Q: We currently own a hybrid which we bought second-hand. We would like an EV but I’m concerned about the ethical sourcing of raw materials and the human rights impact. For us, keeping our current car is a more sustainable green action than even buying a used EV. Can you please comment on the sustainable sourcing of raw materials for batteries? – Claire Reilly
A: The answer to this question is somewhat fraught with ifs and maybes, but in general the consensus among experts is that an electric vehicle (EV) is always, in the long term, going to have a lesser impact on the environment than a petrol or diesel vehicle.
The occasionally voiced assertion that a petrol or diesel car pollutes less lies in the fact that more energy is needed to make the battery of an EV than is needed to make the entirety of a combustion-engine car. That is absolutely true, and to an extent that puts electric cars in debt to the environment at the point of being rolled out of the factory. At that particular moment, an electric car has indeed “polluted more” than an equivalent combustion model.
However, it’s not that simple. For a start, the energy needed to create those batteries can be drawn from renewable sources – wind, solar, and hydro – and increasingly that is the case. Indeed, Volkswagen claims that its ID electric models roll out of the factory as “carbon neutral” thanks to the use of wind and solar power in those factories, although it does also include an element of carbon-offsetting, a method on which the jury is still very much out.
Previous research by Polestar – the electric and performance brand spun off from Volvo – indicated that a new EV would have to be driven for more than 50,000km before it overtook a petrol-engine car in terms of its total lifetime emissions.
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Again, the figure is not as black and white as it seems. It’s a moving target and depends hugely on where and how the car in question, including its battery, is made and what powers the electricity grid from which it is charged. More renewables on the grid shortens the mileage considerably; more coal, gas, and oil on the grid stretches it out.
There’s another factor to be taken into consideration, however. Even assuming that the manufacturing process for a battery does use more energy than making a traditional petrol engine, what happens next? You put petrol in and burn it to drive around. No matter how efficiently you’re doing that burning, it’s still burning, it’s still CO2 being emitted, and it’s a one-way system. You can’t recover that CO2 and start again.
By contrast, that’s exactly what you can do with electric power. Once it’s been used for a journey, the battery can be recharged – ideally with renewable energy of course – and used again. And once it has lived out its useful life as an EV battery, it can be used again.
Not only can it have a second life as static storage battery (which can be used to store renewable generated electricity for peak demand), but it can eventually be recycled, at almost a 100 per cent rate, and turned back into new batteries for the next generation of cars.
Even in the worst-case scenario, an EV is still less polluting than a conventional car. Eco-think-tank Transport & Environment has crunched the numbers, and found that: “In the worst case scenario, an electric car with a battery produced in China and driven in Poland (where most power generation is largely from coal) still emits 37 per cent less CO2 than a petrol car. And in the best case scenario, an electric car with a battery produced in Sweden and driven in Sweden [lots and lots of renewable energy on the grid] can emit 83 per cent less than petrol.”
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There is another issue to consider and that’s the environmental and human costs of mining for battery materials.
Current battery designs rely on the likes of lithium, manganese, cobalt and graphite, none of which you can just find lying around. So they have to be dug from the Earth, in intensive mining operations which have their own environmental costs.
Equally, rare materials such as cobalt are found in parts of the world – the Democratic Republic of Congo especially – where mining has been linked with appalling human rights and child labour abuses. Car and battery manufacturers say that they are going to significant lengths to ensure that their supply of such materials comes only from legitimate operators, but there remains a significant question mark over the sourcing of battery materials.