Running out of battery is one of the major concerns for motorists when it comes to electric cars.
However, a recent study has revealed that an EV can be driven an extra 19 miles after the battery charge is emptied and the dashboard shows zero miles of range remaining.
After conducting the research by testing 10 of the latest electric models, What Car? Stated that manufacturers are deliberately programming range readout to be conservative to give drivers ‘an emergency buffer’ before running out of battery entirely.
A total of 10 electric cars were put to the test to see how far they could travel on a fully-charged battery in summer conditions.
The study found that 8.1 per cent shy of its claimed single-charge range was the best. The worst was almost a fifth (18.6 per cent) short of their official WLTP averages.
However, in each case the figure was helped by the vehicle continuing to run for several miles after the instrumentation said there was nothing left in the battery, with car makers appearing to keep aside a few kilowatts of power to act as a fuel reserve.
While petrol and diesel cars are expected to keep going for around 25 to 45 miles when the fuel light comes on, there has always been a big fear that electric models will conk-out immediately when the range readout hits the dreaded 0 per cent.
What Car?’s tests have found that it’s not the case.
Of the cars assessed, the £54,980 BMW i4 eDrive40 M Sport not only travelled the furthest distance on a charge but also had the biggest emergency buffer.
It can travel a total of 316 miles (29 miles short of the official 345-mile claim), and 19 of those miles were completed with the digital readout saying there was zero range remaining, the tests revealed.
Offering up to 17 miles of additional range, Kia’s Niro EV (£41,745) and Volvo’s XC40 Recharge (£51,750) tie in this department, while Tesla’s ‘Long Range’ variants of the hugely popular Model 3 and Model Y have zero-range reserves of 13 and 11 miles respectively.
Starting from £54,640, Volkswagen’s new ID.5 SUV Pro Performance has 15 miles of driving distance left when the readout says it should be empty of charge. This was more than the £29,495 MG ZS and £47,195 Kia EV6 GT (both 13 miles), as well as the £38,390 Cupra Born (10 miles).
Even though a BMW topped the table, another model from the Bavarian brand didn’t do so well. The £65,865 iX3 M Sport Pro SUV had the smallest range reserve, measured at just 5 miles.
What Car? Editor, Steve Huntingford, said: “The fear of what will happen if you run out of charge in an electric car continues to put many people off making the switch, but our test showed that you not only get plenty of warning, but that even when the range readout hits zero, you’ve still got plenty of time to make it to a refuge area or find somewhere else safe to stop.”
The award for shortest summer range of the 10 cars tested went to Cupra’s Born hatchback (which is a rebrand of the Volkswagen ID.3) with a measured 219 miles compared to a claim of 249 miles.
The second most-bought new car in 2021 and one of the best-selling electric cars in Britain so far this year – Tesla Model 3 – has the biggest range shortfall compared to claims.
The Model 3 fell furthest from its claimed range, measured by What Car? as being able to cover 293 miles on a single charge compared to an ‘official’ figure of 350 miles – a 57-mile – or 18.6 per cent – range deficit.
Three of the cars tested during the summer months have also been put through their paces by What Car? in its most recent winter range test – providing a direct comparison of efficiency based on the seasonal temperatures.
The Kia EV6 RWD GT-Line an extra 50 miles in the summer, the BMW iX3 M Sport Pro covered an extra 41 miles and the Tesla Model Y Long Range a further 57 miles.
The trio went 49 miles (21.4 per cent), on average, farther in the summer range test, when the air temperature ranged from 24 to 29 degrees Celsius, than in winter, when it was 3 to 7 degrees.
Previous research by What Car? found electric cars equipped with a heat pump lose less range when temperatures drop, with the heat pump drawing excess heat from the electric drivetrain and distributing it around the interior of the car through the air conditioning, reducing the strain on the battery.
On a 15-mile route consisting of 2.6 miles of simulated stop-start urban traffic, the tests were conducted on a closed proving ground with four miles of steady 50mph driving and eight miles driving at a constant speed of 70mph, to simulate motorway journeys.
Each of the 10 cars was fully charged and left outside for 15 hours, before being plugged in again to check the batteries were still at 100% for the start of the test.
They then had their climate control systems set to 21 degrees and were driven until they ran flat, with driver swaps at the end of each circuit, and the cars’ positions also changed to ensure no car was constantly punching a hole in the air to improve aerodynamic efficiency for the others.