Last week the UK suffered a serious outage of power from the National Grid which affected almost a million people and brought the east coast rail network to a standstill. Social media is awash with many claims that the reason for this outage was the failure of wind power linked to the grid, with the implication being that as the UK becomes ever more dependent upon renewable energy the probability of serious power outages will only increase.
But is this an accurate assessment or pure scaremongering?
Well according to a senior official at the National Grid the answer is simply the latter. Duncan Burt, who is the director of operations for the National Grid Electricity system operator described it as an ‘incredibly rare event’ and when questioned in detail on Radio 4’s today program categorically clarified that the failure of Wind Power was a single element that on its own had no impact. It was the domino effect of multiple failures.
The outage was in fact triggered by two power stations, gas and then wind simultaneously disconnecting from the grid.
Mr Burt went on to explain that ‘The events we saw yesterday really have nothing to do with the changes in wind speed or variability of wind and that whilst there was severe weather on the network, that in itself is not unusual and that today we routinely operate the grid now at very high levels of wind power.’
Further learning from the incident will no doubt come to light if you can excuse the pun. Ofgem (the UK official energy watchdog) has insisted and commissioned an urgent report on the mass power failure.
The disruption to the UK was substantial, not only were many homes affected but Newcastle hospital, Ipswich hospital and the entire east coast rail network including the central London stations of St Pancras and Kings Cross were plunged into darkness.
Whilst Kings cross re-opened on Friday evening, delays continued well into saturday morning and were compounded further with high winds bringing down trees on the railway tracks.
“It was like witnessing something out of an apocalyptic film.
“No one knew what was going on and, given it’s a Friday afternoon, it’s the last thing you want to encounter.”
Newcastle airport was plunged into darkness and Network Rail said train signals had lost power over a large area including Newport, Gloucester, Ashford, Bristol, Eastbourne, Hastings, Three Bridges and Exeter.
The protection systems of the National Grid in actual effect worked as intended and protected the majority of the National Grid by cutting the power to a proportion of the grid following the simultaneous failure of both a gas fired power station and offshore wind farm.
“We think the system worked really well,” Duncan Burt, director of operations at National Grid, told BBC Radio on Saturday. “We’re already very confident that there was no malicious intent or cyberattack.”
Mr. Burt added that National Grid would seek to learn the lessons of Friday’s power failure. The company would look at whose power had been disconnected by the automatic protection systems, he said, and whether there was a way to minimize the impact of similar events in the future.
According to EnAppSys, a company responsible for the monitoring of the British Power Network, the gas-generating site that failed was Little Barford, in Cambridgeshire, this power plant that was commissioned in the mid 1990’s and that is operated by the German multinational energy company RWE. Hornsey One, was the wind farm that is based in the North sea that simultaneously failed. It opened in June this year and is described by its operator, the Danish company Orsted, as the largest offshore wind farm in the world.
The UK is today one of the most secure national grids in the entire world. The average UK consumer of electricity takes the provision of power as granted and serious blackouts have not been a regular occurrence since the miners strike of the 1970’s where the government was forced to ration coal and manage power supplies.
Last weeks power outage has however shown the UK’s dependency upon electricity and as the world moves further away from fossil fuels, not only in power generation itself but also in the electrification of cars, railways, homes and battery technology is the National Grid not only capable of providing the power but is it now, more than anytime in a generation more susceptible to power outages as it becomes ever more dependent on renewable power and wind energy.
Wind is unpredictable and the availability of wind energy is not constant. Wind energy is therefore not well suited as a base load energy source. If we had cost-effective ways of storing wind energy the situation would be different.
We can hope for breakthroughs in energy storage technologies in the future, but right now, wind turbines have to be used in tandem with other energy sources to meet our energy demand with consistency.
Prof Tim Green, Co-director of the Energy Futures Laboratory, Imperial College London, said:
“This event does not appear to be due to wind generation reducing owing to reduced wind speed. If that were the case there’d be reduction across many wind farms in the same area.
“The First generator to disconnect from the grid was a gas fired plant at Little Barford at 16:58. Two minutes later Hornsea Offshore wind farm seems to have disconnected. This would seem to be a technical failure/error. This might be linked to disturbance caused by first generator failing; might not. Will need to wait for National Grid’s full technical investigation to get to bottom of that.
“There was a lot of wind power today and consequently less gas used. A system with little gas plant running does need careful management because when generators fail the frequency responds more quickly.”
The good news is that the majority of the National Grid system continued to function and there was not systemic failure. As such the failure of the system in a small part can be viewed as a success is as much as the defence measures operated as intended.
However there are some concerns and some relevant questions moving forward. With wind power becoming an ever larger contributor to the national grid the potential for frequency drop also increases. With a smaller load from traditional power stations the reliability of the base load and margin for failure also diminishes so the system has more potential to fail than in any point since the 1970’s.