Electric vehicles are a strangely contested technology. In some circles they are celebrated, many are supportive but hesistant, and some downright hate them. What I find interesting about the hatred is that it comes from completely opposing directions. Men who like their cars to go ‘vroom vroom’ hate them, with Jeremy Clarkson the iconic leader of that miserable band. But lots of environmentalists hate them too.
I constantly hear objections to electric cars from committed greens. In some circles you can’t mention them without adding a collection of caveats, because if you don’t, your audience will inevitably raise them for you. This reached an extreme recently when I saw a well-meaning tweet celebrating the cutting of the government grant for electric vehicles. They shouldn’t be any support for them at all, she argued, because “EVs are ecocidal.”
Scepticism from greens is really unhelpful, because net zero targets simply will not be reached without electric vehicles. They don’t solve everything. They’re not ‘the’ solution to sustainable transport. But they are an absolutely vital piece of the jigsaw, and so we really need to have a more grown up conversation about their role.
Prompted by this bizarre tweet, I thought I’d write a post or two in defence of EVs. You don’t need my caveats again – see this post on the ‘three R’s’ of travel, or the hierarchy of sustainable transport for where cars come in the list of priorities. Let’s look at some specific objections, starting today with roadside air pollution. That’s the pollution from traffic, rather than pollution from power stations to charge your electric cars, which I’ll deal with another time.
Let me give a specific example, in the form of Chris Woodford’s mostly excellent book on air pollution, Breathless. While castigating diesel fumes, he then adds this: “though electric cars sound marvellous… there are still emissions from brakes, tyres and road dust to worry about.”
Or here’s George Monbiot, writing about electric cars last year. “A switch to electric cars will reduce pollution. It won’t eliminate it, as a high proportion of the microscopic particles thrown into the air by cars, which are highly damaging to our health, arise from tyres grating on the surface of the road.”
This is a line I’ve heard many times now – electric cars produce pollution from their brakes and tyres. This is particulate pollution, the small particles that are especially harmful to health. But petrol and diesel cars also have brakes and tyres. Nobody talked about this until electric cars came along, and it is only ever mentioned with reference to electric cars. Apparently electric cars are seriously polluting after all, argue the tabloids gleefully. You might even get the impression that they’re not worth bothering with at all. “It’s hotly debated whether electric cars will end up spraying more particulates into the air than petrol and diesel ones” says Woodford.
What neither Woodford nor Monbiot do is say what percentage of overall traffic pollution comes from these dreaded tyres and brake pads.
So let’s take a look. The government ran a consultation on this very question in 2019. They found that ‘non exhaust’ emissions from traffic are around 8%.
I have a lot of respect for George Monbiot, but I’d want to challenge him over the question of whether 8% counts as a “high proportion”. Exhaust fumes are overwhelmingly the big issue. There is no question whatsoever that if we want to improve air quality, it’s diesels and then petrol cars that we should focus on first.
Non-exhaust pollution isn’t negligible, which is why the government are investigating it. It’s also under-studied and it isn’t consistently measured, because not enough people had thought to measure non-exhaust emissions until the question of EVs came up.
It’s also highly contextual, and that 8% cannot be applied across every road in the UK, let alone the world. A study in Spain found that half of air pollution is from exhausts and half from other things – mainly dust. So if you live in a dusty place, EVs will make less difference – though that’s still a halving of air pollution.
How do you reduce non-exhaust pollution? The weight of vehicles matters, and Heavy Goods Vehicles are the worst culprits. Smaller and more lightweight vehicles will cause less wear and tear on roads and rubber. Another factor is driving style, which accounts for a third of tyre wear. Eco-driving techniques would help, and I reckon electric car drivers would already be more likely to use them. Electric cars usually have regenerative braking, which also reduces brake pad wear. And of course, the biggest difference will come from reducing the amount of journeys and the number of cars on the roads in the first place.
This is, ultimately, why many people raise this issue about electric cars and pollution. They want to emphasise that the best solutions lie in active transport or public transport, not in perpetuating car culture with EVs. I agree 100%, but let’s make that point by presenting the case for those solutions, not exaggerating the flaws of electric vehicles.