Heat Pump? Check! Steering-Wheel Warmer? Check!

32°F here in Minnesota. We've been getting very wet snow here all day.

Just a few minutes ago, I was at the grocery store giving the remote-climate feature a test for the first time using the "Max Heat" setting. Plugged in, I wanted to see how much electricity could be used to recharge the battery-pack with that much demand from the heat-pump.

Knowing that max uses far more electricity than just at setting of 65°F with ECO, having to wait so long for this test was a big deal. Way back in 2010 when Toyota provided me with a prototype plug-in Prius to play with, it was August and the decision had been to not include a heat-pump.

Anywho, in the 12 minutes I was away from the car, the charger provide 0.64 kWh of electricity (at a steady rate of 3.16 kW). That resulted in only an estimated 1.3 miles of electricity being added to EV range, but the interior of the Prime was toasty. Sweet!

And yes, interior heating takes quite a bit more electricity than cooling. Fortunately, we get a high-efficiency heater... a vapor-injected heat-pump, which better than both the regular type of heat-pump and quite a bit better than the resistance type.

 

Mid thirties here one morning so I too used the heat pump and heated steering wheel. Wow, probably the biggest improvement over the PiP. Usually on those mornings in the PiP I'd have to open the windows so they wouldn't fog up if I didn't turn on the heat. Now I got to work comfortable and fog free.

It seemed to me, the EV range dropped a little over mile, about what it used on the PiP when I used A/C. But I got that mile back when I left work later that day and turned off climate control.

 

Haven't yet used the heated seats or the heated steering wheel. But I have tried the heat pump while in EV mode. Works. In fact, it is scary how FAST it works and gets warm. No ICE start at all (yet). The temps have been hovering around 30-40 with some 20's predicted in the next 48 hours.

I also haven't tried scheduled charges, with or without the heating feature while charging. I am unsure about just plugging it in unscheduled (as I have been doing all along) at such low temperatures outside. Might that hurt the batteries? I don't have a usable garage. L2 charger.

 

No reason for concern. The system monitors battery temperature and adjusts charging-rate accordingly.

My Prius PHV endured 5 winters in Minnesota without the benefit of Prime's battery warmer.

 

82°F back in June, the 7.5 mile drive to the coffeeshop took 19% capacity.

34°F a few minutes ago, that same 7.5 mile drive to the coffeeshop took 29% capacity.

Increased resistance from outside air, reduced efficiency from battery, combined with the electric-heater set to 65°F in ECO revealed the harsh effects of Winter.

For me, that means my 19 miles of commute each way should remain in EV. The catch is that drive-time can be dramatically longer in on snowy days. Fortunately, those don't actually happen often. It's mostly just continuous sub-freezing temperatures for many weeks in a row. Obviously on those days when it dips down near 0°F and below, running the engine will be a welcome addition to heat provision.

Regardless of Winter conditions, the resulting MPG will be outstanding. Also having the benefit of pre-conditioning the interior using electricity directly from the grid will be a very nice bonus.

 

Just did a COSTCO trip beginning with 100% from the full charge last night. Used 61% of the charge at 40 degrees F that the same trip would have used 45% at 65 degrees. That's quite a difference - but not unexpected. Heat was off, but I did try the heated steering wheel for a half minute. As it gets colder I can see myself just driving in HV mode, and keeping it there, throughout the winter as I de-ice and warm the car up car 3 out of every 4 days.

 

No, but I measured one full cycle of remote climate on MAX HEAT. It uses 0.37 kWh.

 

What were you doing driving at two o'clock in the morning?

 

From stats for a company that sells aftermarket seat heaters that are also used by most of the OEMs, Heizgerat Setzt, they quote they use about 70 watts. Most of the aftermarket seat heaters use carbon heating elements as do the OEMs and the kits come with a 10 amp fuse so that’s probably right. The steering wheel heaters probably use much smaller carbon elements and I would be surprised if that uses 50 watts.


Unsupervised!

 

I'm going to try to redirect the electricity going into the seat and steering wheel warmers back into the traction battery to see if that recharges it and gives me more range.

 

Well I guess it's cooler in Austin than College Station which is where I will be for a week starting tomorrow. Highs there in the 80's, and right now at 1:00am in College Station it's 55 according to Accuweather. So then what am I doing up at 2:00am in Atlanta? Just finished watching the five plus hour Astros vs. Dodgers World Series game of course