LP gas fired heater / range extender




Offer a gas or gasoline-powered heater and range extender.


As part of the cold weather package, add an LP gas (or similar) heating element as heat pump backup heat, in place of resistance strip heat. A standard residential gas grill bottle would fit in the front trunk/microwave area, and a vent would be provided to the windshield/wiper area, with suitable thermal controls, to add external defrost functionality. A catalytic heater of the type carried in pockets by outdoorsmen would be an interesting trade alternative to this concept. Either would add emissions, but they would be trivial compared with those of a range-extending internal combustion engine or fuel cell and would accomplish much the same extension of range.

Moderator: Sorry, but can’t see any value in duplicating the existing heating system with a second system that adds cost, weight, a significant safety risk, consumes cargo space and goes against the entire Tesla concept.


We’re closing this out as we don’t see any chance Tesla will do this.


lightly edited by moderator
Category: CY3XS Applies to:
     Created 5-Feb-2014
Thom EM

1 Comment

To address the editor's point that this seems to duplicate the existing HVAC system: It would replace *only* the electric resistance or auxiliary heat part of the existing system.

The heat pump would provide heat from battery power up to its limit, as is the case now. Then, instead of turning electrical energy back to heat to supplement the heat pump in ultra cold weather, the additional needed heat would come directly from fossil fuel. Such a system could also pre-warm the batteries if they have to be cold soaked when no charger outlet is available.

Given that providing resistance heat to the cabin can easily double or even triple the electric consumption in very cold weather, the addition of fossil fuel heat could dramatically extend the driving range under such conditions, for given battery size.


There's a serious discussion in the green vehicle press about using fuel cells as range extenders and heaters, because they are somewhat wasteful of heat, though not as bad as ICEs. The Toyota CEO recently took digs at BEVs on the grounds that FCVs would lose less range in cold weather because they have this waste heat to use. But a simple fuel fired heater would give the same effect while assuring that zero heat would ever be wasted. It would always be used purely to extend the electromotive range by providing needed cabin heat that would otherwise come from the battery.

For those purchasing a subzero package now, it seems to me this could make sense. The same problem arises in heating a home with electricity. The heat pump is ineffective at very large temperature differentials, and resistance heat consumes 2-4x as much power compared with the heat pump. Quite a few newer homes are using heat pumps with fossil fuel backup to keep electric bills under control. Admittedly, the advantage would disappear as fuel costs rise and exceed electricity costs per unit energy, so eventually it will be less expensive to simply use larger batteries than we currently have available. In the meantime, there is nothing unsafe about a catalytic heater, and it would address this issue head on for colder climates, until such time as bigger batteries can be made available and charged at costs comparable with fossil fuels.
    Created 6-Feb-2014
Thom EM