We’re told that supermarket fridges are a significant climate change problem:

Supermarket fridges should be closed, campaigners have said, as it emerges that the appliances use up one per cent of all UK electricity.

Believe as much of that as you wish. It’s this assertion which is problematic:

Her brother, 28, told the Mail on Sunday: "I happened to be in a restaurant and they had given me a plastic knife and fork, so I was in an environmentally conscious mood. In the corner of my eye I saw a fridge and it was open, and I just thought that couldn't be very environmentally friendly.

"I think people are very happy to sacrifice convenience for the environment and that is the same with plastic as well."

If people were happy to sacrifice convenience - or anything else - for the environment then we’d not have a climate change problem. Because, given that humans at least attempt to maximise utility - the economists’ pet name for happiness - we would already have increased our happiness by having so sacrificed.

Our actual climate change, as with so many other environmental, problem is that people aren’t happy to do so.

Another way of making the same point, if we were all happy then there’d be no need for any laws on the subject, would there? No one would have to be forced into anything.

Which is also why the correct answer is, as ever, that carbon tax. No, leave aside whether there’s a problem in the first place. Assume there is. The carbon tax then makes explicit to us all, through the price system, the costs of whatever convenience or anything else we gain. Faced with actually having to pay for it we then all decide whether we’re happy to or not.

That is, if our problem is that we simply don’t know those costs but would be happy to avoid them if we did know, then the carbon tax is the pure complete and only necessary climate change solution.

To complete the logical trifecta here:

A Friends of the Earth spokesperson added: “With the world in the midst of a climate emergency our shops and stores should make it a top priority to save energy and slash the emissions that are roasting the planet.

“Supermarkets must ensure that their fridges and appliances operate to the highest energy efficient standards – and if they won’t, the government should make them.”

That we must be forced to means we’re not all happy to do so, doesn’t it?