I’m beginning to wonder a bit about pure electric cars; I’ve written before about my scepticism over the arbitrary targets governments across the developed world are setting for the death of the internal combustion engine (ICE), and now another potential speed bump is appearing before us.
Electric cars are heavier than conventional ones; obviously, because the greater weight of battery versus liquid fuel is a bigger number than the difference in weight between electric motor and engine. A greater number of horsepower will therefore be necessary to drive the vehicles at the same speed. That’s not really the heart of the problem, though. A recent report from Imperial College, London, has concluded that tyre and brake dust account for more than half the small particle pollution generated by road transport. That dust is generated by the interaction of road surface and tyre, and by the effect of applying the brakes to the vehicle. On the second of those two points, EVs quite possibly perform better than ICE vehicles, since most braking is not effected by disc/pad friction, but rather by the regenerative braking of the electric motor when the accelerator pedal is released.
But tyre dust is a function of weight, and the greater weight of EVs certainly creates more of it. In a test pitting a Tesla Model 3 against a hybrid of comparable size and performance (it was a Kia Niro, apparently, if anybody knows what that is), the Tesla lost 26% more tread than the hybrid over a distance of 460 miles driven in convoy. That matters, because those tyre particles contribute to cancer, heart problems and other medical issues.
Now, I’m not a scientist or a technologist; I can’t honestly prove anything, on either side of this. What I can do is read the summaries of the reports and point them out. What concerns me about this is the question: are we making the perfect the enemy of the good? I guess we can all agree that - regardless of any particular view of climate change/global warming - our lives would be better with less atmospheric pollution; in basic terms, the world is a better place if you can see it without a smog of industrial gasses clouding the view.
If we look at the fuels we can use to generate power, then it is quite easy to rank them in terms of the pollution they create; coal, oil, gas, nuclear, renewables. I’ve pointed out before the folly of deciding to move conclusively away from any of these before the technology to replace them adequately with something higher up the list is available. So, coal is largely gone (in the UK, at any rate; China, and indeed Germany, are not there yet), but we are not - in my view - in a position to abandon oil completely. Could it be that we should take the same progressive view of road transport? In terms of exhaust emissions, petrol and diesel are at the bottom of the pile, followed by mild hybrids, plug-in hybrids and then pure electric. But as I have written above, there are other things to add in to the overall brew. Research is being done in the production of low emission tyres, with a hope to produce major volumes annually from 2026. Also, I would suggest that it is a reasonable expectation of development that battery weight will be likely to decrease as technology improves. Perhaps until that happens to enable us to look away from the scales tipped by heavyweight battery-powered vehicles, we should focus on hybrids as a better interim solution; and then perhaps as the world rolls on, we will finally be able to sing, with The Hollies, He Ain’t Heavy………..
