We have a Bolt and a Model 3P, and the HVAC effects are interesting. I think GM does a great job with the software and management of the EV, and are very open with how things work. For example, if it is cold out the Bolt will adjust its projected range based on the temperature. And, it will also show you the impact of the HVAC (heat mainly 1.5kW-2kW draw on the resistive heater unit, it is fast!). If the car shows a range of say 260 miles and you turn on the heat, that range estimate will drop down by 20 miles or so and you'll see that happen on the gauge. Turn it off, it'll go back up. IT might not be perfectly accurate, but it isn't a bad strategy and I appreciate the honesty.
Tesla does none of that. Charge the car in cold weather and it'll show the same max mileage in warm weather. Heat on or off (Tesla has a heat pump so more efficient but people do complain about them in Canada and other cold places) the range it projects is always the max EPA rated range. That sucks, because as you drive the range will drastically decrease but you really don't notice it that much. Poor strategy. Now, if you trip plan with the map it will account for cold weather impacts on range and so on, which is a nice feature and accurate. But one shouldn't have to use the navigator to get a realistic range estimate.
As I've always said the Bolt underpromises and overdelivers, while the Tesla over promises and under deliveries. At least, that is what Julie and I feel our seven years of driving both the cars together have taught us. We've even done fun experiments where we drive both cars, fully charged, same day and same time down to the beach house to observe these behaviors. We've proven that the real world range of the Bolt is the same as the Tesla, despite the difference in EPA ratings and advertised ratings.
Chevy Bolt resistive heater unit
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