Data Centre Air Quality Assessments
Specialist air quality consultancy for UK data centre planning applications — diesel standby generator emissions modelling, EIA chapters and GLA-compliant operational assessments by chartered environmentalists.
Air Quality Evidence for Data Centre Planning Applications
Data centres present a distinctive air quality profile. The cooling plant and IT halls themselves are electric and emit nothing locally, but every site of any size carries a bank of diesel standby generators — typically multiple 2–3 MW engines — needed for grid-failure resilience and routinely tested throughout the year. These generators are what local planning authorities, the Environment Agency and the GLA scrutinise during the planning process.
Malcolm Pounder CEnv MIAQM leads our data centre work personally. We model NO2, PM10, PM2.5 and SO2 emissions from generator testing regimes and worst-case prolonged-outage scenarios using ADMS or AERMOD, calibrated against local monitoring and PCM background concentrations. The construction phase — with its large excavation, structural concrete pours, mechanical fit-out and significant HGV movements — is assessed separately using IAQM 2024 dust methodology, and we cover NRMM Stage V compliance for projects within the GLA Low Emission Zone or where the LPA requires it.
We are accustomed to the planning expectations across the principal UK data centre clusters: West London and Slough (Heathrow, Park Royal, A4/M4 corridor), the M25 west belt, the M11 corridor towards Cambridge, and the emerging Manchester, Newport and Cardiff zones. Our reports speak directly to environmental health officers, GLA case officers and statutory consultees, and integrate cleanly with the wider planning, EIA and energy strategy submissions on a hyperscale or co-location project.
Whether you are at pre-application stage and need an early air quality steer for site selection, you are preparing a full planning submission, or you have received a regulation 25 request from the LPA, we can scope and deliver an assessment that satisfies the technical demands without slowing your programme.
Our Data Centre Air Quality Services
From early-stage feasibility advice to full EIA chapters and discharge of conditions — the full air quality package for data centre projects.
Standby Generator Modelling
ADMS / AERMOD modelling of diesel standby generator stacks, covering routine monthly testing, load-bank tests and worst-case full-outage operation. We calculate NO2, PM10, PM2.5 and SO2 annual mean and short-term concentrations at the nearest sensitive receptors and compare them against the UK Air Quality Strategy objectives and WHO guidelines.
EIA Air Quality Chapter
Full ES air quality chapters for hyperscale and co-location data centre developments, integrating construction-phase dust, NRMM Stage V emissions, operational generator dispersion modelling and cumulative effects with neighbouring schemes — written to satisfy LPAs, the GLA and statutory consultees.
GLA & London Plan Compliance
Air Quality Neutral and Air Quality Positive assessments aligned with London Plan policies SI 1 and SI 7, with full NRMM Stage V compliance plans for the Greater London Low Emission Zone. Emission limit demonstrations for new combustion plant under the GLA Energy Assessment Guidance.
Construction Dust & CEMP Inputs
IAQM 2024 dust impact assessments and air quality inputs to your Construction Environmental Management Plan, covering excavation, structural concrete pours, fit-out HGV movements and trackout. We can support discharge of construction-related air quality planning conditions as the build progresses.
Who Commissions a Data Centre AQA?
We work with hyperscale operators, co-location developers, planning consultants and EIA coordinators on data centre projects ranging from single-hall edge sites through to multi-hundred-MW campuses. Most schemes will need air quality input at multiple stages — site selection, planning, condition discharge and operational permit interface.
We can plug into existing project teams at any stage and tailor the scope to the planning context and EIA threshold.
- Hyperscale data centre operators
- Co-location developers
- Edge / regional data centre projects
- Planning consultants
- EIA coordinators
- Architects and M&E engineers
- GLA / London Plan submissions
- Slough, M4, M11 corridor schemes
Frequently Asked Questions
Do data centres need an air quality assessment?
Most new data centres require an air quality assessment as part of their planning application. This is driven by the diesel standby generators required for resilience — typically multiple 2–3 MW engines that emit NOx, PM10, PM2.5 and SO2 during testing and emergency operation — and by the construction-phase impacts of a large hall development. In London, the GLA Energy Assessment Guidance and London Plan policies SI 1 and SI 7 require air quality information for new data centres, and most LPAs in Slough, the Thames Valley, M11 corridor and other tech clusters now expect a detailed assessment as standard.
What pollutants are modelled for a data centre AQA?
The principal pollutants are nitrogen dioxide (NO2) and particulate matter (PM10 and PM2.5) from the diesel standby generators, plus sulfur dioxide (SO2) where ultra-low sulfur diesel is not used. We model annual mean and short-term (hourly, 24-hour) concentrations at the nearest sensitive receptors using ADMS or AERMOD, taking realistic testing regimes into account (typically 1 hour per generator per month plus occasional load-bank testing) as well as worst-case extended outage scenarios. Construction-phase dust impacts are assessed separately using IAQM 2024 methodology.
What is the GLA requirement for data centre air quality?
Under the London Plan, new data centres must demonstrate that they are at least air quality neutral and, where they are in an Air Quality Focus Area, that they make a positive contribution. The GLA Energy Assessment Guidance specifies emission limits for new combustion plant (including standby generators) and requires dispersion modelling to demonstrate compliance with annual mean NO2 and PM objectives at the nearest sensitive receptors. Stage V non-road mobile machinery is required during construction within the GLA NRMM Low Emission Zone.
Are emergency generators modelled or just operational equipment?
Both. Routine testing of standby diesel generators is the dominant operational air quality source for a data centre — the cooling plant itself is typically electric and not a direct emitter. We model testing schedules (commonly black-start tests, load-bank tests and monthly run-ups) plus the worst-case scenario of a prolonged grid outage where all generators run simultaneously. This pessimistic case is often the determining scenario for short-term NO2 concentrations and is what statutory consultees look for.
How much does a data centre air quality assessment cost?
Fees depend on the scale of the development, the number of generators, the sensitivity of the surroundings and whether the assessment forms part of a wider EIA chapter. A single-hall data centre AQA in a non-sensitive location typically falls in a lower price band than a multi-hall hyperscale campus in a residential area or AQMA. We provide fixed-fee quotes following a short scoping conversation.