Hi, Reason for this post: I'm posting this suggestion for Tesla here because at the most recent SH Meeting Elon said that the best way to make a suggestion would be to post it on either the TMC Forums, or the Tesla Motors Forums. He said that they check for popular ideas, so if you would like Tesla to invest the engineering required to determine if this idea can be implemented cost effectively please respond to the poll and reply to the thread if you have any further suggestions or comments you want to add. I hope that I'm making this suggestion in time to be implemented for the M3 Launch. If you agree that this would be a desirable M3 feature please let us know. I believe that if it's feasible, Tesla cculd design a system that can easily be added to all of their cars so even if they have already passed "pencil down", I believe that they could add this feature to the M3 without having a negative impact on their schedule. IMO at least taking the time to investigate this idea thoroughly is a no-brainer because this would completely eliminate the decreased range in cold weather plus it would provide increased passenger comfort. The Idea: This is based on a post, a long time ago (I don't remember where but not TMC), in which someone stated that he heated his EV with a DeLonghi Oil Filled Radiant Heater while his EV was connected to the grid, then on his commute to work the stored heat maintained the passenger compartment at a comfortable temperature. Tesla's have the ability to preheat or cool the passenger area, while they are connected to the grid. If the car heated containers filled with oil, or phase change materials with sufficient thermal mass to maintain a comfortable temperature for as long as necessary, the range of their cars would be substantially improved in cold weather. For traveling the capability to travel the distance between Superchargers without requiring any supplemental cabin heat would be ideal. The other major benefit would be that radiant heat is a very comfortable type of heat. Is it Feasible (Cost Effective)?: Is it possible, and is the solution affordable, to store sufficient heat to maintain a passenger compartment at a comfortable temperature, in a cold climate, for the time it takes to exhaust the batteries of Tesla's? Would it weigh too much? Could the same storage medium be efficiently used to for cooling as well as heating? Consumer Reports review of the Model S states that: Implementation Possibilities: Using phase change materials for thermal storage, seems like a good match for EV heater use, or something simpler, like oil if phase change materials are not cost effective: Thermal Mass | Sustainability Workshop Best Approach?: I can think of two possible approaches, which might be combined. 1. A big slab or slabs of phase change materials, possibly covering the entire floor under the carpets and/or on the doors. This "system" could be as simple heating the space, which would heat the slabs. The disadvantage would probably be (unless the storage medium is insulated) that it would be more difficult to heat the cabin using the on board heating system, if necessary when the car is not connected to the grid. 2. Some approximately brief case sized containers filled with either a phase change material or something simpler, like oil if that will work well enough. I think that good possible locations for these containers would be one per seat, either on the bottom of the seat, or on the floor beneath the seats. Resting your feet on a warm container would feel great on a cold day! Insulated Containers?: I don't know if insulating the containers would be cost effective or not, but insulated containers with vents, which could be opened and closed, would have two advantages. This would allow the thermal mass to be heated to a higher temperature (store more heat), and storing the heat for later use. For example the vents could be opened sufficiently to maintain a comfortable temperature for your morning drive, then closed when you arrive at your destination, then opened again in the evening, with hopefully sufficient stored heat to maintain a comfortable temperature for your return home. If necessary fans could be used to extract hot or cold air more rapidly.