"Plug-In" Electric Car Heat & Defrost


I am interested in the developing “plug-in” cars. I live about a 40 mile round trip from the nearest town, so I need probably a 50 mile+ range. That seems like not a huge problem. When everybody starts buying and plugging these cars in I am concerned with electric companies keeping up with demand, and the reduction in road tax (now part of gas prices), etc. These are not the main part of my apprehension.



Here it is… Since I live where heat and defrost in a vehicle is necessary for all or part of 8 months per year (temperatures to -25F) how is this handled in a “plug-in” car? Is it done with waste heat? Do they use gas or propane? I know electric resistance heat (like in a toaster) gobbles up electricity.



I can’t find anything when I read about the GM Volt, etc. How do they do it?



If you know, please explain it to me. Also, tell me where to read about this technology. Also, what other concerns should I be researching?

I’ve wondered about the same thing. Back in mid 1970’s, there was a plug-in car called a Citicar. It used a propane heater for heating and defrosting. As I remember, the heater was not vented, so the windshield would fog up pretty quickly.

You are right, heating (and A/C here in Dallas) will take a lot of power, reducing the battery-only range substantially. I’m not aware of any special tricks they might be contemplating, just starting up the engine sooner, I’d guess. As for the load on the electrical companies, I’m guessing that it’ll be mostly at night, I don’t think that’s a high peak load time.

Long johns, and lots of them. There is no getting around the fact that it requires energy to keep your butt comfortable. This will have a effect on mileage range in a electric car. If there was a propane gas heater then the car would not be all electric.

The BTU requirements for heat can be significant in the northern states during winter. Cooling in summer is tough everywhere albeit not so long in the north. I read once that the A/C system in a car is equivalent to a 2 ton home unit because people want cooling fast and the car interior can get very hot.

On hybrid platforms, there is always the engine that can produce waste heat or run an alternator to power resistance heating. A stock A/C compressor is an option for cooling.

For purely electric cars, it’s a much tougher situation. One possibility that comes to mind is a heat pump. I recently bought one to heat my pool. It has a scroll type pump (only one moving part) and is 7 times more efficient than pure resistance heating. I don’t need cooling so the “waste” cold air is simply exhausted out the top of the unit. They have dual units that both heat and cool. So that would be one option to maximize the HVAC efficiency using known technology only scaled down for a car cabin.

You guys are scaring me! You make it sound like I’ll be going back to the days of driving my 40hp Sea Blue 64 Beetle 1200 with a window scraper in one shaking hand and arriving at school with frost-bitten feet in my boots. Has anyone seen a Volt up close?

When we go to plug in cars, I predict that Stewart Warner will again produce the South Wind gasoline heater and you will need a small gasoline tank to power the heater. For summer air conditioning, the Servel company that made gas refrigerators will start up again and make air conditioning units that run on heat produced by either a propane or gasoline flame.

Any way you look at it, heating and cooling require energy. Maybe we will just have to tough it out as my Dad did when growing up. The Model T had no heater for the winter and certainly no air conditioning for the summer.

Powering the accessories is a MAJOR weakness in all pure electric designs. It’s the main reason GM’s EV-1 electric car failed. You start using heaters, air conditioners, headlights, windshield wipers, sound systems, and the RANGE of the electric car becomes VERY short. So short that Honda has given up on the idea, instead they are developing Diesel hybrids that will be ULE rated and deliver astounding mileage…

It will be interesting how GM deals with the heater issue in the Chevy Volt. In the EV-1, there was no heater…Remember the optional gasoline-fired heaters in the old air-cooled VW Bugs?? Those were fun… Perhaps the gasoline engine will need to be running to power those items. For most Americans, that’s all the time…

TwinTurbo, Sounds like a heat pump would be a solution. Some of you guys need A/C, but not heat. Some need heat, but not A/C.

Would it take a lot of battery to run one?

According to my friends that had VW Bugs back in those days, only wimps opted for the gasoline heater. When we would ride somewhere in the winter in the Rambler that I owned, I would leave the heater off. I didn’t want them to turn into wimps. As soon as they were out of the car, I would turn the heater on. I’ve become such a wimp today that I have air conditioning in my cars. Back in the 1960’s, I wouldn’t think of having such a thing.

Triedaq, I remember South Wind and Eberspacher gas heaters. There was something exciting about driving around with a gasoline fire in front of you on top of your gas tank!

I’m glad someone else is old enough to remember these South Wind heaters. I don’t remember any car fires being caused by this unit. The 1960 Corvair also had a gasoline heater, but Corvair switched to a hot air heater in 1961. It seems to me that either in the late 1950’s or early 1960’s Chrysler offered an optional gasoline booster heater for those who didn’t want to ride in a cold car until the engine warmed up.

Caddyman, I keep replying but it doesn’t go through. Are you talking about a Diesel engine powering a generator/alternator to run electric motors, accessories, etc., like a Diesel-Electric locomotive or like some ships?

What’s “ULE” rated ?

P.S. See previous posts above. I remember those heaters.

I had “air conditioning” in my 64 Bug. On hot days I would turn the vent (wings) windows around backward to direct a blast of outside air at the driver and front passenger. Rear seat people couldn’t even open a window!

A window room AC that can easily heat a 16x16 room is about 10k BTU’s. A AC unit for a small to mid-size car is about 40k BTU. Between the no insulation, all windows, instant cooling…it’s needed.

Heat is also going to be very expensive to generate. It can be done electrically, but it’ll probably cut your driving distance in half OR MORE. Maybe there’s some waste heat from the electric motor (although they usually don’t produce much heat) that can be used.

I’m not old. I just drove old cars a long time ago.

What’s “ULE” rated ?

Ultra Low Emissions.

Diesel can be very dirty compared to gasoline. The new Diesels with the Ultra Low sulfur can be made to be Ultra Low Emissions with the Hybrid. The Diesel Hybrid is just a Diesel engine replacing the gasoline engine that’s is currently being used. Diesel engines get better gas mileage then gasoline engines. Add that to a Hybrid and you have a very very decent and stingy vehicle. A couple articles I’ve read is the Diesel Hybrid can get about 30% BETTER gas mileage over the existing gas/hybrid engine. And it’s a better fit for trucks that require more low-end torque.

Yes, like the Prius, only with a more efficient diesel engine. ULE =“Ultra low Emissions”.

There is a lot going on backstage with diesels. Our refineries can only produce a limited amount of low-surfer diesel. Diesel fuel is now priced about .75 cents more than gasoline because of this. Adding large numbers of new diesel consumers to our vehicle fleet is just not in the cards but Honda is moving in that direction anyway…

Just adding one comment on diesel emissions. Modern diesels are generally very clean engines, but they are not clean in the same ways as gasoline engines. Depending on what you want to measure diesels are a lot cleaner or gasolines are a lot cleaner. When you see one or the other fuel being called dirty or clean, likely the data will be selected to prove whichever the writer likes.

I would like to add that the GM electric car, EV-1, used a heat pump system for heating and cooling. I don’t know what the energy cost was, tho. Too bad they crushed almost every one of them.