“How far can you go on a charge?”
Every time a rider asks that question I pause and think. “How can I explain this easily?” Riders may think they’re taking a test ride in a Tesla but really I’m testing my ability to explain what electric car ownership in the mountains really means.
Here’s the deal, there are summer miles and there are winter miles. Winter miles are harder on the batteries- by a long shot.
Here’s a pic I took of the dash yesterday afternoon. The battery is showing 211 miles left in the charge. In summer this would be true. In fact in summer I could probably get a bit more mileage out of that charge.
But there is another graph to watch which predicts how much range you have at your current energy usage. This is the real mileage estimate given the last 30 miles of driving. This is what the “watts per mile” gauge with projected range on the touch screen says at the same time the battery is reading 211 miles:
That’s 117 miles vs 211 miles.
Big difference.
So, what are the factors which contribute to this? First off, batteries hate cold. Even when I’m storing the Tesla overnight in the studio plugged in the cold still sucks life out of the battery.
There is less regenerative charging when the batteries are cold. There is a lot of up and down in the mountains and during summer I can use that to my advantage. Every time I go downhill I put juice into the batteries… but not so much in winter. Tesla has a safety feature when the batteries are cold which limits regenerative braking.
Friction. Snow tires are soft, winter roads are bumpy, the wheel wells fill up with snow easily and need to be power washed. All of these factors add friction which reduces efficiency.
If the batteries are cold, so am I. Yes, I’m running the heat in the car. Tesla will remind you that it uses less energy to warm your seat than your entire car but that does not keep the frost off the windows. Running the “climate” control on high and turning the fan down is the only way I’ve found to keep the windscreen clear.
“How far can you go on a charge?”
“Well, that depends, on summer miles or winter miles…”