The National Grid has unveiled plans to invest up to £35 billion ($44.1 bn) in the UK transmission system over the next five years.
The RIIO-T3 Business Plan includes a baseline investment of more than £11 billion ($13.87bn) to maintain and upgrade the UK's existing networks, alongside construction works for the first three Accelerated Strategic Transmission Investment (ASTI) projects. This is in addition to a pipeline investment of around £24 billion ($30.2bn), which includes £15 billion ($18.9bn) to increase network capacity.
The upgrade will include developing and delivering network reinforcement and expansion projects, including the 17 ASTI projects, and upgrading 3,500km (2,174 miles) of existing overhead lines, which, according to the National Grid, will double the amount of transferable power by 2029.
The investment will also support the connection of 35GW of new generation and storage and 19GVA (one billion volt-amperes) of large-demand customers such as data centers and gigafactories, and create a further 26GW of future connection options.
The plan notes that data centers will become the biggest driver of new demand connections for the first time. The plan projects the connection of 900MVA (Megavolt-Ampere) of new data center demand by 2029. MVA is a unit of apparent power that combines active power (MW) and reactive power (MVAR).
The National Grid believes that investment will support the decarbonization of existing sectors and the growth of new sectors, such as data centers, that support the greater use of artificial intelligence.
However, there are concerns that the dramatic increase in data center use could put undue strain on an already-constrained grid. The UK market is expected to reach 3.61GW by 2029, almost doubling its current rate. Subsequently, the UK government-owned National Energy System Operator has projected that annual data energy center consumption in the UK could reach as high as 35TWh by 2050.
Most of the UK's data center load is in London, representing around 80 percent of the country's data center capacity.
In March, the CEO of the National Grid warned that data center power use is set to grow dramatically. Speaking at the Aurora Spring Forum in Oxford, John Pettigrew said that the UK's energy industry had reached a "pivotal moment" and pitched developing an ultra-high-voltage onshore transmission network to meet the skyrocketing demand.
The UK's data center market has seen considerable investment over 2024. In October, four major US data center developers—Cloud HQ, CyrusOne, CoreWeave, and ServiceNow—announced plans to invest £6.3 billion ($8.22bn) in UK data center infrastructure.