‘Huge amount of work’ to get distributed black start ‘oven ready’

Developing the capability to restart the power grid using distributed energy resources will take “a huge amount of work”, according to director of operations at National Grid Electricity System Operator (ESO).

Speaking at a conference on the ESO’s Distributed Restart project – now in its second year of three years – Duncan Burt said although it may initially appear simple, the process is far more complex in reality.

“Black start will be one of the last bastions of large fossil fuel power stations on the system,” he told the audience. “At the moment, we regularly warm those stations and we buy contracts from them to keep them ready to go at a few hours’ notice if we ever have a shutdown.

“If we are going to get through our 2025 milestone, where we are regularly operating at very low levels of carbon and without fossil fuels, we need a whole range of alternatives to provide black start.”

Burt said the project should bring multiple benefits: “In short term, it gives us additional options that avoid producing carbon and running large power stations. It gives us an opportunity to restart local communities faster. And it helps us become much more resilient in the long term, with more electricity being used more broadly across the economy.”

But he also warned there is “a huge amount of work we need to do to get this oven ready.”

Distributed black start may require workers to travel to various generation sites around the country whilst also facing disruption to communication and transport infrastructure and power cuts in their own homes. “You’ve got all sorts of organisational, business, process, social factors going on,” he explained.

Burt said the key to success will be continuous trials and rehearsals so that if the system does go down “people don’t need to think. They can just do and act and know that things are going to work properly first time.”

At the same time, he said some things would inevitably go wrong, which is why the ESO plans to have “multiple options and multiple layers of defence”.

Eric Leary, a fellow speaker and head of transmission at project partner SP Energy Networks, said the challenges extend far beyond merely getting the first generators running.

Supply and demand will need to be balanced in order to maintain the stability of the fragile power islands that form. These islands will then need to be merged to restore power to the wider network.

He compared it to a high-wire act at a circus, adding: “We’ve got multiple things that will wobble around and interfere with each other. When we are growing this network, it’s not necessarily going to be a stiff high wire. The wire’s going to be moving around a bit. The people in the audience will be throwing things at us.”

Leary said batteries, with their ability to both produce and absorb power, are therefore likely to play an important role in the process. Although “a bit rough and ready”, he said balancing local supply and demand may nevertheless require network operators to cut some customers’ power supplies back off in “extreme cases”.

The Distributed Restart project was awarded almost £10.7 million of funding in Ofgem’s Network Innovation Competition for 2018. The first field trials are expected to begin this summer.