Among other bits of advice The Carbon-Free Home recommends, unsurprisingly, that nothing should be left on standby.

The authors don’t much approve of devices whose function is merely to amuse: “Is there ever such a thing as an efficient use of a video console, or does it always represent a failure of imagination?”

Clothes should be left to dry in the sun, or at least in the air, because tumble driers can use as much as 6kW.

Indeed, “Appliances that use electric resistance heat must go.”

I can see what they mean.

The iron uses 3,250W, but have never been big on ironing.

The kettle uses a relatively modest 2,300W, so I decide henceforth to make my tea using a Storm Kettle, designed for camping, which boils a whole litre using just a few scraps of newspaper and two small sticks.

Alas, this is not fast – and with the heating off I’m in constant need of hot drinks.

Then there’s my wife’s hairdryer

This uses 3,250W, like the iron.

“Instead of using a hairdryer,” the book’s authors recommend, “get a less maintenance-intensive haircut, shower in the evening, or dry hair with a towel or in sunshine.”

They have obviously not met my wife, who has what she herself terms “bonkers” hair.

If she doesn’t blow dry it straight it goes weirdly frizzy, which is why she does that every morning at vast cost in energy and emissions.

I have tried to suggest that she might grow it a bit longer, so that the hair’s own weight pulls it into some order, but she refuses to believe it would work – something about split ends – and not being a hairdresser I’m in no position to judge.

I’ve refrained, for now, for suggesting that she eliminate the problem altogether by shaving it all off.

Mercifully, it turns out that we can make enormous savings without yet banning hairdryers.

Scientists estimate that roughly two thirds of the primary energy consumed today is wasted, usually in the form of heat that nobody wants or uses.

(Primary energy is the energy contained in a lump of coal, whereas “useful” energy is the light emitted by a bulb once the coal has been burned to make steam, the steam has powered a turbine, and the resulting electricity has been transmitted over the grid).

With currently available technologies we can reduce that waste significantly, according to the man who supplies electricity to my house.

In the early 90s, Dave Vincent was a hippy, living in an ex-military vehicle and surviving off-grid with his own minimal energy arrangements, including a tiny windmill.

It was this that gave him the idea that led him to drop back into the mainstream, where he set up the first wind powered electricity company in Britain, Ecotricity.

Today, Vince lives in a house with all the usual power hungry apps, fridges and freezers and so on, and he thinks it’s impractical to give them all up.

Instead, we should buy the most efficient models when upgrading and put as much as possible of our domestic load into evenings and even the middle of the night.

The national grid has massive spikes in demand – the classic case is the ad break in the middle of the World Cup Final, when everybody goes to put the kettle on.

To cope with these peaks, the grid has to run at a big surplus, and there’s also a lot of energy wasted by running the grid down when demand is low.

Some plants come on only to meet peaks, and they’re generally the dirtiest ones.

We could save a lot of energy if we flattened the peaks and troughs.

“If we put a chunk of electric demand into the night time,” says Vince, “we could save several hundred MW of capacity. It would be the equivalent of all the nuclear power, or about 20 per cent of the entire grid.

“I like to call this ‘intelligent demand’. At the moment we just have ‘on demand’.”

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