EV (100% Electric) Car Heat And Defrost?

Electric cars are in their infancy right now. I could be interested in one when they become larger, range increases, prices come down a little, etcetera. I’m sure that will happen.

I keep asking “How do they heat and defrost for people who live where winters are very long and cold, like I do ?”

I got an answer on Sunday. I was at (one of ?) the largest new vehicle outdoor auto show in the country (world?). I talked to the guys at the Th!nk City EV car display and looked over this little car.

It utilizes one electric motor and has a cooling system complete with liquid coolant just like a gas engine car. These cars are used successfully in Denmark.

A Th!nk City car is too little for me and it was pointed out that it is for city folks, not me. However, I am impressed with the progress and innovation and the cost and range were reasonable.

Now, how do they get heat and defrost in the EVs that mount a motor at each wheel? I think that will be the standard in years ahead.


I Forgot The Link To Pictures And Information On The Th!nk City.

I agree with your assessment that a motor on each wheel may be the ultimate EV approach. The heating, cooling I feel have yet to be resolved in a way that would satisfy the American consumer. The cheap approach is the old VW, gas heater…what a step backwards. There is some interesting work done on the the radiant to convection heating conversion which may work in the small space of a car. Don’t forget air conditioning too. This fat A… driver loves climate control too.

The cooling system is for the battery pack only. Since batteries lose potency at high temperatures, the battery pack in the electric car needs to be kept below a set temperature in order to keep them from being damaged. If you relied on a the battery’s cooling system for heat on a cold day, you’d remain cold as they don’t produce near enough heat to keep the interior of the car warm. Heating and A/C are still a big problem with pure electric vehicles on an internal combustion engine, so much excess head is produced that utilizing it to heat the cabin is incredibly easy and simple. In an electric vehicle there’s not much in the way of a heat by-product so an electric heater must be used, this uses a considerable amount of electricity.

I Have To Add A/C To My Question.

Ah…the downside of efficiency. Not enough wasted energy (heat) to keep the cabin cozy!

For most environments these vehicles would be operated in, and the distances involved, a simple CNG heating system would be virtually non-polluting, and consume a pittance of energy in comparison to motive force.

The problem being, with the demographic buying e-cars, burning ANYTHING (no matter how cleanly) is a impossibility. Better to use electricity to generate heat, even if involves consuming far more energy…

(Now that I think of it, I wonder if a dedicated fuel-burning heater in GAS cars would save energy, just by obviating the inclination to idle for a half-hour in cold weather!)

Oh, No!

The kids running the display didn’t know much. When they couldn’t help me and I saw the cooling system and motor under the hood, I assumed. You know what happens when one assumes. Darn.


The dirty little secret of GM’s EV-1 failure was the 20-30 mile range when people turned the A/C on, which they did most of the time…An effective heater/defroster would use more power than the drive motor…And what about my heated seats?

The Chevy Volt addresses and overcomes these issues. Jazzed up golf carts never can…

I think one sensible way is a heat pump system. Basically an A/C compressor driven by an electric motor, plus two solenoid valves so the condenser and evaporator can swap roles.
Heat pumps are more efficient than resistive electric heaters.

I don’t see motor at each wheel happening. More unsprung weight requires to stiffer suspension to control wheel motion, which requires a stiffer, heavier body to cope with the stiffer suspension. And a heavier body reduces range.

I’d like to see Stirling heat pumps in electric cars in the future.

I Guess I’ll Have To Wait A While Before I Can Jump Into A Large “EV” On One Of Our 20 Below Zero Mornings, But It’s OK That They’re Tinkering With Them.
They need to start somewhere.

Picture a cold, icy day in rush hour. Traffic is at a standstill because of a wreck up ahead. You have your defroster, windshield wipers, radio, & headlights going at full blast. How rapidly is your electric supply being depleted? Once taffic is flowing again, will you have enough current to teach your office?

Typo-- meant to say “…reach your office?”

Even If You Do, How Do You Get Past The Snarl-Up Caused By The Eleven Cars Ahead Of You That Ran Out Of Heat, Defrost And Sparks?

I think the ‘heat pump’ idea makes a lot of sense, those batteries would be quickly drained if resistance heating was used. I see a bigger problem in my area - I’ve been following the Mini EV on some tests, and it turns out the batteries can’t handle hot weather, temps over about 100F. That thing’s DOA in Texas and much of the south. Phoenix? Not a chance!

Sounds Like Goldilocks And The 3 Bears. EVs Aren’t Practical In The North (Too Cold) Or In The South (Too Hot), But Somewhere In The Middle, They’re Just Right.

Like I say, they have to start somewhere. These challenges will be met, I’m sure. I like the simplicity of EV’s compared with piston powered cars. Then the next problem will be with obtaining enough electricity when they start flourishing.