Gavin Green: carbon footprint complexity
This autumn, climate experts and campaigners will gather in Glasgow for the UN Climate Change Conference. David Attenborough will talk authoritatively, Greta Thunberg will preach angrily, Boris Johnson will promise loftily and Extinction Rebellion will protest loudly. No doubt the great and the good will virtue-signal in electric cars, which they’ll use after alighting from their private jets. One such VIP EV passenger will be Allegra Stratton, the UK government’s climate spokesperson. May I suggest she uses her private car – ‘a third-hand Volkswagen Golf ’ – instead? It may be the greener choice.
As I write, Stratton is getting into mischief from an unlikely alliance of the press, environmentalists, politicians and even the AA for refusing to buy electric. She’s sticking with her old Golf. Her ‘excuse’ is that she uses it to visit relatives in Scotland, the Lakes, North Wales and Gloucestershire, from her home in London. An EV, she says, would be less convenient.
As anyone who drives an electric car regularly knows, a petrol or diesel car is certainly more convenient on long drives than an EV. It has a longer range and can be refuelled in a few minutes, not 40. There’s also plenty of evidence that old, economical, well-maintained cars are surprisingly green.
Britain’s foremost expert on carbon footprints must surely be Mike Berners-Lee, brother of web founder Tim, and author of the scholarly How Bad Are Bananas? The Carbon Footprint of Everything. It investigates the real impact on our planet of just about everything from text messages to surfing the internet, from eating bananas to buying cars. The revised 2020 edition also deals with recent trends, from Zoom calls to electric cars.
Should we all be rushing to buy electric cars? No, says Berners-Lee. Keep your old car for as long as it’s reliable and look after it. The exceptions are for high-mileage drivers or for gas guzzlers, such as big SUVs.
The reason is simple. Buying a new car comes with a heavy carbon footprint. Its manufacture emits much more carbon than is generally acknowledged. EVs are worse than petrol cars.
Working out the total carbon manufacturing emissions of a car is complex. What’s certain is that studies rarely take into account all the factors, including ores mined and metals extracted; steel, rubber and glass manufacture; transport of materials and vehicles; making the tools to build the cars; plus o ce heating and associated business travel.
To reduce manufacturing emissions, hang on to your old car and maintain it well. When you need to buy a ‘new’ car, buy a ‘secondhand, light, simple and fuel-e cient model’, says Berners-Lee. If buying new, get a small light electric car. Berners-Lee, incidentally, drives a Peugeot 107.
An EV’s manufacturing carbon footprint is higher than a petrol car’s because batteries take a lot of energy to make. Those new EVs parading around Glasgow will have a higher carbon footprint than a new petrol car.
According to Polestar, building a Polestar 2 produces 24 tonnes of CO2. A similar size petrol-powered Volvo XC40 emits 14 tonnes. (Berners-Lee estimates his 107 has four tonnes of ‘embodied’ CO2-equivalent emissions compared with an electric Renault Zoe’s 11.)
Conversely, EVs produce less carbon ‘in use’. Over a car’s lifetime, an EV is cleaner, as Berners-Lee and Polestar point out. By how much depends mostly on the electricity that powers them. Either way, you need to do a lot of miles to offset the bigger manufacturing footprint.
Using the average electricity mix in Europe, Polestar calculates you’d have to travel 48,500 miles before a Polestar 2’s total carbon footprint falls below a Volvo XC40’s. Globally, where average power generation is dirtier, it rises to 69,500 miles. It falls to 31,000 miles if wind power only is used. Luxury EVs could need six to nine years’ use to break even.
So, instead of parading heavy new carbon-intensive EVs at Glasgow, I suggest a fleet of well-maintained, fuel-frugal lightweight Peugeot 107s, as owned by me and Berners-Lee. That would be quite a statement.