The data centres
Approximately 40m high, with a combined footprint of up to 65,000m² — about nine reference football pitches. Rooftop plant and flues add height.
Explore the height Compare the footprintBUCKINGHAMSHIRE · PUBLIC INFORMATIONTHE SDC M40 CAMPUS PROPOSAL
3 data centers and extensive power infrastructure
M40 Campus
What you need to know
Proposed between Beaconsfield, Gerrards Cross and Hedgerley Village.
Here is what’s planned, and what’s still to be decided.
Understand the scale.
Make up your own mind.SDC photomontage · Original digital source, page 25
Footpath CSP/35/1 · Scenario 1, technology solution 1B
View full-resolution image & key
Make up your own mind.SDC photomontage · Original digital source, page 25
Footpath CSP/35/1 · Scenario 1, technology solution 1B
View full-resolution image & key
THE PROPOSAL IN 60 SECONDSAn industrial-scale campus.
An industrial-scale campus.
On Green Belt land.
Three 40m data centres covering about nine football pitches, a possible 200 MW gas energy centre and up to 216 backup generators, all proposed for Metropolitan Green Belt land beside the M40.
The gas energy-centre option
Scenario 1 includes on-site gas generation. Scenario 2 connects directly to the transmission grid without that energy centre.
Understand the power options Explore the campusThe backup generators
Up to 72 per building, for supply failures and testing.
See the generator count When would they run?01 / A different order of scaleHEIGHT STUDY / 01
Up to 180m tall.
Ringed by conservation areas and the Chilterns.
Buildings of about 40m, backup chimneys up to 66m, and energy-centre chimneys modelled at 140–180m
The data centre campusOne numerical scale · energy-centre height reference unspecified
Current flue estimate
66m
To the top of the flues.
Backup-generator stacks are currently estimated at up to 66m above ground. Their final height is still being tested.
+26m
above a 40m building in this comparison
Building envelope Backup flues Energy-centre modelling range
Source: SDC’s Community Consultation Environmental Report, pp. 10, 12 & 33.
Terrain, bunding and planting are excluded; this is not a view from a real location.
Local views / Developer illustrationsIndustrial buildings.
Industrial buildings.
Seen for miles.
Explore SDC’s published photomontages from 14 local viewpoints. Compare the power options from the same location.
B
Footpath CSP/35/1
Looking southwest
Proposed views, not photographs. Outlines show maximum heights.
How to read these images
Outline versus illustrated design
The maximum envelope shows the extent within which a design could fit. The illustrated technology option may occupy less of it. Read the flue, building and hidden-view lines against the original key.
A screen is not a calibrated view
The pack provides specific print sizes and viewing distances. Cropping, zooming and screen sizes change presentation. Use the original pages for those instructions; the pack also notes presentation limitations for extended panoramas.
Proposals can change
These are SDC’s September 2026 consultation illustrations. Technology, final design and planting performance remain subject to further work.
Read the visualisation methodology02 / The space on the ground
65,000 m²
The buildings alone.
The maximum combined building footprint is about 9 football pitches, using a 105 × 68m reference pitch.
The calculation
65,000 ÷ (105 × 68) = 9.10 pitches. This is a reference rectangle, not a claim that all football pitches have the same dimensions.
03 / The campus and its infrastructureThree data centres.
Three data centres.
And a power station.
Alongside the buildings: substations, battery storage and, in one scenario, a gas energy centre of about 200 MW. Five power layouts are still on the table. Only one will be built, and the consultation doesn’t say which.
300 MWapproximate maximum IT load
~200 MWgas capacity, Scenario 1
216potential backup generators
Ask SDCWhat are the maximum permitted operating hours of the gas energy centre?
SDC illustration, p.13. Indicative only.
Inside the data centres300 MW of electricity in.
300 MW of electricity in.
300 MW of heat out.
Nearly all the power a data centre uses ends up as heat, day and night. At full load that is power-station levels of heat, and it has to go somewhere. SDC says cooling is likely to be mainly by air, with some water cooling at peak demand “within the confines of the available water supply”.
Ask SDCHow will the heat be removed, how much water will cooling use, and will any heat be reused locally, for example to warm homes?
Servers
Networking
Distribution
Cooling
UPS & batteries
Backup power
04 / Power, around the clockNearly a fifth of the current UK’s data centre capacity.
300 MW
Nearly a fifth of the current UK’s data centre capacity.
On one site.
Approximate maximum IT load, the power drawn by the computers alone. Cooling adds more.
How big is that?
300 MWthis campus, IT load only
~1.6 GWall UK data centres operating today, across about 190 sites
~8 MWthe average UK site, by the same figures
Where would 300 MW come from?
Gas pipeline
≈ 200 MW energy centre
Electricity
Data centres
Heat & cooling
An on-site gas energy centre (about 200 MW) powers up to two buildings until more grid capacity arrives, which SDC expects around 2040. It could then run as a peaking plant.
The energy centre in contextWhat does 200 MW
What does 200 MW
look like nationally?
Compare the proposed energy centre with UK generating plants closer to its capacity. Fuels and operating patterns differ.
0–500 MW · linear scale
Proposed energy centreAll bars use the same scale
Select a station to explore the comparison.200 MW compared with
Spalding Expansion
67%
The proposed energy centre has about 67% of this station’s published capacity.
Open-cycle gas turbine · expansion plant only, excluding the adjacent CCGTOperator’s capacity figuresOur power strategySDC M40 Campus · Developer proposalScenarios 1 and 2 · Checked 25 September 2026Read original source ↗UK power station capacitiesRWE · Operator-published capacitiesGrimsby 40 MW; Cowes 140 MW (diesel); Great Yarmouth 411 MW; Didcot B 1,440 MW. Operator-published capacities. Dedicated Little Barford page gives up to 750 MW gross, used in the comparison. · Checked 25 September 2026Read original source ↗Spalding Energy Expansion capacityInterGen · Operator-published capacity300 MW open-cycle gas plant, operational since 2019; excludes the adjacent combined-cycle plant. · Checked 25 September 2026Read original source ↗King’s Lynn capacityRWE · Operator-published capacity382 MW combined-cycle gas plant, from the operator’s decarbonisation overview. · Checked 25 September 2026Read original source ↗
Ask SDCWhat is the total site demand including cooling, and when would a grid connection be secured?
05 / Backup power
216 diesel engines.
Enough to run the campus alone.
72 per data centre, on standby if the mains fails, so servers and cooling keep running. Diesel is SDC’s worst-case assumption; engines and fuel aren’t chosen yet.
DATA CENTRE 01 72 units
DATA CENTRE 02 72 units
DATA CENTRE 03 72 units
Ready
Silent, until the mains fails.
The normal supply does the work. Separate from the gas energy centre in section 4.
Normal supply
Generators on standby
Servers & cooling
Worst case in SDC’s own report
72 hours. All 216 running at once.
The report finds possible breaches of health-based air limits (p. 33), and calls them acceptable because the event is short and unlikely. That’s the developer’s view, not an Environment Agency approval.
Ask SDC
How many hours a year would the generators be tested, and how many at once? The Environment Agency’s guidance is under 50 hours, one at a time.
06 / Living alongside itNoise that never stops.
Noise that never stops.
Day or night.
Cooling fans, pumps and transformers never switch off.
On quiet nights, a steady hum or tone can carry further and matter more, and SDC hasn’t yet said how far.
Listen
What it could sound like.
All at once.
Illustrative audio. Fans, a transformer hum and plant rhythm layered together. Synthesised, not a recording of this site or a prediction of what you’d hear at home.
- Fans steady wash
- Transformers low hum
- Plant repeating rhythm
Combined sample15-SECOND SAMPLE
00 / 15sIllustrative waveform
Volume
Start with your device volume low.
What can this tell me about real noise?
This sample layers steady, tonal and fluctuating sound. It does not reproduce the proposed equipment, its loudness, distance, night-time conditions or mitigation. Speakers, headphones and volume settings change what you hear; small speakers may not reproduce low tones well.
A reliable site demonstration would need measured equipment spectra, operating assumptions, background sound and a validated acoustic model for a stated listening location. This player has no calibrated decibel level.
Real recordingWhat neighbours of a
What neighbours of a
US data centre hear.
NBC News report from a US data centre.
Playing the video loads it from YouTube.
A gas turbine is a jet engine.
Bolted to the ground.
Gas turbines work the same way as the engines on a passenger jet: they suck in air, squeeze it, burn fuel in it and blast the hot gas through a turbine. Instead of pushing a plane, the spinning shaft drives an electricity generator.
SDC hasn’t chosen the technology yet. Its options include gas engines, turbines, or a mix of the two.
Ask SDCIf turbines are chosen, how loud will they be at the nearest homes, day and night?
What SDC says
SDC says noise modelling is ongoing and identifies silencers, enclosures and other mitigation.
Ask SDC
How far will the campus be audible at night, and at which homes?
07 / What goes into the airNitrogen dioxide and fine particles.
Nitrogen dioxide and fine particles.
Bad for lungs and hearts.
Gas and diesel engines release nitrogen dioxide and fine particles, both linked to harm to lungs and hearts. How much reaches homes, schools and wildlife depends on how long the engines run, how hard they work, the weather and the chimney design.
NOₓ / NO₂ Combustion-related gases; nitrogen dioxide is regulated for its health effects.
PM₁₀ / PM₂.₅ Inhalable particles around 10 or 2.5 micrometres and smaller.
CO₂ A greenhouse gas produced by burning fuels such as natural gas and diesel. A different issue from local particle concentrations.
Other exhaust gases Combustion can also produce carbon monoxide and unburnt hydrocarbons; amounts depend on the fuel, engine and controls.
A sense of particle size
Human hair
≈ 70 µm
≈ 70 µm
Size comparison only.
Read the emergency case separately.
The 72-hour emergency case is explained in the backup section.
08 / A long construction horizon9+ years.
9+ years.
Not one building season.
SDC describes a programme of no less than 9 years, starting in 2028 if consented, but also gives approximately 2035 as the earliest completion.
Those dates do not clearly reconcile. Residents should ask for a consistent programme, including overlapping phases.
2028 · anticipated start2031 · first operation2035+ · earliest completion cited
Groundworks & access
Phased data centres
Energy infrastructure
Deliveries & site traffic
Overlap only, not phase dates.
Traffic, dust, vibration, earthworks, noise and temporary lighting are potential effects requiring controls. SDC proposes construction access from the A40 and a management plan.
09 / Screening takes timeOn completion.
On completion.
Fifteen years later.
Planting takes time to establish. Drag directly across the image to compare SDC’s completion and year-15 illustrations; both include the proposed development.
On completionYear 15Drag on the image · arrow keys also work
What remains visible? Compare the roofline and flues as well as the planting. These are the developer’s assumed outcomes, not a guarantee of future screening. Scenario 1, technology 1A is held constant.
What SDC says
SDC proposes excavating building platforms, planted embankments and retained vegetation to reduce visibility.
What residents should scrutinise
What do the views show before planting matures? What remains visible, and how will planting be maintained or replaced?
10 / After darkDark fields today.
Dark fields today.
What about tomorrow night?
A campus this size needs security, vehicle and construction lighting. In open Green Belt countryside, every light counts. Ask where it points, when it runs, and how glow would be kept off the sky.
Illustration only, not a lighting prediction.
SecurityAll night?
VehiclesWhich routes?
ConstructionWhat hours?
DayDuskNight
11 / Put it in contextRead the landscape.
Read the landscape.
Layer by layer.
Explore the developer’s original plans for the land, infrastructure and surroundings. Each map keeps its own boundaries and key.
Infrastructure designed
to operate for decades.
3
hyperscale buildings
40mapproximate maximum height
65,000m²maximum combined footprint
300MWapproximate maximum IT load
216potential backup generators
200MWapproximate gas capacity, Scenario 1
9+years in SDC’s programme statement
Read the proposal alongside its assumptions: the final design, operating conditions and predicted local effects remain central to understanding the scheme.