Baby it’s cold out there… It’s late November in the UK and the heating has gone on in homes across the country as temperatures start to fall. It's no secret that electric vehicles experience a lower driving range in extreme temperatures - both cold and hot.
Before you get overly concerned about your winter range, let’s just drop in one of the EV features that you will definitely enjoy this winter - prewarming on your driveway means you won’t be doing early morning windscreen scraping for a start!
What happens to EV range in winter?
For most of the year, EV drivers can expect to exceed their car’s miles per kWh rating, but on cold days, you can expect fewer miles from your car between charges.
The EV's battery is more efficient at when it is warm (this is roughly a 12% reduction in range in the cold), but the biggest drain on the car's battery by far comes from heating the car for passenger comfort.
You might never have noticed, but efficiency of a petrol car drops too, by as much as 22% over very short trips in cold weather. Yet, lower efficiency and lower range becomes much more obvious to an electric car driver.
Top tips for EV driving in winter
If this is your first year driving an EV, there are many actions that you can take to maximize your comfort and range when the temperatures dip. Here are our top tips:
Top of the list is getting to grips with the pre-warm function. Just about every new EV sold today offers some sort of prewarming or preconditioning feature. Prewarming allows you to heat the battery and cabin while you are still plugged in at home. This means you'll leave the house with a fully charged and heated battery, plus you can enjoy the first 5 minutes of your drive in a lot more comfort than when you drove a chilly petrol or diesel. The preheat means more energy in the battery can be used for its main purpose, to drive the vehicle. It also means you can leave the house without spending 5 minutes scraping off ice from the windscreen.
You can set the preconditioning to begin at a set time every day so that your electric car is ready when you leave in the morning. Make sure the car is plugged in while you precondition, because you want to draw energy from the grid to do this, not drain down your battery.
Time your charge
For maximum efficiency, try to time your overnight charge to finish around the same time as you leave in the morning instead of relying on prewarming alone. A battery warms as it charges, giving you more available range for your day than a battery that has filled and then cooled.
A warm battery also means that the regenerative braking will also work better. Good news if the roads are icy first thing, as regenerative braking is thought to be better than even ABS braking at avoiding skids and slides!
Using the regenerative braking system on your EV to maximize range is always a good idea when you are driving in cities or rural roads. (For motorway trips, the cruise modes without regen may just have the edge in terms of miles per kWh efficiency). Regenerative, one-pedal driving is one of the best things about driving an electric car.
As we mentioned, when the battery is very cold, the regenerative braking system will be less effective. Cold batteries can't accept as much surplus energy as warm batteries can. You won’t get much regenerative brake power from a completely full battery, either.
Use the Eco mode
Most EVs have an option called "eco mode" or something very similar. Every EV implements eco mode differently, but this mode generally reduces the amount of power supplied to the drive motor and energy-consuming features like the heating system.
Another benefit to using the eco mode in the winter is that by reducing the power to the motor, the car accelerates slower, and helps to reduce the possibility of wheel spin. Therefore, even if range isn't an issue, it's probably a good idea to use eco mode whenever driving when there’s ice or snow on the roads.
Eco mode reduces the car's acceleration, and helps to reduce the possibility of wheel spin on icy roads
On the same point, in many EVs, the battery essentially lowers the centre of gravity of the vehicle, which adds extra stability, makes them easy to maneuver and gives you good traction on icy roads.
The eco mode is likely to restrict your comfort too, meaning the heating will not be able to go at full pelt whilst you are driving in eco mode. This moves us on nicely to the next topic - heating an EV in winter.
Unlike a petrol or diesel, there's not the huge amount of waste heat emanating from a combustion engine, so in an EV every bit of heat you need comes from your onboard heating systems. It takes a lot of energy to heat the air in a car, so besides the motor these systems are generally the biggest energy draw an EV will have. If you are on a long journey and need to squeeze every mile out of your battery range, or if it just comes naturally to be as energy efficient as possible, you’ll want to do limit the use of the cabin heater as much as possible.
Some EVs use a heat pump system, which is more energy efficient than a resistive heater. This is definitely something we appreciate in our e-Golf, but it is an optional extra you have to choose when you buy your car. However, even sophisticated heat pump systems still can use a fair amount of energy, and will still cut into the available range.
If you haven’t got inbuilt heated seats, you can buy a set that plug into the cigarette lighter for as little as £20 - well worth the investment. Using heated seats, or even a heated steering wheel, will definitely help you cut down on the cabin heater and save energy while staying comfortable.
Dressing a little warmer, and using heated seats and steering wheel will have a very positive effect on your range and on your kWh consumption per mile.
On runs of 'dad's taxi', you won't feel antisocial by turning on an ICE engine to keep warm.
Last, but definitely not least, there is one major advantage of any EV that serves as mum or dad’s taxi. You’ll no longer have to decide between waiting around in a cold car or feeling antisocial by turning on your old ICE engine to keep warm. With an EV, the heating can go on without belching out fumes in a busy leisure centre car park (or anywhere else).
Check your tyres
This might be the most overlooked way to increase your EV's range, in both summer and in the winter. When the temperature has fallen from 10 degrees Celsius to zero, you can expect tyre pressure to drop by approximately 2 psi ( the total psi is around 32). This squashed tyre creates more road friction and will reduce your vehicle's efficiency.
Many models do have sensors that will alert you if your pressures are on the low side. As the temperature drops, the air in your tyres contracts causing the pressure to fall. Always make sure to check the recommended and maximum pressure for your tyres. It’s often written on a plate on the frame around the driver’s door.
Check your tariff
Our homes and cars start to use more energy as the nights turn long and temperatures dip low. No wonder that November is the peak time for people to look for new deals on their home energy. With an EV you might add around £30/month to your electricity bill, even if you drive only around 8,000 miles per year.
The good news is that there are lots of tariffs on the market that offer much cheaper overnight rates for EV drivers. Try our free online tariff comparison to find out which tariff works best for your car and home.Check out your savings from smart, time of use electricity tariffs
So, how much range will I lose when it's cold?
The answer depends. How much range you lose in the cold depends on: the car you drive, how you drive it, how you heat it, how cold it is outside, where you park when you're out, and many other factors. As more and more longer range EVs come on the market now, and any observed winter range loss becomes much less critical for the journeys you make.
Winter in an EV can be a breeze
But, by taking some simple steps, winter with your EV can be a piece of cake, enjoyable even. Remember that your speed increases drag and drag reduces mileage, so if ever there was a time not to speed, it’s through the winter.
Drive for 1p/mile and save up to 15 tonnes more CO2?
When you drive an EV, switching your home electricity to a 'time of use' tariff can save you up to £300/year, and lower your carbon footprint dramatically. Not sure where to start? Our free online comparison shows you the best smart tariffs for your car and home.Check out your savings from smart, time of use electricity tariffs