With an internal combustion engine, excess heat from the engine is used to keep the passengers warm in the winter months. Hybrid vehicles also have ICE engines. But how will EVs heat the passenger compartment in the winter? As we all know, electric heaters are VERY energy consuming. I supposed if your battery was good for 60 miles, and you only drove 35 miles per day, you could probably use an electric heater. Any comments, suggestions, or ideas?
Electrical heaters are no more energy consuming than gasoline heaters. Why do you think Prius mileage takes such a hit in the winter. You are not really heating with waste heat. Many older cars produce massive amounts of waste heat, but an efficient car like a Prius tries to keep the energy for propulsion, so waste heat is minimal. To answer your question, most EVs use electrical resistance heaters. It's the only sensible solution. You wouldn't expect them to carry fuel just for heating, nor would it make sense from an energy standpoint. I suppose a heat pump could work, but the size and weight would be an issue. Tom
Good point, and one I'll have to consider as I will look at electric vehicles in the next few years. Here in Ottawa area we have to deal with winter temps as low as -35 or so, lower with windchill. Perhaps EVs will be rarer here until manufacturers work this out. Yes, electric heat will work but will be an impediment to range. Would be nice if ANY heat loss from motors could be recycled into cabin. Other ideas: - Heated garage. - Black car and sun exposure for outdoor parking. - Plugin block-heater like device for cabin. (Might as well re-charge it too, especially on plugs you aren't paying electric for. - Warm coats. - Hot water bottles or pocket warmers or electric socks. - Hardy attitude and a cup of joe at the drive-thru.
Gasoline cars are probably 10% efficient overall. They have a theoretical maximum efficiency of around 37%, but seldom achieve that since 95% of the time they are operating well outside their ideal parameters of rpm and power output. Therefore, 90% of the energy contained in the gasoline is dumped as waste heat (yes, even the Prius dumps a lot of waste heat: the reason it does worse in winter is because it wants to keep itself hot, in order to limit emissions, and the cold weather sucks heat out faster than warm weather does). Since the car is dumping 90% of the fuel's energy as waste heat, there's plenty of free heat for the cabin. (It's not really free, because you're paying close to $4/gal for the gas; but you've already paid for it, and it's going to waste anyway, so it costs nothing more to heat the cabin with it.) An electric motor is close to 100% efficient (nothing is 100% efficient, but an electric motor is close) so there's too little wasted energy to salvage to heat the car. I had an after-market heater installed in my Xebra because Zap provides a very weak one. It draws less than 1/4 as much current, on high power, as the motor does when cruising at a steady 35 mph. (The motor draws considerably more while accelerating.) But it puts out so much heat that after a couple of minutes I have to shut it off, and then I run it on low (1/8 what the motor draws while cruising) about one minute every 2 or 3. Thus on a cold day if I run the heater to keep warm, my range maybe drops from 40 miles to 35. Not such a heavy price to pay. Enjoy wasting 90% of your fuel's energy while you can! Pretty soon gas will be so expensive that heat will be a fond memory.
It's always good to hear from someone that has experienced this before. Thank you. The rest of you have good ideas also. Hiremichaelreid, good thinking to plug in the heater to a wall socket while you are still in your garage and get a head start on heating the interior/cabin.
