[bennelson]

It's getting cold again.

All summer, I don't bother a bit about heat in the electric car. Today, I was working on location out of the trunk of my car. I had to wait a while for someone else, and don't have a heater in the car for the moment.

It was pretty cold. Which gets me back on the topic of heating an electric car.

My car has mostly just been a 72V system, running on used batteries.
I have a 150 watt heater UNDER my batteries in the rear box to warm them a tad. I ran that for maybe an hour this morning before I had to leave.

Last winter, I just set a household (120V AC) heater in the car behind the passenger seat. I ran that on a timer to heat up in the morning, running off wall power. When I would drive off, the whole inside of the car was already warm, and the heater would stay warm for about 10 minutes or so.

The only down-side to that is the heater takes up some space.

Other ideas that I have had include:

Reusing the original heater core, but with a small dedicated coolant tank rigged up to it with a "pumping-type" block heater rigged up to it.

Removing the heater core, and replacing with an electric heating element.

12V electric blanket.

Motorcycle-style heated jacket and/or gloves

Heated seat cover made from heat-tape sewn into cloth material (removable for summer!)


Ideally, you want to put the heat where you need it, to be most efficient. A heated jacket is more efficient than a heated car, if you just need to keep the person warm.

Maybe a two-part approach is best - I want to heat me AND the windshield (to keep from fogging up), and ideally, pre-heat the car cabin from wall power (rather than the batteries) when parked in my garage.

I guess a cabin heater that could run on AC OR DC would be nice. Relays could be used to connect/disconnect it from/to one circuit or the other when the charger is plugged in.

Maybe a heated seat cover would be the best way to heat a person. Heat tape isn't that expensive, but it IS designed for 120V AC. I wonder how well it might run on 72V? My under-battery box heater is about 130 watts of heat tape. Sure sounds more efficient than running a 1500 watt electric heater!

Anyways, throw out your winter electric car heating ideas!

-Ben


PS: I am also considering upgrading the car to 108V. That would be three more batteries. It all depends on the EXACT spacing of items under the hood for if I could cram them under there or not. My charger is variable, and goes up to a maximum of a 108V system. I would imagine that many 120V heaters would work fine on 108V DC.