UK Regulator Threatens Fine Following Major Grid Failure

The near-simultaneous outage of a gas-fired power plant and a windfarm at rush-hour August 9 could see National Grid fined, depending on the findings of the investigation into the cause.

First, at about 1700 British Summer Time, the Little Barford gas-fired plant went offline and then a few minutes later the Hornsea Offshore wind-farm tripped. Supply to 900,000 consumers was affected, including a hospital and transport infrastructure.

Ofgem said it understood the frustration the power cut has caused and it has asked for an urgent detailed report from National Grid in order to understand what went wrong and decide what further steps need to be taken. This could include enforcement action, it said August 10.

The outages led to a drop in frequency and the automatic shedding of load to protect the rest of the system. But the load happened to include transport infrastructure, causing misery for the thousands trapped on trains. Traffic lights were also out of action. National Grid said the following day it had informed the energy regulator Ofgem that the system had been restored. 

National Grid said in an August 10 tweet that it welcomed the intervention by the government's Energy Emergencies Executive Committee, under Andrea Leadsom's Department for Business, Energy and Industrial Strategy, to "consider the incident and how it played out and we will work closely with that investigation to ensure that learnings can be reflecting in industry processes and procedures going forward." It said the Electricity Supply Operator [part of Naional Grid] has already begun its internal review and is collaborating closely with Ofgem, local distribution network operators and the affected power stations to understand the cause.

Commenting on the event in LinkedIn, corporate affairs manager of Alfa Energy Jeremy Nicholson said National Grid has "serious questions to asnswer." While it is too early to be sure of the cause, he said "attention was focusing on the lack of inertia from conventional generation at a time of very high wind output – a predictable situation that is set to become increasingly common in future. Did the ESO take adequate measures to ensure system stability? Should greater availability of battery storage and other very fast response technologies have been contracted in advance to maintain frequency and reduce the risk of disconnections? Ofgem and consumers will await their repot with great interest."