Make no mistake: electric cars are less efficient in the winter. The cold weather affects battery performance, reducing range and forcing you to charge more often. But with EVs accounting for 14.5 per cent of new car registrations, what sort of mileage might go missing? And can you still drive an EV in sub-zero temperatures?
The short answer to the second question, of course, is yes. For years (thanks to strong incentives) Norway’s electric-car uptake far surpassed that of any other global market – in spite of its extreme winters. The UK, in contrast, has a relatively mild climate, so driving an EV year-round over here should be a piece of cake.
If the temperature were to drop to just five degrees and you ran around everywhere with the heater on, that figure could topple to 187 miles according to Renault’s sums – a 20 per cent reduction in range. It’s worse still when things fall below freezing; at minus five degrees a Zoe R135 will return just 152 miles before needing to be plugged in. It’s important to note that the bigger the battery, the greater potential for energy loss.
Why does cold weather reduce EV efficiency?
Cold temperatures adversely affect EV batteries because they rely on chemical reactions to store and release electricity. Lithium-ion batteries – the most common cells used in electric and hybrid cars – work when lithium ions move from the anode to the cathode; cold slows this process down and restricts battery performance. The result can be a dramatic loss in usable range.
Yet for many drivers, even 152 miles will be plenty. If you’ve got a short commute and can charge up at work or at home, you could even take advantage of pre-conditioning – heating your car’s cabin, defrosting the windows and switching on the heated seats – before you leave in the morning.
Do low temperatures impact charging speeds?
While there are no added dangers when charging your car in rain or snow, another adverse effect of the cold is that charging speeds from public rapid chargers may be slower. Tesla admits that extreme weather can result in reduced charging speeds at its Supercharger stations, and the same is likely to be true of other networks.
Are some electric cars better than others in the cold?
Not all electric cars are the same and our non-scientific testing of various different EV models has revealed quite the disparity in the way range is effected by the cold. At one end of the scale, the Hyundai Ioniq Electric continued to return efficiency of over 4 miles per kWh in mixed driving even when the average ambient temperature fell close to zero.