Can someone explain why the gas mileage is so terrible in cold weather, does the Volt not have a heater core? When I need heat I run the car in Hold rather than normal. Last night it was close to 0 so I had the heat on. The MPGe was awful as expected, 59MPGe, but so was the gas mileage, 33MPG, even though it was all highway. I under stand why the MPGe is so bad, batteries don't do well in the cold and the electric heater draws almost as much current as the engine, but why was the gas mileage just as bad? I've been operating under the assumption that heat would be free when running the ICE because internal combustion engines produce vast amounts of heat. Does the Volt not harness that heat? Is it always using the electric heater or is thee another reason why the MPG is so low?