Yes, we must save the earth but orders to eat less and turn down the must be taken with alarge pinch of salt

SThis week he met members of Extinction rebellion — who received him coolly — and then backed yesterday’s report by the Committee on Climate Change (CCC), which demands Britain cut its emissions to net zero by 2050.

To manage this, the report says, we have to alter our behaviour dramatically by giving up red meat, replacing our gas boilers, abandoning petrol and diesel cars, and planting millions of trees on farmland.

Of course, climate change is a problem that needs to be addressed, and the public is generally supportive of efforts to cut carbon emissions — as it is of other measures that improve the environment, such as the Daily Mail’s plastic and litterpicking campaigns.

Already there have been great strides towards green energy, with a third of electricity generated by renewables last year.

But if the Government just leaps aboard every passing bandwagon, without thinking through what it is doing, it is in danger of imposing huge costs on the economy and causing considerable public resentment — while making emissions worse.

The fact is, if the public are to bear the cost of all this, we should be wary. For past evidence shows that good intentions can go horribly awry when the dead hand of the State is involved.

remember how the Blair government encouraged us to buy diesel cars in the name of cutting carbon emissions, only to find a few years later that high nitrous oxide pollution from diesel exhausts was worsening air quality? It meant that, through no fault of their own, people who’d bought diesel at the Government’s behest suddenly found the vehicles were being taxed out of existence and falling in value.

Smart meters, too, have been a farce, adding to consumers’ bills while doing little to cut energy consumption.

The point is that it is very easy for politicians to flaunt their green credentials and set targets — especially ones for many years after their political careers will have ended. It is a lot tougher working out realistic ways in which they are going to meet them.

LEAST the CCC’s proposed target on greenhouse gases, which you can be pretty sure will be adopted by the Government in the near future, is a lot more practical than the one proposed by Extinction rebellion, which demands zero emissions in just six years’ time.

Virtually no one in the energy industry thinks that is remotely possible, at least not without returning the country to a state of pre-industrial poverty.

Even so, the new target is a lot tougher than the one laid out in the Climate Change Act 2008 — which obliges the Government to cut emissions by 80 per cent, compared with 1990 levels, by 2050.

To be fair, some of the CCC’s proposals make sense — indeed, LED lightbulbs, which use only a tenth as much energy as traditional bulbs, are already becoming standard. Thanks to them, my electricity bills have halved.

But the CCC’s plan to remove carbon emissions entirely from our homes would mean ripping out gas boilers and replacing them with hydrogen boilers or heat pumps — air conditioning systems in reverse, which extract heat from the surrounding air or soil.

According to the Energy Saving Trust, a government quango, an air- source heat pump typically costs between £6,000 and £8,000 and a ground-source heat pump £10,000 to £18,000. That may be just about acceptable in new-build homes, but is a huge cost to impose on the home- owners whose existing gas boilers are working perfectly well, thank you very much.

The same is true of insulation, which the CCC demands we improve. Newly-built homes are already constructed with high levels of insulation, while 70 per cent of the 19 million British homes with cavity walls already have cavity wall insulation.

But it will be much harder to deal with the 8 million homes, mostly built before 1930, which have solid walls. According to the Energy Saving Trust, solid wall insulation costs an average of £7,400 if applied internally (which has the unfortunate effect of making rooms smaller) and £13,000 if applied externally.

In some cases it simply isn’t practical — cladding buildings with insulation can cause damp problems in old properties which, like mine, were built without damp-proof courses.

As for telling us to turn our thermostats down to below 19c, the Government is going to have to be extremely careful. It might be fine for those of us who enjoy good health, but until five years ago the Government was telling the elderly to heat their living rooms to 21c to avoid hypothermia. It now claims 18c is warm enough, a sudden change of view which hardly inspires confidence. What next? Will we have thermostat police?

Many will object, too, to the CCC’s demand that as a nation we eat 20 per cent less red meat, on the grounds that methane from sheep and cattle contributes to global warming.

It also demands massive treeplanting on farmland — eventually UDDENLY, the Government is falling over itself in order to make gestures on climate change. Last week, environment secretary Michael Gove grovelled before 16year-old Swedish schoolgirl Greta Thunberg, apologising that not nearly enough had been done to cut carbon emissions. AT increasing UK tree cover from 13 per cent of land surface area to 17 per cent. But why pick on the farming industry?

It doesn’t benefit the environment if we end up importing more food from the other side of the world. And it certainly won’t help the Government if all this pushes up food prices.

Phasing out all petrol and diesel cars, which Michael Gove has said he wants to do by 2040 — a date the CCC wants to bring forward to 2035 — may be possible, but it depends on rapid advances in battery technology. We would all have been driving electric cars by now were it not for two problems: they are very expensive and they drive for very limited distances before having to be recharged.

Technology might solve these problems, but it can’t be guaranteed. Electric cars may turn out to be like nuclear fusion power stations — which have spent the past 50 years being the potential answer to all our energy problems, without ever making the breakthrough.

Without the invention of unforeseen technology, it is going to be impossible for some industries to eliminate all carbon emissions. One of them is the airline industry. The CCC proposes these drastic cuts to emissions from our cars and our homes to compensate for emissions from aircraft.

But there is a serious issue of fairness here. Would it really be acceptable for owners of modest homes to be forced to pay through the nose to eliminate their carbon emissions so that the likes of Emma Thompson can continue to enjoy their transatlantic jaunts while lecturing the rest of us on our climate sins? Government ministers don’t exactly set a good example either, flying off to Davos to deliver lectures on climate change.

The point is that the Government needs to think very seriously before thoughtlessly committing itself willy-nilly to carbon reduction targets. Because there are unforeseen consequences everywhere.

We can, for example, stop burning coal in power stations — which the Government has vowed to do by 2025 — but we will need coal for steel-making because it is an essential ingredient of the manufacturing process. Equally, it is difficult to imagine how we will ever make cement without releasing a lot of carbon dioxide, because it is a pretty much inevitable byproduct of the process.

steel and cement, of course, we can’t have windfarms or solar farms, let alone roads, railways or large buildings.

The only way that Britain could eliminate carbon emissions from these two industries would be to drive them abroad (where, of course, the emissions would continue). Indeed, it is only thanks to the emigration of heavy industry from this country that the Government is able to boast that Britain has reduced carbon emissions by 40 per cent on 1990 levels.

When emissions are calculated on what is called a ‘consumption basis’ — which tots up all the global emissions spewed out in the cause of making things and providing services for people in Britain — our carbon emissions have fallen by around 10 per cent.

We could only ever go fully carbon-neutral if we have technology to suck existing carbon dioxide out of the air and bury it in the ground — a process known as carbon capture. Again, like electric cars, this is a technology which

might work in future. Many demonstration projects have been built, but as yet no one has managed to commercialise the technology, and it is not guaranteed that they ever will.

Of course, we should work towards lowering carbon emissions, preferably — eventually — to zero.

But setting targets without properly thinking through how you are going to achieve them is just playing political games.

If the Government wants to cut emissions, it is going to have to bring the people with it. It is not going to achieve that by hectoring us into living monkish lives — especially if ministers themselves carry on flying round the world in luxury from one climate change jolly to another. WITHOUT