Yesterday, National Grid made its first emergency instruction since 2012, calling on industry to reduce its use of power. It was keen to stress that there was no chance of blackouts, and it was pointed out that 111 similar instructions were made between 1999 and 2008.

However, electricity capacity was certainly tight, and there has understandably been concern that Britain is facing an energy supply crunch. Yesterday’s squeeze on capacity was partly a result of low wind speeds, but the more significant issue was the unexpected breakdown of several ageing coal power stations.

These stations are, on average, 47 years old, and have stayed online far longer than was ever expected. They are inefficient and temperamental, as the situation yesterday evening demonstrated.

When peak demand came at 17:30, 35 per cent of the UK’s coal units were having major problems; 10 units were offline, and two were having problems ramping up.

We can no longer rely on our coal fleet to keep the lights on. We need a solid plan for replacing it. At IPPR we are undertaking a major project to identify how the UK can do exactly that by bringing forward innovative demand-side measures – which cut costs for businesses and consumers and help to manage the system more efficiently – and some new gas capacity which can top-up the system when required. The project is also unearthing the reasons why the government’s current attempts to incentivise these technologies is resulting in almost half a billion pounds of bill-payers money going to new diesel generators, as reported (£) on Wednesday.

One of the major barriers to bringing forward new energy investment is uncertainty over how long coal stations will be online. Everyone knows they will need to close, we just don’t know when. Some certainty over timings would, at a stroke, dramatically increase the chances of getting much-needed new capacity at a reasonable price. As previous research has shown, in the long term this would not only improve energy security but also cut people’s bills.

It seems counterintuitive to close power stations in response to a supply crunch, but certainty over the end of coal would secure both investment and our energy supplies.