National Energy System Operator: Blackout Risk

Debate between Michael Shanks and Oliver Dowden

Wednesday 15th July 2026 Commons Chamber

[Michael Shanks]

I thank my hon. Friend for the way in which he has framed his remarks. He is right to say that these are incredibly serious allegations, and we take them with the seriousness with which they should be taken and will take on board any lessons learned. As for his point about the importance of grid investment, we inherited a grid that was not only in dire need of investment, but had not been designed to meet the full needs of generation that had been built for many years and not connected. We are currently constraining renewable energy that has been built over the past few years because it had not been connected to the grid. We are doing that work to ensure that the grid can continue to do what it needs to do.

As for my hon. Friend’s final point, let me state very clearly that electricity supplies were maintained throughout the June heatwave. No customer demand was subject to disconnection. Statutory frequency limits were maintained throughout the event, and the largest credible loss that could have occurred was also covered. Let me explain exactly what we mean by the margin in this instance. The margin represents the cushion of spare generation above the peak demand that is maintained by NESO, and at no point did we come close to breaching that. It did not indicate any kind of emergency situation. Demand was met, and those are the facts.

[Sir Oliver Dowden (Hertsmere) (Con)]

When I was in government we conducted one of the largest exercises, Exercise Mighty Oak, which involved more than 4,000 people testing the effect of a power outage. That exercise demonstrated that it cascaded very rapidly and that it very rapidly affected water supply, transport and other public services. Will the Minister confirm that he has had an opportunity to read the findings from that exercise, and can he update the House on what point the Government have reached in implementing its recommendations?

[Michael Shanks]

I pay tribute to the right hon. Gentleman, and to all who were involved in that incredibly important exercise. I was not aware of it at all until I came into this job and read the full report, as well as the breakdown of all the actions that had been started during his time in office and have been continued by officials now. As he says, the cascading impacts of a national power outage are extraordinary and very quick, which is why we are first investing in the grid to ensure that that remains a very low risk on the national risk register, and secondly taking forward all those actions. I do not have the detail in front of me, but very few of the actions remain open; most have now been completed. We are also, across Government, continuing to organise exercises—on a much smaller scale—to ensure that Ministers are prepared and that we continue to keep on top of the actions, because these are not one-time events. The water industry, to which the right hon. Gentleman rightly referred, must continue to look at preparedness. That is the wider work that we are taking forward on resilience.