Is it more environmentally friendly to keep my 23-year-old petrol car or to scrap it and buy a new electric one? I drive about 8000 kilometres a year and am quite old, so my car may outlast me.
Stephen Johnson
Eugene, Oregon, US
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While the general idea of replacing an old petrol car with an electric car has environmental benefits, there are many issues that make it unlikely this is a wise decision in this particular case.
Looking first at the issue of carbon, a new electric car requires around 6 tonnes of carbon for its manufacture. During operation, an electric car produces about 94 grams less carbon per kilometre than a petrol car. So, to recover the carbon burden of the electric car鈥檚 production, the reader would need to drive their new car 65,000 kilometres, or for around eight years at their current rate of driving.
A new electric car has many other environmental issues, in particular its need for the mining of lithium, copper and cobalt. All of these elements cause serious environmental, political and physical harm at every level of their extraction and refinement.
To help the environment, the best transportation change any of us can make is to use mass transit when possible, use bicycles and electric bicycles for short trips and try to plan our car trips to include as many of our weekly errands in a single trip as possible.
Matthew Wenban-Smith
London, UK
It is most environmentally friendly to reduce the kilometres you drive, ideally to zero. But assuming that you have already minimised this, then in relation to climate change at least, you should scrap (and not sell for continued use) your old car and replace it with the most efficient electric one immediately.
The good news is that once you have got rid of your old car, your own longevity is no longer relevant, unless you are planning on being buried with your vehicle.
The basic calculation is whether the greenhouse gas emissions per kilometre for your new electric car, over its whole lifetime in use (and including the emissions associated with the extraction and processing of the materials it is made of), will be less than the current emissions per kilometre of your petrol car. For your current car, ignore historical emissions 鈥� I am afraid that is a sunk cost.
But really there鈥檚 no need to do the calculation 鈥� a new electric car is sure to have lower emissions per kilometre, on this basis, than your current petrol car.
It is the same calculation you would make to replace an old incandescent light bulb with a new LED one 鈥� you should do it immediately, and not go on heating up the planet while you wait for your old bulb to stop working.
David Gregory
Via Facebook
The for an electric vehicle is generally between 24,000 and 32,000 kilometres. Once it is past this threshold, it is then better than any petrol or diesel car, no matter what miles per gallon you are getting.
An easy way to speed up the 鈥减补测产补肠办鈥� process is to buy an electric vehicle second hand that has already covered 32,000 kilometres or more.
Terry Gillen
Tring, Hertfordshire, UK
I am in my 70s, my car is 19 years old, I also drive about 8000 kilometres a year and I want to be environmentally conscious. So, asking the same question as your reader, I have researched extensively and concluded that keeping my old car is more environmentally friendly than buying an electric one.
This is for three main reasons: first, the manufacture of electric cars has such a big carbon footprint that it can take over 60,000 kilometres of driving (less if electricity is generated from renewables) to 鈥渂reak even鈥� environmentally; second, the rare earth metals used in electric car batteries are extracted by strip mining, which has a detrimental effect on about 500 square kilometres of adjacent land; third, those mines are often in countries with dubious records on pollution and employee rights.
Consequently, I decided to keep my old car, reduce the amount of driving I do, maintain it well and follow advice for obtaining maximum miles per gallon.
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