief Executive's Order: The formal instrument a county council's Chief Executive signs to actually grant (or refuse) planning permission, giving legal effect to the planning department's recommendation.
Cloud, the: A marketing term for computing services - storage, software, processing power - that are delivered to you over the internet instead of running on your own device. When you save a photo "to the cloud," stream a video, or use an app that needs an internet connection to work, you're using someone else's computer sitting in a data centre, often hundreds of kilometres away. There's no actual cloud involved - it's a name for renting space on physical machines owned by a company like Microsoft, Google or Amazon.
Corporate Power Purchase Agreement (CPPA): A long-term contract where a company (e.g. a data centre operator) agrees to buy electricity directly from a specific renewable energy project (a wind or solar farm), often one built specifically to supply them. Developers use CPPAs to claim their operations are "renewably powered" - but critics point out that a CPPA doesn't reduce the company's electricity demand, and if the renewable project wasn't already built and operating for other users, a CPPA doesn't necessarily add any new clean power to the grid either.
CRU (Commission for Regulation of Utilities): Ireland's energy and water regulator. Among other things, it sets the rules for how large electricity users like data centres can connect to the national grid.
CSO (Central Statistics Office): Ireland's official national statistics agency. Its "Data Centres Metered Electricity Consumption" figures are the source for the widely-cited stat that data centres use 23% of Ireland's electricity (2025, up from 21% in 2023).

D

Data centre: A purpose-built facility full of computer servers that store data, run websites and apps, and provide the processing power behind "the cloud" (see above). They range from small server rooms to "hyperscale" campuses like the ones proposed for Naas - buildings the size of several football pitches, packed with racks of computers that run 24 hours a day and need constant cooling and a large, reliable electricity supply to do it.
Data hall: The part of a data centre building that actually contains the server racks and computing equipment - distinct from the administration offices, plant rooms, and other ancillary space in the same building.
Development Plan / Local Area Plan (LAP): A Development Plan is a county council's overarching land-use and planning policy document, reviewed roughly every six years. A Local Area Plan is a more detailed, smaller-scale version of the same thing for a specific town or area - the Naas LAP 2021-2027 is what currently zones the P1 and P2 lands exclusively for data centre use.

E

EIAR (Environmental Impact Assessment Report): A detailed technical report, required for larger developments, assessing a project's likely effects on the environment - covering things like air quality, noise, water, ecology, traffic and climate. It's prepared by the applicant's own consultants and submitted with the planning application.
EirGrid: The state-owned operator of Ireland's national electricity transmission grid (the high-voltage network that moves power around the country). Distinct from the ESB, which generates and supplies electricity, and from the CRU, which regulates the sector.
EPA (Environmental Protection Agency): Ireland's environmental regulator. It licenses large industrial water abstractions and, since the EU Energy Efficiency Directive, collects annual water and energy-use data from large data centres - though much of that data is kept confidential at the industry's request.

F

FDI (Foreign Direct Investment): Investment by overseas companies in Irish jobs, operations and infrastructure - technology and pharmaceutical multinationals are among the largest sources of it, and successive Irish governments have built industrial and tax policy around attracting and retaining it. FDI is a real and legitimate economic concern, and it's part of the backdrop to national debates like the disapplication of Section 15 of the Climate Act for named infrastructure projects. We think it's a weaker justification for approving a specific site's location than it is for supporting the sector generally - see our view on this.
Further Information (FI) request: When a planning authority reviewing an application isn't satisfied with the information submitted, it can formally request more detail or revisions before making a decision. This pauses the standard decision clock. Kildare County Council issued a Further Information request on the Herbata application in October 2024, raising serious concerns - see P1: Herbata.
First-party appeal / Third-party appeal: A "first-party" appeal is one made by the applicant/developer themselves (e.g. objecting to conditions attached to their own grant of permission). A "third-party" appeal is one made by anyone else - objectors, residents' groups, NGOs. Unusually, P1 (Herbata) was appealed by both.
Friends of the Earth Ireland (FOE): An environmental NGO and part of the international Friends of the Earth network. Its data centre briefing material, drawing on CSO, EirGrid and SEAI figures, is cited throughout the National context section of this site.

G

Gas turbine: OCGT vs CCGT: Both burn natural gas to generate electricity on-site. An Open Cycle Gas Turbine (OCGT) is simpler and quicker to start up but less fuel-efficient. A Combined Cycle Gas Turbine (CCGT) captures waste heat from the turbine exhaust to generate extra electricity (or supply heating), making it more efficient but more complex. Herbata's Further Information response swapped a number of OCGTs for CCGTs to improve efficiency.

H

Hyperscale: Industry term for data centres built at a very large scale, typically for major cloud/tech companies, as opposed to smaller enterprise or "edge" data centres.

I

Islanded data centre: A data centre that generates most or all of its own power on-site (typically via gas turbines) rather than relying primarily on the national electricity grid. Planning authorities have raised concern that these developments don't help decarbonise the wider energy system and can effectively shift the "security of supply" problem from electricity to gas. See P1: Herbata for how this played out at Herbata.

J

Judicial review: A High Court process for challenging whether a public body (like a planning authority) followed the law correctly in making a decision - it's not a re-run of the planning merits, only a check on whether the decision-making process was lawful.

L

Large Energy User (LEU): The regulatory category covering very high-demand electricity users, including data centres, which are subject to specific connection policies from EirGrid and the CRU because of their impact on grid capacity.

M

Material alteration / variation: The formal process by which a council changes a Development Plan or Local Area Plan outside its normal review cycle - the mechanism we're asking Naas Municipal District councillors to use to remove the P2 zoning. See our FAQ on precedent.

N

Natura 2000 site / SAC / SPA: EU-protected wildlife sites. A Special Area of Conservation (SAC) protects habitats and non-bird species; a Special Protection Area (SPA) protects wild birds. Together these form the "Natura 2000" network. Developments with any hydrological connection to one (e.g. via a stream) need an Appropriate Assessment (see above).
NGO (Non-Governmental Organisation): An independent, non-profit body not run by government - An Taisce and Friends of the Earth Ireland are the two most frequently cited on this site. NGOs have no formal decision-making power in planning, but many (including both of these) are statutory prescribed bodies that councils must consult, and they can also make submissions or take legal challenges like anyone else.

P

Planning condition: A requirement attached to a grant of planning permission that the developer must comply with - as opposed to refusing permission outright. Much of the P1 (Herbata) story is about serious objections being addressed through conditions rather than refusal - see P1: Herbata.
Population equivalent (PE): A standard measure used in wastewater engineering to size treatment plants - one "population equivalent" represents the amount of organic pollution one person typically produces per day, used as a common yardstick for adding up the load from households, businesses and industry together. A plant's capacity in PE isn't simply a headcount of residents connected to it; large commercial and industrial users (including, potentially, data centres) count too. See The Facts: Water.
Prescribed body: An organisation that planning law requires a council to formally consult on certain applications - e.g. Uisce Éireann, the HSE, Transport Infrastructure Ireland, or An Taisce (in specific circumstances). Their views are recorded but the council isn't bound to follow them.
Private Wires: Proposed Irish energy legislation that would let large electricity users - including data centres - build a direct ("private wire") connection to a generator, such as an on-site gas plant, bypassing the shared public grid. Supporters argue it takes pressure off grid capacity; critics, including Friends of the Earth Ireland, argue it lets large users lock in their own gas-fired power while avoiding the shared costs everyone else pays for grid upgrades. See Take Action.

R

Riparian buffer: A protected strip of land left undeveloped along the edge of a river or stream, to protect water quality and wildlife habitat.

S

Section 15 (Climate Act): The provision of the Climate Action and Low Carbon Development Act requiring public bodies (including county councils) to perform their functions "in so far as practicable" in a way consistent with national climate policy. See the dedicated page: The Climate Act, Explained.
Site notice: The physical notice a planning applicant must erect on the site itself, visible from the public road, informing the public that an application has been (or will be) lodged.
SuDS (Sustainable Drainage Systems): An approach to managing rainwater and surface water runoff from a development using natural methods - ponds, swales, permeable paving - instead of piping it all straight into drains, to reduce flood risk and pollution.

T

TII (Transport Infrastructure Ireland): The state body responsible for national roads and motorways, including the M7 - a prescribed body consulted on P1 because of the development's proximity to and works on the motorway.
Trade effluent: Wastewater from a business or industrial process - as opposed to ordinary domestic sewage - discharged to the public sewer network. Anyone doing this, including a data centre discharging cooling-system wastewater, needs a trade effluent authorisation from Uisce Éireann or an EPA wastewater discharge licence, the same regime that applies to any other large industrial user. See The Facts: Water.

U

Uisce Éireann: Ireland's national water utility (formerly Irish Water), responsible for public water and wastewater services, including the connections a data centre would need.

W

The Water Forum: An official statutory body that advises on water policy in Ireland and represents water users' interests. Its 2024 review of data centre water use, cited throughout the Water section of this site, was one of the first independent assessments to flag that peak data centre water demand coincides with periods of lowest water availability.

Z

Zoning: The land-use category a council assigns to a piece of land in its Development Plan or Local Area Plan (e.g. residential, industrial, agricultural). The P1 and P2 sites carry the zoning objective "P - Data Centre," meaning the Naas LAP currently states the Council "will not consider any alternative use on these lands" other than data centres. That's the specific thing our P2 campaign is asking to change.

Missing a term? If you came across a word or abbreviation on this site that isn't explained here, let us know and we'll add it.