Great British Grid: power certainty becomes a contract term

On 29 September the prime minister, Andy Burnham, used his speech to the Labour Party conference to announce Great British Grid, a new branch of Great British Energy. He called it “a publicly-owned company that will challenge the private sector operators” and said it would “speed up connections so businesses can expand and grow more quickly”. He put the problem in business terms: “You would not believe how many businesses complain to me they can’t get going because they can’t get connected to the grid.”

The Department for Energy Security and Net Zero (DESNZ) and Great British Energy published the detail the same afternoon. The release says Great British Grid (GBG) will invest public capital, alongside private money, in electricity network projects. Two further measures sit in the same release. The government will “bring forward reforms to expand self-build connections”, letting developers and businesses build their own connections “where appropriate, rather than waiting for network companies to do so”. It will also accelerate competitive tendering of transmission projects, with GBG among the organizations able to compete.

Ofgem’s own figures show how much of the connection problem is about data centers. According to the regulator’s consultation release of 29 July, contracted demand offers rose from 41 gigawatts (GW) to 125GW between November 2024 and June 2025, driven largely by data center projects. The same release puts data centers at around 73GW of the demand in the connections queue.

For the businesses that buy data center and cloud capacity, and the operators that sell it, the announcement needs a careful reading. A new grid company will not, by itself, connect a data center any faster. The measure that could change timelines is self-build, and it works by moving grid risk from the network company onto the developer. Buyers should respond by treating power certainty as a contract term rather than an assumption.

A new owner does not shorten the queue

The release is careful about what GBG is not. Its notes to editors say GBG will “complement, rather than replace” the existing institutions and that the role of existing network operators “remains unchanged”. Ofgem stays the economic regulator and the National Energy System Operator (NESO) keeps responsibility for operating, planning and coordinating the system. The release gives no budget figure. Start-up costs will be covered by Great British Energy’s existing budgets, and the long-term budget “will be considered as part of a future spending review”. It names no project, gives no date for GBG’s first investment and does not mention data centers.

The government’s own notes acknowledge that “grid delivery has a long development time”. A new bidder for transmission tenders may, over time, add competition and capacity. Nothing in the release changes the position of a project already waiting on a connection offer. The reforms that act on the queue sit elsewhere. The release credits work with NESO and Ofgem for removing more than 300GW of speculative capacity, and Ofgem’s July proposals would require large data center developers to put money down to hold their place.

Self-build moves the risk to developers

Self-build is the part with teeth. The release points to Ireland, where it says similar reforms cut connection times by up to 11 months. For a developer with a site, a customer and no connection date, that could be up to 11 months regained. The release does not say when the reforms will arrive, or which connections will qualify beyond “where appropriate”.

The trade-off is built into the idea. A developer that builds its own connection is no longer waiting on a network company, but it can no longer point to one either. The design, the contractors, the cost and any slippage become the developer’s problem and, through prices and terms, its customers’ problem. That comes on top of the money Ofgem proposes developers put down. Its proposed data center commitment fee ranges from £237,500 to £712,500 per megawatt (MW), paid on accepting a connection offer, refunded at energization and forfeited if the project leaves the queue early. For a hypothetical 50MW campus, that is between £11.9m and £35.6m. The consultation closed on 16 September, and Ofgem says responses will inform its final decisions.

At least one operator sees an opening. Andreas Rathmann, director, power and energy at CyrusOne, welcomed more competition in delivering power infrastructure in comments quoted by Data Centre Review. His summary of what the sector needs is also the buyer’s: “certainty that power will be available when required”.

Power dates belong in the contract

For buyers, the practical change is that the question of when the power comes on now has more possible answers, and more ways to go wrong. Before signing for new UK capacity, buyers should ask:

• Is the power for this capacity already energized, contracted with a date or only a place in the queue?
• Is the connection being delivered by the network company or self-built, and who carries a delay?
• What happens to the service date, the price and the right to exit if the connection slips?
• Will any Ofgem commitment fee, if adopted, be passed through in pricing?

Operators have the mirror-image job. Those with power in hand, or a self-build plan they can evidence, can price certainty as a feature and back it with service credits tied to the power date. Those relying on a queue position should say so in writing, rather than let a sales date stand in for a grid date.

Great British Grid may, in time, bring more competition to building the network. Until it does, the only power date a buyer can rely on is the one written into the contract.