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
A closer look at what’s proposed
Three data centres.
Major power infrastructure.
Proposed between Beaconsfield and Gerrards Cross. Here is what’s planned, and what’s still to be decided.
The proposal in 60 secondsThe proposal & source
The data centre campusSDC M40 Campus · Developer proposalDimensions, generators and cooling · Checked 25 September 2026Read original source ↗
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
Start here / the proposal in 60 secondsThree parts.
Three parts.
One proposed campus.
Three data centres, plus the electricity, cooling and backup systems to run them. The power strategy is still being developed.
The gas energy-centre option
Scenario 1 includes on-site gas generation. Scenario 2 connects directly to the transmission grid without that energy centre. Only one scenario would be delivered.
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
The roofline is only
part of the story.
The flues rise well above the roofline.
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. House height is an illustrative assumption. Terrain, bunding and planting are excluded; this is not a view from a real location.
Height sources
Building and flue heights — Community Consultation Environmental ReportSDC M40 Campus · Preliminary developer design and modellingPage 10: buildings approximately 40m; backup stacks estimated up to 66m above ground. Page 12: energy-centre stacks modelled at 140–180m (reference level not specified in this passage). Page 33: final stack heights still to be determined. · Checked 25 September 2026Read original source ↗
Local views / Developer illustrationsWhat would change
What would change
from this viewpoint?
Explore SDC’s published photomontages from 14 local viewpoints. Compare the power options from the same location.
B
Footpath CSP/35/1
Looking southwest
These are proposed views, not photographs of a completed development. Outlines indicate the developer’s maximum parameters; some show structures hidden or filtered by the existing scene.
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 groundA change in perspective
65,000 m²
The buildings alone.
The maximum combined building footprint is about 9 football pitches, using a 105 × 68m reference pitch.
That excludes the surrounding roads, substations, energy infrastructure and landscaping.
Source
The data centre campusSDC M40 Campus · Developer proposalDimensions, generators and cooling · Checked 25 September 2026Read original source ↗
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.
Area comparison rounded to nine whole pitches. These rectangles do not show the site layout or the proportions of the proposed buildings.
03 / The campus and its infrastructureOne campus.
One campus.
Shared power, cooling and backup.
Explore the developer’s indicative campus drawing, then compare what could occupy the power-infrastructure area.
Compare the five indicative power layouts
One area. Alternative power strategies.
What changes between the options?
Only one power scenario would be delivered. The three Scenario 1 illustrations show alternative gas-generation technologies; Scenario 2 shows alternative substation designs.
Scenario 1 · Gas generation
Hybrid · layout one
The energy centre occupies the power-strategy area. The final gas-generation technology is still being considered.
Compare the published elevationsOriginal SDC illustration, p.13. Buildings, landscape and power layouts are indicative. Public rights-of-way keys are available on the original page.
Inside the data centresComputers turn electricity into work.
Computers turn electricity into work.
And heat.
Server racks run continuously. Cooling removes their heat; batteries and backup systems help keep them operating through interruptions.
Servers
Networking
Distribution
Cooling
UPS & batteries
Backup power
04 / Power, around the clockComputing on an
300 MW
Computing on an
industrial scale.
Approximate maximum IT load across the campus. IT load measures power used by computing equipment.
Source
The data centre campusSDC M40 Campus · Developer proposalDimensions, generators and cooling · Checked 25 September 2026Read original source ↗
Power is not the same as annual energy
MW describes a rate of power use. MWh describes energy used over time. The IT figure excludes additional facility demand such as cooling. No household-equivalent claim is made here.
Where would the power come from?
Gas pipeline
≈ 200 MW energy centre
Electricity
Data centres
Heat & cooling
One option uses an on-site gas energy centre to supply up to two buildings. SDC anticipates wider grid capacity around 2040; it then assumes the energy centre could operate as a peaking plant.
Source
Our power strategySDC M40 Campus · Developer proposalScenarios 1 and 2 · Checked 25 September 2026Read original source ↗
How does a gas engine or turbine generate power?
Gas is supplied to the plant through a pipeline.
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 figuresCapacity is a rate of generation, not yearly output, size, emissions or noise. Selected examples, not a ranking. The 300 MW campus IT load is a separate figure.
Capacity sources and comparison limits
Figures follow each linked operator source and may use different net/gross conventions. SDC’s net/gross basis is unspecified. Spalding Expansion excludes the adjacent combined-cycle station. Cowes is diesel-fuelled. Final technology and operating hours may differ.
SDC’s ≈200 MW proposal
Our power strategySDC M40 Campus · Developer proposalScenarios 1 and 2 · Checked 25 September 2026Read original source ↗
RWE station capacities
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 Expansion
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
King’s Lynn capacityRWE · Operator-published capacity382 MW combined-cycle gas plant, from the operator’s decarbonisation overview. · Checked 25 September 2026Read original source ↗
05 / The infrastructure behind resilienceOne symbol = one potential generator
72 per building.
Up to 216 in total.
Three groups of standby generators, for supply failures and testing.
Source
The data centre campusSDC M40 Campus · Developer proposalDimensions, generators and cooling · Checked 25 September 2026Read original source ↗
DATA CENTRE 01 72 units
DATA CENTRE 02 72 units
DATA CENTRE 03 72 units
Current design assumption, subject to refinement. The count does not imply continuous operation. Read below for fuel, testing and emergency assumptions.
How backup power works · assessment assumptionsWhat does
What does
“backup” mean?
A backup generator is an engine connected to an electrical generator. It burns fuel to make electricity when the normal supply fails, helping keep servers and essential cooling running.
Diesel generators? Diesel is the fuel assumed in SDC’s worst-case air-quality modelling. That is an assessment assumption; the report does not establish the final engine and fuel specification.
SDC’s generator and testing assumptions
Backup generators and operating assumptionsSDC M40 Campus · Developer assessment assumptionsCCER printed pp. 10 and 32–33: 216 units; diesel assumed for worst-case air-quality modelling; monthly and annual testing; all generators operating for 72 hours in a total-supply-failure scenario. · Checked 25 September 2026Read original source ↗
Ready, on standby
The normal supply does the work.
The backup generators are kept available for loss of the normal electricity supply. They are separate from the proposed gas energy centre described in section 4, which could supply routine power under Scenario 1.
Normal supply
Generators on standby
Servers & cooling
Equipment status by operating mode; this is not a power-flow or wiring diagram.
Standby does not mean emission-free.
While running, diesel engines produce nitrogen oxides, particles, carbon dioxide and other exhaust gases, as well as noise and vibration. Fuel, load, running hours and controls determine the amount.
Explore air quality ↗Explore sound character ↗
Combustion emissions
Combustion emissions explainedEnvironment Agency · Official technical guidanceEmissions to air from fossil-fuel combustion, including nitrogen oxides, particulate matter, carbon dioxide and carbon monoxide; other pollutants depend on fuel and technology. · Checked 25 September 2026Read original source ↗
What the project report actually says
The emergency case needs its own explanation.
On page 33, SDC reports potential small exceedances of human-health air-quality thresholds in the 72-hour emergency scenario. SDC argues that these would be acceptable because the event is short and unlikely, and concludes that significant adverse human impacts are not expected. This is the developer’s assessment; the passage is not an Environment Agency approval.
The report also explores selective catalytic reduction (SCR), an exhaust treatment that reduces nitrogen oxides. This remains under consideration and can release residual ammonia, which also needs assessment for sensitive habitats.
Read the qualifications · pp. 33, 40–41
Emergency emissions and mitigation qualificationsSDC M40 Campus · Developer assessment, not regulatory approvalCCER printed p. 33: possible small human-health threshold exceedances in the 72-hour emergency case, considered acceptable by the developer. Printed pp. 40–41: SCR and ammonia-slip considerations; final controls under development. · Checked 25 September 2026Read original source ↗
How should testing and emissions be controlled?
Environment Agency guidance for applicable emergency diesel installations calls for testing to be minimised, below 50 hours per year, and one engine at a time. It also advises against testing during poor air quality and requires emissions-optimised engines or suitable exhaust treatment. This guidance does not establish SDC’s final test schedule or permit conditions.
Environment Agency · emergency diesel guidance
Emergency backup diesel engines: best available techniquesEnvironment Agency · Official guidanceScope-specific guidance on engine emissions and testing: minimise tests, less than 50 hours annually, one engine at a time, avoiding poor air quality. Not SDC-specific permit conditions. · Checked 25 September 2026Read original source ↗
The details still to establish
Which engines and fuel, how long each test lasts, how many units run together, and which noise and exhaust controls would be secured.
06 / Living alongside itNoise has
Noise has
character.
Fans, pumps, transformers and generation equipment can create different kinds of sound. Night-time background levels, tones, intermittency and duration all matter.
Source
Noise and vibration managementEnvironment Agency · Official guidanceSound character and noise assessment · Checked 25 September 2026Read original source ↗
Listen to the character
Three sounds.
Three different experiences.
Illustrative audio. These are synthesised examples, not recordings of this site or predictions of what you would hear at home.
A steady, broad wash15-SECOND SAMPLE
00 / 15sIllustrative waveform
A synthetic fan-like sound. Listen for the continuous wash of air, spread across many frequencies.
Volume
Start with your device volume low.
What can this tell me about real noise?
These samples demonstrate steady, tonal and fluctuating sound. They do not reproduce the proposed equipment, its loudness, distance, night-time conditions or mitigation. The examples are not matched for perceived loudness. 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.
What SDC says
SDC says noise modelling is ongoing and identifies silencers, enclosures and other mitigation.
Source
Environmental approachSDC M40 Campus · Developer assessment summaryAir quality, noise and ground conditions · Checked 25 September 2026Read original source ↗
What residents should scrutinise
Does the assessment address sound character as well as overall levels, especially at night and when several sources operate together?
07 / What goes into the airHow long they run
How long they run
matters.
Fuel, engine load, running time and exhaust treatment determine emissions. Weather and stack design affect concentrations at homes and sensitive habitats. Routine power, testing and emergency operation need separate assessment.
Which pollutants are involved?
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.
Environment Agency · combustion emissions
Combustion emissions explainedEnvironment Agency · Official technical guidanceEmissions to air from fossil-fuel combustion, including nitrogen oxides, particulate matter, carbon dioxide and carbon monoxide; other pollutants depend on fuel and technology. · Checked 25 September 2026Read original source ↗
Source
Air quality statisticsDefra · Government evidenceNitrogen dioxide and particulate matter · Checked 25 September 2026Read original source ↗
A sense of particle size
Human hair
≈ 70 µm
≈ 70 µm
Diameter comparison. No concentration or health effect is depicted.
Source
Particulate Matter BasicsUS Environmental Protection Agency · Official science explainerParticle sizes and human hair reference · Checked 25 September 2026Read original source ↗
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.
Source
Site access, transport and constructionSDC M40 Campus · Developer forecastConstruction programme and access · Checked 25 September 2026Read original source ↗
2028 · anticipated start2031 · first operation2035+ · earliest completion cited
Groundworks & access
Phased data centres
Energy infrastructure
Deliveries & site traffic
Conceptual overlap only. Bar lengths do not predict individual 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.
The proposal in sectionScreening starts
Screening starts
with the ground.
Follow the developer’s section drawing from the existing terrain to the proposed earthworks and planting.
SDC section toward Moat Farm
The land today
The dotted line records the existing landform in SDC’s section toward Moat Farm.
What SDC says
SDC proposes excavating building platforms, planted embankments and retained vegetation to reduce visibility.
Source
Landscaping and green spacesSDC M40 Campus · Developer proposalBunding, planting and nature trails · Checked 25 September 2026Read original source ↗
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.
Site & communities
Select a topic to change the original map. These are separate published plans, not precisely registered overlay layers. Zoom and scroll for detail.
Open SDC’s interactive mapInfrastructure 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.