We tested them in cold weather earlier this year, and now the heat is on to find out how close electric cars can get to their official ranges in near-ideal summer conditions
Will Nightingale Will.Nightingale@haymarket.com
TWICE A YEAR (in the height of summer and the depths of winter), we put 10 electric cars through a ‘drive ’em till they die’ test to see how realistic their official (WLTP) ranges – the figures you see in the brochures – really are.
We’ve never found a car capable of matching (let alone beating) its official range, but the weather this year was warmer than for any previous test, so will one of our contenders finally prove it’s possible?
Some of the cars lining up, including the BMW iX3, Kia EV6 and both of the Teslas, have taken part in previous tests, but there are plenty of newcomers, too, including the BMW i4, Kia Niro EV and Volkswagen ID 5.
HOW WE DID IT
For obvious reasons, it wouldn’t be safe to deliberately run the cars out of charge on the public road, so we always use our test track in Bedfordshire. We followed a relatively simple test route of around 15 miles, which included 2.6 miles of simulated stop-start urban driving, four miles at a steady 50mph and eight miles at a constant 70mph. The rationale for the high percentage of high-speed cruising is that drivers who want to travel long distances in one hit are likely to be using the motorway network.
The cars were fully charged and then left out in the open overnight – for roughly 14 hours in 21-30deg C ambient conditions. The following morning, all 10 were plugged in again to check they were fully charged before the climate control was set to 21deg and the headlights switched to auto.
Normal (or the closest equivalent) driving mode was selected (no Eco modes were allowed) and the cars were left in their default regenerative braking setting – if an ‘automatic’ or ‘adaptive’ mode was available, this was selected.
The cars were then driven repeatedly around our test route in convoy, with driver changes and a switch in running order at the end of each lap. It was a relatively hot but cloudy day and the air temperature ranged from 24-29deg C during testing. The warm temperatures meant the air conditioning systems were running continuously to cool the cars’ interiors.
THE WINNERS AND LOSERS
Unsurprisingly, the car with the smallest battery – the Cupra Born – ground to a halt first. It still managed a respectable 219 miles, thou
