Utility Week

10 | 30TH AUGUST - 5TH SEPTEMBER 2019 | UTILITY WEEK Policy & Regulation News As policymakers and regulators continue to probe Britain's biggest blackout in a decade, some are calling for a fundamental review of the energy system. We round up some key industry reaction so far. T he public may have to consider paying for more backup power in order to prevent a repeat of the 9 August blackout, energy experts have warned following publication of a preliminary report into the incident by National Grid Elec- tricity System Operator (ESO). The power cut le nearly a million people without power and severely disrupted many commuters' homeward journeys when trains were le stranded. The report confirmed early reports that the blackout was triggered by a lightning strike on the Eaton Socon, Wymondley Main transmission circuit (see story on facing page). The snowball effect Immediately a er the strike, the report said, the Hornsea offshore windfarm and Little Barford gas power station reduced supplies to the grid, taking 1.4GW of generation off the grid. Professor Tim Green, co- director of Imperial College London's Energy Future Lab, told Utility Week the incident raised questions about resilience and the public's appetite for funding it. He said: "To have two large generators falling off the system 'National conversation' now needed over cost of resilience pretty much simultaneously is an exceptionally rare event. While the power cuts were obviously very frustrating for those hit by them, the reaction was pretty impressive and a lot of the knock-on problems were not actually anything to do with low-frequency demand discon- nection (LFDD). "In terms of whether National Grid is holding the right level of reserve, when the power cut hap- pened it was holding just over 1Gw and it looks like at least 90 per cent of that came good. "If the decision is taken that we need to double that, you're looking at close to £300 million a year. If you spread that over 25 million customers, that's £12 a year. Long-term, do people want to invest in the system to that level, to prepare for the worst case scenario? Perhaps we need a national conversation." He said the blackout was a "rare occurrence" and it was "ill-informed" to think you could entirely guard against something similar happening again. More reserve Thomas Edwards, senior model- ler at Cornwall Insight, agreed that more reserve capacity, like batteries and gas plants, may be needed if it is judged that similar power cuts must be avoided. While National Grid was holding 1GW of response capac- ity, the overall loss of transmis- sion-connected generation was more than 1.3Gw. "There is a balance here between the likelihood and scale of potential distribution and the amount consumers might be prepared to pay to avoid this in our increased digitalised age," Edwards said. "The investigations will need to evaluate the way National Grid assesses response and reserve given the changing mix of generation on the system and how services are provided and contracted for, including the liabilities on providers unable to fulfil their obligations." DB "To have two large generators falling off the system pretty much simultaneously is an exceptionally rare event." PROFESSOR TIM GREEN, IMPERIAL COLLEGE LONDON

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