HV Only Gas Mileage

FYI if you set the ACC speed on a descent the car will use regen to maintain the set speed, which is a nice thing that a regular ICE-powered car can't do.

 

I think the electric heat is coming on in HV mode for the heater even when the engine coolant is hot.
The engine runs longer to replace lost charge.
If I wear a coat and leave the heater temp on low, I can get summertime MPG.
Hope I'm wrong.

 

I've had the car fully recharge to 100% on a long downhill.

 

My recent trip also seems like the electric heater is drawing power, even when the ICE is warm in HV mode.

I just had a 'bad' trip from WI to NY. (NY to WI had been much better). Cold temps, snow and ice from WI to Chicago, in HV mode, and the battery went from 36 to 0 EV range (11% charge). Seemed like the heater was seriously affecting EV range, even though I was in HV mode.

I drove with 0 EV range for about 600 miles, and got less than 35 mpg. My average was 45 mpg in warmer weather on the trip NY to WI.

On the WI to NY trip (EV range = 0), the SOC would drop to 6%, then ICE would rev and build charge to 12%, and rpm would drop slightly while SOC dropped back to 6% and rev again. Very rarely got into gear mode. I switched to HV charge a couple times to get a little more battery, but it quickly disappeared. It held charge much better on the trip going out: same speed, same road.

I drove 77-80 mph (ACC set at 80 - Speed limit 70) for both trips.

 

Just finished a round trip Boston to Burlington VT trip. Temps in the mid 50s both ways with 3 people plus luggage in the car. Cruise control set to 74 the whole time. Got 38 mpg combined on the trip in all HV mode. No car I ever owned that seats 5 got that kind of mileage.

I noticed almost no loss of battery range on the trip. I was paying fairly close attention to the battery discharge and recharge rates because some other posters noticed that there was battery loss on long HV trips. Had a few periods where the engine was running at a higher noise level then normal but I was listening for it so I noticed it more then I would have in a different car. I’m spoiled by the quiet running the way I normally drive the car. I’m sure if I wasn’t paying attention for engine noise i wouldn’t have noticed it at all. Setting the music volume to 11 drowns our the engine completely.

Going through the mountains in New Hampshire and Vermont the car kept pace with traffic and had no trouble at all on the highway.

BTW - the Ben and Jerry’s in Waterbury VT has free charging. Just sayin!