At the end of last summer, with war in Ukraine still raging, the talk was of eye-watering energy price surges and power cuts, particularly in Germany, with its heavy dependence on Russian oil and gas. But now, Germany aims to reduce its Russian energy usage to almost nothing by year-end, delaying its closure of nuclear plants, cutting its energy usage, even reopening coal-fired power stations.

Meanwhile, the cross-border supply and storage of gas has been improved. The US now supplies nearly a third of Europe’s Liquid Natural Gas (LNG), and Europe has bought up supplies from round the globe, shipping them to new floating terminals in the North Sea. Now the gas price is down to pre-war levels.

A lot of this, however, is just a quick, emergency fix. Ukraine tells us the need to have a robust energy policy, and a flexible one, able to withstand interruptions in different energy sources. And it has taught us the need for investment in that.

But energy investment is a long-horizon activity. It can take 7-10 years to get your money back. So, investors need policy certainty — just the opposite of what our politicians are providing. There are frequent and unpredictable changes in taxation, like ‘windfall taxes’, for example. And equally unpredictable changes in regulation, such as price caps.

Then there is the general tendency of politicians to see one fad after another as our single energy solution. From coal we went to postwar ‘atomic power’, then cheap oil from the Middle East, then, after OPEC, North Sea gas (the proceeds of which we used to expand welfare dependency), then wind and solar, then fracking, then hydrogen, batteries and now fusion. Each new energy minister (and there have been a lot of them) seems to have their own fad. How is anyone to invest long-term in such a fickle policy environment?

Plainly there is a huge need for more electricity generation. Think of all the power needed by millions of electric vehicles, including buses, trains and even planes. We may even be manufacturing more as we wean ourselves off uncertain China. And we need more interconnectivity too. We need to route our energy around unknowable future events like wars, accidents, and policy stupidities. France might even need UK supply when its nuclear reactors need replacing soon.

To generate on that scale, we need investment, which means policy certainty. No stop-start tax, price and regulatory changes. And to make that generation robust against changing events, we need to have a wide mix of energy sources. Not a dash to one source, then another. Not just renewables — wind power, for example, is volatile and so needs back-up from other sources — but gas, nuclear and fracking as well, leaving open the option of new technologies if they work out, such as small-scale nuclear and fusion power. And a mix of competitive suppliers too — using nuclear technologies from the US, France and Japan, for example.

And new generation will need greater vision on land-use planning. Large-scale generation projects provoke large-scale NIMBYism. But they are appropriately national rather than local decisions. They are about national energy security, which must take priority. And if that means compensating unhappy locals, we should. Huge discounts on their future energy bills, perhaps? The prospect of energy diversity and security must surely be worth that.