Allied to the question: How does cold weather affect electric vehicles?

How does hot weather affect electric vehicles, particularly when the atmospheric temperature is above 30 C and closer to 40 C, as can be experienced in tropical or desert climates during summer?

Within the category of performance I'm also interested the performance and efficiency of critical components such as the battery/batteries.

  • Not much if there is no air conditioner. Dec 5 '19 at 15:45
  • It's all good news if there is no air conditioner. I love a hot Wyoming night; I get a very notable MPG boost in my gas car cruising at posted limits. Dec 16 '19 at 2:08

It takes less energy to cool a passenger compartment from 90 degrees F to 70 degrees F than it does to heat a passenger compartment from 25 degrees F to 70 degrees F:


And hydrogen-fuel-cell buses are claiming the biggest advantage over battery-powered buses in cold weather:


  • And it gets better still if the heating is resistive, because air conditioning is always heat-pump based. Also, air conditioning is not necessary. I haven't had an A/C car since 1998. Dec 16 '19 at 1:58

Hotter air is less dense. If you turn off the AC, you should be getting increased range.

However, most people value comfort over range, and thus, the increased range won't materialize but rather the range decreases due to more AC need.

Also, if you don't do anything to the tires, hotter air increases tire pressures, reducing rolling resistance.

  • The air density has a negligible effect, the difference between a car full of warm air and a car full of cold air is about 1 lb. Dec 6 '19 at 11:33
  • @ChristopherGilmour Disagreed. It affects air resistance by 25%, see my comment to sustainability.stackexchange.com/a/9729/6393
    – juhist
    Dec 6 '19 at 11:46
  • Do you have any references that back-up your claim about 25% more air resistance?
    – THelper
    Dec 6 '19 at 16:54
  • @ChristopherGilmour you're wrong. Google "hot-and-high" which is an aviation term, and understand why it has such a profound effect on aviation. What makes it hard for airplanes to fly gives my gas car better MPG. It's not the air in your car. It's the air you're pushing out of your way. Thelper look at aviation performance charts. Dec 16 '19 at 2:03

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.