B is now for blackout – but how will this backstop be solved?

Utility Week magazine editor Suzanne Heneghan considers what next for the energy system following Britain's biggest blackout in a decade earlier this month

The energy sector got a new “b” word to think about this month, thanks to what is now simply being dubbed “the blackout”.

Brexit may still loom large, but it has been the power outages of 9 August exercising the industry ever since.

While we await National Grid ESO’s full report, the surge of questions about the biggest UK power cut in a decade continues. As does speculation about what it might signal for the future shape and operation of the country’s fast-evolving energy system.

On the plus side, the system worked in terms of isolating the area affected. But it would be wrong to be unconcerned about the two unexpected outages at Hornsea and Little Barford. It also wasn’t the plan that 500MW of embedded generation would then go offline, or that further units at Little Barford would then follow.

Criticisms levelled at National Grid about the disruption to commuter travel feel misplaced: this was a separate, train system design and operation issue.

But there’s no escaping the fact that it was the transmission network that was impacted by lightning, and the consequences of this were felt by power plants that went off the system
as a result.

If we ask, could such a consequence of events happen again, then the answer must be yes. And is it likely to get worse as our generation fleet changes? Yes, again.

As one industry source characterised it, we’ve moved away from having very few, very large, but very stable generation sources, where the chance of two going offline at the same time was remote.

Meanwhile, it is well known that a sharp change in the rate of frequency on the system (such as can be caused by lightning strikes) is a problem for wind and solar farms, which are designed to trip out under such conditions.

The more dispersed our system gets, the greater the chances are that more than one piece can go wrong at the same time. So, despite the blackout encroaching into our summer conversations, the time is right for inquiries and wider debate.

This should go far further than a probability and cost-benefit analysis about what our minimum reserve should be – it now feels highly unlikely this will remain only as a requirement to cover the largest single unit of generation on the system.

The national conversation should equally include transport, hospital generators, services allowed on interruptible contracts, as well as the robustness of regulatory standards.

In the end, as a public good issue, this will be a political decision and one with enduring consequences.

So, just like Brexit then.

Suzanne Heneghan, editor Utility Week magazine

suzanneheneghan@fav-house.com