Electric car owners in cold regions certainly have good access to electricity where they park. But what happens if you are visiting and have to leave the electric car overnight in the freezing cold without access to electricity?
Looking for the cold
It was reported -16 degrees, but already after Lillehammer I saw that the degrees crept down to -18. It looked promising for a cold test. In Gudbrandsdalen, temperatures can vary with local conditions. I was on my way to check the holiday home before the winter holidays. Thawing water pipes, turning on the heat, shoveling, putting up firewood, chasing away mice, as well as other necessary caretaker tasks. It takes time to fire up a house with an inside temperature of 4 degrees. The cold did not disappoint. During the evening and night, the outside temperature dropped to -24,9 degrees.
The cold steals kilowatt-hours
I parked the Tesla with 80% on the batteries after charging on Øyer. The remaining battery capacity decreased in line with the falling outside temperature, but stabilized at 73% when the thermometer stopped at -24 degrees. During the night, 7% of the batteries had evaporated in the cold - of Tesla's 75 kwh, this amounts to 5,25 kwh.
Lightning-fast heating of the compartment
Ready to leave, I started heating the cabin by preheating the batteries at the same time as scraping the windows. Scraping wasn't really necessary. The car warmed up long before I expected - much faster than in modern petrol cars. After I had turned off the water in the laundry cellar, loaded the luggage into the car and locked the house, the car was wonderfully warm and ice-free. Almost 15 minutes had passed.
Just driving?
The heating had taken another 2% of the batteries. They were now down to 71%. In total, the night had cost 9% of the battery capacity (6,75 kwh). But I was a little too quick on my feet to get off. The app that heats up the car shows a battery symbol with an ice rose when it preheats the batteries. It switches off when the temperature in the batteries is 19 degrees. I preheated for 15 minutes. Ideally, I should have continued preheating until the battery symbol went out. Preheating the batteries is not only for comfort, but to make the best use of the remaining battery capacity. If the batteries are too cold, they will not accept charging from regenerative energy. It therefore pays to preheat the batteries even if the car is not plugged in. I could have preheated for maybe 30-60 minutes. All monners leave. 15-20 minutes drains maybe 2 percent of the batteries, but makes the batteries give more range when you start driving.
Preheating the batteries
The pre-heating in the Tesla 3 uses the electric motors to produce the heat. The heating of the batteries is water-based – coolant that passes through all the cells. The pre-heating does not drain more power from the batteries than quiet driving, so you can start the pre-heating in good time. When you come from petrol and diesel cars, you are set on getting off as soon as the routes are ice-free. But preheating electric cars does not generate any toxic gases or noise. You can optionally start pre-heating without the air conditioning - or low temperature in the passenger compartment and gradually turn up the heat to save the batteries.
Slow charging in the cold
Although the batteries had not reached ideal temperature, they worked fine from the first kilometer. Consumption was the same as the day before. After 1 mile of driving, I set my destination to a charging station to buy coffee and sausage - and test charging. Tesla preheats the batteries before arrival, which in my case was calculated for 10 minutes. The batteries thus received additional preheating to cope with the cold. But the batteries were probably not quite ready to receive electricity. It took a few minutes before charging started, and then with low power. Although I was the only customer at Tesla's Supercharger facility, the maximum charging power did not reach more than 27 Kw during my little lunch break. The day before, the batteries received 87 Kw. But I didn't really need much power, so when the break was over, I moved on.
No big increase in consumption
The experts warn against higher electricity consumption in the cold - up to 41% higher than in summer. My winter consumption on the section Oslo - Øyer this trip was 25% higher than the lowest record measurement from September last year - and about the same level as other measurements made in warmer temperatures under alternating driving and driving conditions. Nor did the trip up offer any surprises in terms of range. I don't know if it is of great importance, but I drive with a thick sweater and an indoor temperature between 19-20 degrees. It is possible T-shirt and 25 degrees could have given other experiences.
Don't forget to preheat the batteries in the cold!
Tesla Owners Club Norway: Battery heating
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