National Grid posts profit growth as data centre demand surges in UK

National Grid has announced underlying operating profit of £2.3 billion ($3 billion) for the first half of 2025, up by 13% on the previous half year, driven by strong performance across regulated businesses.

The results from National Grid are the last under the leadership of John Pettigrew, who retires this month: he will be replaced by Zoë Yujnovich who was previously at Shell.

Pettigrew said: “Our financial performance reflects another period of strong operational delivery in line with our five-year financial frame. We continue to deliver for our customers, investing a record £5 billion this half, and we are on track to invest over £11 billion this year. 

“This investment in our networks is critical to ensure continued resilience, enable economic growth, deliver cleaner energy, and meet growing power demand. It’s been a privilege to lead National Grid through a significant decade of growth and I’m confident that under Zoë Yujnovich’s leadership, National Grid will continue to deliver for our customers and stakeholders.”

Indeed, Yujnovich takes over leadership of the utility giant at a time of surging demand on the power grid in the country, driven largely by new connection requests from data centres.

According to Pettigrew, who spoke during a conference call on the utility’s results, approximately 2.6% of all demand in the country comes from data centres, projected by NESO to potentially increase to 9% by 2035.

“What we’ve seen over the last 12 months is quite a surge of requests for connections to the transmission network to support data centres and generative AI.

“In our RIOT3 plans our assumption is that were expecting to see demand growth of around about 19GW… we’re going to build the network out to support that.”

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According to Pettigrew, this comes to approximately 4% demand growth per annum, “and about half of that is assumed to be for data centre demand and that’s backed up by the connection agreements that have been signed in the time frame for RIOT3".

“We feel comfortable that we’ve got a reasonably good handle on what the demand is going to do over the next five years or so and a reasonably good handle on what’s been expected in terms of growth in data centre demand and where it will connect. 

“National Grid is working with the government through the AI Council to really identify where are the best locations in the UK to locate those data centres, based on where their access [is], their capacity today or where the time frames for connections would be shorter than in other places, which is an important determinant for data centres.”

According to Ofgem, since November 2024, there has been a sharp increase in demand connection applications "far exceeding even the most ambitious forecasts for demand".

Specifically, said the UK's energy regulator, between November 2024 and June 2025, the demand queue rose from 41GW to 125GW. 

According to Ofgem, data centres account for a significant share of growth in the demand queue. This includes a mix of credible data centre projects with the potential to unlock value for consumers and citizens, as well as less viable projects that may crowd out those with  merit and block progress for those behind them in the queue. 

Ofgem says it is turning focus to demand connection reform and, in collaboration with government, NESO, and network operators, are exploring a regulatory levers to enable timely and efficient connections for demand projects.