Google and Greystoke understate carbon emissions in UK AI datacentre planning
Developers for Google and Greystoke reportedly understated carbon emissions in planning documents for proposed AI datacentres in the UK by a factor of five, by comparing one year of emissions to a five-year carbon budget instead of year-to-year figures. If approved, the three projects together would account for more than 1% of the UK's 2033 carbon budget, equivalent to a mid-sized city's annual emissions.
What happened
Developers working for Google significantly misstated carbon emissions in planning documents for two proposed AI datacentres in Essex: a 52-hectare project in Thurrock and another at an airfield in North Weald. Planning documents stated the Thurrock site's emissions would represent 0.033 per cent of the UK's carbon budget between 2028 and 2032, when the correct figure is 0.165 per cent, and the North Weald site stated 0.043 per cent when the correct figure is 0.215 per cent.
Greystoke, planning to build a datacentre in north Lincolnshire, appears to have made the same error, stating emissions would represent 0.1043 per cent of the UK's carbon budget in 2033 when the correct figure is 0.5215 per cent. Experts at tech justice nonprofit Foxglove identified that in each case, developers compared one year of the proposed datacentre's emissions with the UK's entire five-year carbon budget, understating the significance by a factor of five.
Reported impact
Taken together, the three datacentre developments will account for more than 1% of the UK's carbon budget in 2033, equivalent to the emissions of a mid-sized city such as Bristol. The Thurrock datacentre will produce more emissions than an international airport, and Greystoke's site at peak output will emit one million tonnes of CO2 equivalent, just below the 1.2 million tonnes produced by all UK domestic flights combined.
Index analysis
The misstatements in planning documents appear to have made the environmental impact of the projects look five times smaller than it actually is, potentially misleading local councils and the public about the climate pollution the facilities will cause.
Governance controls
Greystoke responded that it expected to submit revised figures to the local planning authority as part of the planning process.
Classification
Sources and evidence
This record was researched and written by the Index, based on the following original reporting.