Climate change – the practicalities

Although not covered by the national press at the time, we now know from the Sunday Times that students with tents, banners and placards occupied the 15th-century quad of St John’s College, Oxford on Wednesday, 29th January. They said they wouldn’t leave until the college agreed to sell its shares in those prolific producers of hydrocarbons, BP and Shell. The College is very rich. It was reported at the time in two student newspapers, but not it seems elsewhere. 

Dominic Lawson is a columnist for the Sunday Times and a climate change sceptic. He is also a Brexiteer, although his father, Nigel Lawson, a former Conservative Chancellor with similar views to his son, has lived in France for many years. So people I don’t really take very seriously.  On this occasion, however, I have some sympathy with the conclusion which Dominic draws from what happened.

It seems that on the day of their occupation, the protesters e-mailed Professor Andrew Parker (an eminent research scientist and the principal bursar) to demand a meeting to address their demands. These were that St John’s “declares a climate emergency and immediately divests from fossil fuels”. His answer was certainly original. “I am not able to arrange any divestment at short notice,” he wrote. “But I can arrange for the gas central heating in college to be switched off with immediate effect. Please let me know if you support this proposal.” When one of the demonstrators complained that he was being flippant, Parker replied to say that he was making a serious point: “It is all too easy to request others to do things that carry no personal cost to yourself. The question is whether you and others are prepared to make personal sacrifices to achieve the goals of environmental improvement (which I support as a goal).” The protest organiser, Fergus Green said: “It’s January and it would be borderline dangerous to switch off the central heating.” “Borderline hilarious, more like”, as my new best friend Dominic said.  The students gave up 3 days later, having received warm words from the Principal of the College, but not having achieved either of their aims.

It was just after this that the government announced that it would bring forward, by five years to 2035, the date by which we would no longer be allowed to purchase new cars that use fossil fuels, including hybrid vehicles. My car is 3 years old and I would normally expect to buy a replacement after say 5 years/50,000 miles.  I have been looking into the cost of electric cars and have to say that they are rather expensive. Even with the government subsidy, they seem to be at least £5,000 and up to £10,000 more than the petrol equivalent.  And then there is the question of the time to recharge them and the lack of a charging network. And if there were one, I’m not sure where we’d get the electricity from to power it.

There is also the somewhat difficult question of where, and at what cost in the widest sense, we get the materials to make all the batteries necessary to allow such a major change. Last June a group of scientists led by Professor Richard Herrington, the head of earth science at the Natural History Museum, sent a report to the Climate Change Committee of the House of Commons. It warned that to replace all cars on British roads with EVs, the batteries needed would require almost twice the world’s current yearly supply of cobalt, the total amount of neodymium produced globally every year, three-quarters of the world’s annual supply of lithium and at least half its copper supply.   Now obviously, we’re not looking at replacing all our cars in one year, but even to replace the vast majority over say a period of 10 years would place a significant strain on the earth’s mineral resources.  And that’s only for the UK.  If we count the rest of the world in, then the resource problem looks impossible to resolve.

And then there’s the question of our central heating systems.  We are told that they need to be replaced so as to avoid the need for the use of polluting ‘natural’ gas.  But with what?  In the UK, the idea of using solar panels is a little optimistic.  So then we have the possibility of electrically powered air source heat pumps.  They work rather like reverse fridges. The old Flanders and Swan song about the first and second laws of thermodynamics said: “You can’t move heat from the colder to the hotter without using energy”. What that implies is that the greater the difference in temperature between the colder and the hotter, the more the energy needed to move the calories along the heat gradient. Which in turn means that heat pumps work brilliantly in the summer, when they’re not needed, but not so much so in the winter. 

As they’re in fact air-conditioning units, but used in reverse, one might think that the technology has achieved maturity, so we cannot reasonably expect much of a price decrease when we all start using them.  Currently, a unit comparable to the normal gas boiler costs about £10,000 to buy and install. A lot more than a gas-fired boiler.  A smaller capacity air-pump would cost less, but not that much less, as the installation cost would be similar.  And then there’s the question of the radiators in the house.  We normally heat our radiators to about 75 C.  A heat pump works at a maximum temperature of about 55 degrees.  This means that our houses would take quite a long time to heat up.  We could instead install underfloor heating, but this is very costly. Or we could externally insulate all our houses to reduce the need for heat, but at the same time make them all look completely different. Imagine the outcry - “disfiguring the traditional face of Britain!”.

So then, altogether, in my humble opinion, we’re not going in the right direction at all.  With cars which simply can’t be made in the quantities required and with charging times that are either ridiculously long, or of a reasonable time - a few minutes - but which would hopelessly overload the supply grid.  And not only do we want to change our motor cars, we presumably wish to change the propulsion system for our lorries, vans, container ships, cruise liners and, of course, planes.  So a bit of a tall order. And with such overwhelming demand, might mineral prices not increase just slightly as well? And what about the carbon dioxide generated by this mining? Volkswagen tell us that an electric Golf would spend the first 100,000 km of its life simply repaying the Carbon Dioxide debt generated in the manufacture of the car and its battery as compared to a normal Golf.  So then, if we cannot get nuclear fusion working in time, what else could we do?

Perhaps there's an alternative path? Hydrogen. We could replace natural gas in our mains with hydrogen and use it in fuel cells to create the electricity to power our vehicles. Of course this ‘solution’ is not as straightforward as it may look.  We would need to modify our boilers, although Worcester Bosch have already produced a prototype dual fuel - natural gas/hydrogen boiler. So we could carry on using our existing radiators and not have to make a mad dash to insulate our houses.  To make sufficient fuel cells though would involve using platinum as if it was going out of fashion, although it seems that other, carbon-based,  catalysts may be possible.  Simply making hydrogen though would store energy ready for immediate use. We could make hydrogen during off peak times or even import it from countries who do not need as much power as we do. So it all looks rather more sustainable.  Which is, I think, what we're all looking for.

To be continued...   

Paul Buckingham

12 February 2020

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