Battery cars on Britain’s roads are lasting as long as petrol and diesel cars, according to a study that has found a rapid improvement in electric vehicle reliability.
An international team of researchers has estimated that an electric car will have a lifespan of 18.4 years, compared with 18.7 years for petrol cars and 16.8 years for diesels, according to a peer-reviewed study published on Friday in the journal Nature Energy. The findings were based on 300m records from compulsory annual MOT tests of roadworthiness.
Automotive engineers have long suspected electric cars will be more reliable than petrol or diesel cars, because they contain many fewer moving parts. Data has been limited, however, because the earliest mass-market electric cars are only just reaching the end of their lives.
The researchers, from the University of Birmingham, the London School of Economics, the University of California San Diego, and the University of Bern, Switzerland, used MOT data to estimate the failure rate of all cars – ignoring scrappage in the first few years, which is most likely to be related to accidents.
The analysis found that Tesla cars had the longest lifespan among battery cars.
They also found that all new cars increased in reliability over the years, as technology improved. The improvements were most marked in electric cars. The researchers said this was a result of carmakers rapidly learning from their early mistakes in battery models: it is harder to find improvements for petrol and diesel technology, which has been around for many more years.
A longer lifespan would add to the environmental benefits of an electric car v a petrol equivalent, because the addition of new wind turbines and solar power to the grid will make the electricity they use cleaner every year. Carbon dioxide emissions from use will eventually drop to zero if renewable energy is used.
The findings could also help to address concerns over expensive repairs that have pushed up insurance costs for some electric cars.
Robert Elliott, a professor of economics at the University of Birmingham and one of the study’s authors, said: “BEVs [battery electric vehicles] offer significant environmental benefits, especially as Europe switches to a more renewable energy mix. Despite higher initial emissions from production, a long-lasting electric vehicle can quickly offset its carbon footprint, contributing to the fight against climate change – making them a more sustainable long-term option.”
Electric cars on average were also driven 124,000 miles over their lifetime, more intensively than petrol, although less than diesels, which have been favoured by people who regularly cover longer distances because of fuel cost savings.
The number of electric cars sold in the UK is rising rapidly before a ban on sales of internal combustion engines in 2035; while China and Norway are leading the transition globally.
