It has been a long time since I posted, my car (a '23 Prime) continues to plunk away trouble-free after the initial 12V battery replacement--which was partially my fault. I'm at 49K miles in 2.5 years, so driving quite a bit. No posts recently since it's become the utility vehicle I was hoping it would be! It just works. I would like to check on something I've assumed, but realized may not be accurate. I don't mind trading a little discomfort for mileage, so rarely turn on cabin heat in EV mode since that is a battery killer. My assumption is on a longer trip, once I drain the battery and the engine warms up, cabin heat is now "free" like it would be in any ICE car or indeed regular hybrid. Does anyone know if that is actually true? Once the engine warms up, does cabin heat come from engine waste heat? I would hope so, but the HVAC for a Prime/PHEV is so complicated I wonder if maybe it isn't entirely true. will
For those of us who live in cold climates, driving without interior heat is not an option. Nevertheless, heated seats and heated steering wheel are welcome.
Of course, it is not free if you turn on the A/C (heat pump), which uses a lot of electricity. But: If you don’t turn on the A/C (heat pump), you can still get some heat from the heater core, which circulates engine coolant. Adjust the temperature to the desired heat. You can turn on the fan only without the A/C (heat pump) and still adjust the temperature. The fan alone should not use that much electricity. I need to turn on the A/C (heat pump) occasionally in Southern California because the windshield fogs up. I then set it to DEF vents. It is more efficient than using the DEF button, which is much more aggressive and also activates the mirror defoggers.
Studies have shown that people who put up with cold weather regularly live longer and stay healthy longer... And yes it is true the ICE heat is the most efficient source of cabin heating costing less than pennies on the dollar via what you pay as mpg. One thing that could change this is battery pack temperature optimization. The battery runs most efficient at very specific temperatures. And being able to monitor that temperature and how efficient the car manages it versus you needing to manage is significant. It may well be that lots of cabin heat in cold weather improves EV range in some scenarios. On one end of the spectrum you have a Prime like yours living in a heated garage and plugged in. On the other end of the spectrum you have a Prime like yours living on the street with no home charging in sub-freezing temperatures.
I owe the fact that I am still alive to the fact that I have tried to eliminate all stress in my life. Endlessly fine-tuning settings and driving habits to extract maximum fuel economy is not my idea of reducing stress. I am happy to take the benefits of driving my car normally. I know I am reaping an enormous benefit just by owning a Prius.
I believe the Prime has a heat pump so it still uses electric in Hybrid node.That is my guess. Otherwise in EV mode the heat pump would need to heat up engine coolant too, which would be counter-productive,
