Developers have submitted plans for a £200 million data centre on the site of Microsoft’s former UK headquarters in the Reading suburb of Earley, with the site intended to initially rely on natural gas fuel cells for power.

The proposed facility is intended to provide 72MW of compute capacity, requiring around 110MW of power at peak demand, including cooling and supporting infrastructure, but only 1.8MW of grid capacity is currently available, leaving a large shortfall.

Developers Mapeley, which bought the site from Microsoft in 2005, are planning to work around the constraint by installing 49.9MW of solid oxide fuel-cell capacity, providing about 42.55MW of effective power supply for the first phase, along with separate generators for emergency backup.

A 60MW grid connection has been secured from utility SSEN, but the reinforcement required to implement it is not expected until 2037.

Mapeley has said it would prefer to shift entirely to grid provision, but as a 110MW grid connection has not been secured, it is unclear when or if the site would be able to end its reliance on natural gas.

The developer said construction could take place from 2027 to 2031, involving the demolition of three office buildings at Thames Valley Park to be replaced by data centre halls reaching up to 100ft, or about the height of a 10-storey block of flats.

The application has been submitted to Wokingham Borough Council, with a decision expected by March.

Data centre provider Nscale has also considered solid oxide fuel cells for a proposed £2bn data centre in Essex amid delays to a planned 90MW grid link.

In July, UK energy regulator Ofgem began consulting on proposals for stiffer rules to stop speculative data centres from overloading the queue for grid connections, amid unprecedented connection demands from data centres seeking to power AI services.