Winter Charging Strategy

Well, it was last winter but THIS YEAR (2018) in January .

The original question was whether heat pump would come on or not if the remote AC is pushed for preconditioning when ambient temp is below 14F. I already knew that the heat pump would not be effective below 14F for heating and ICE would come on during driving. However, from my experiment, apparently heat pump still turns on and runs using traction battery, despite having almost no effect on heating up cabin temp. Therefore, in very severe cold climate PRIME's preconditioning feature is useless. Only way to preheat my car before morning departure is to run outside, unplug the charge cord, and turn the car READY at which point ICE comes on immediately even if traction battery is fully charged. I have given up driving EV in the morning during coldest month of winter from Dec to Feb, and used HV exclusively for my morning commute. My rationale is that if ICE comes on anyway for heating the cabin, as might as well use it for traction, and save the battery charge for the commute back to home in the afternoon.

 

When the temperature is below 13 Fahrenheit I unplug the car and start it up and use the defrost. The ice comes on and it heats up the car. Of course the battery is fully charged and so when I engage the car I drive hybrid mode and I turned off the defroster and use the AC mode to heat the car. Because I'm going to ice it seems that the heat pump icon is on so I'm a little confused about what's heating if it they ice plus the heat pump and conjunction. But it works. When I first got the car I use the heat pump to preheat the car and the only problem was I got a lot of moisture with the snow being on a car and it didn't melt it. Had to go to the defrost with the ice on.

Posted via the PriusChat mobile app.

 

The heat pump is being used to dry the air and prevent condensation while the ICE heats.