The UK’s biggest power cut in more than a decade has set alarm bells ringing – and the peal is being heard far beyond the immediate causes of the episode.
The UK Government has ordered an inquiry. So too has Ofgem, in the light of National Grid’s preliminary report, which suggested lightning triggered events that hit a million homes in England and brought hundreds of trains to a halt.
A bolt of awareness has hit government. Security of supply is not guaranteed and the
public is less interested in why things went wrong than in holding accountable those entrusted with keeping the lights on.
Power was lost from two generators – one at Little Barford gas plant and Hornsea One offshore wind farm. That took 5% out of the system. Power was quickly restored but it took hours to get trains going.
Whatever the explanation, there is good reason for a much wider ranging assessment of how resilient our power network is and, critically, is likely to become.
It is ironic that the question of intermittency from renewables is back on the political agenda since the August 9 episode as, whatever the reason for Hornsea One’s outage, it wasn’t lack of wind.
That is why it is essential to ask wider questions about resilience. Do we have enough power to cope when the wind does not blow and the sun does not shine?
The pace of change is rapid and – if I may be so immodest – a tribute to policies pursued in the early part of last decade. Incentivising renewables generation was crucial.
A decade ago, coal plants generated a third of the UK’s electricity, but in the first half of 2019, it was only 3% and, on 18 days, nothing at all.
I’m writing this on a windy day and a check on the Gridwatch site confirms the pattern – 29% of the UK’s electricity is coming from wind. Gas is at 36%, nuclear at 19% and coal at just 2%. Most of the rest is imported via interconnectors.
However, when the wind is not blowing, there still has to be enough back-up. That is the real resilience issue the UK grid faces.