Playing With ‘24 PP XSE Mileage On The Interstate

The EV ratio also includes the times the engine was off while HV mode. That said, I'm sure your EV mode miles went over the system's prediction. Did you make note of the SOC level before and after?

Can't say if this is actually better. The car would turn off the engine while coasting down the slopes in HV mode. Switching to EV mode would be a more reliable way to keep in Ev operation instead of fine pedal control. Need to repeat the trip in just HV to see the difference. A thorough test would also repeat with leaving it in EV mode until the range was depleted, and even one with the EV range already gone.

 

Switching modes in a Prime has it's own set of rules. It's possible that switching to EV and gliding downstream can provide more regen. Best of luck trying to quantify the difference in regen on a 100 mile trip or longer switching modes. I can't wait to read your observations from your planned shorter trips.

maps show Albany to Newton at 161 mi. Where in CT did your finish your drive?

 

Thanks for the update, I'm interested cause I travel those routes too, last time to Mansfield late Nov 2023 and other times to Webster, Norwich or Deep River.
The EV/HV thing in the Prime can be as easy as pushing the right button or letting EV range run out and letting the car switch automatically. The behavior can change quite a bit summer to winter and not just MPG wise. Having a routine that's repeatable under the same conditions can make it a lot easier to begin to understand what is going on when the car switches over. It's even more helpful if you can get the car to switchover at roughly the same place and/or time. Not many owners have the time or patience to feel out the car that way, but if you're into the MPGe thing there are lots of thing the Prime can show if given the chance.

 

Even if you don't switch to EV mode, I'm sure the car on a long drive will still do really well if it has EV range in terms of MPGe.

I don't know if they test the MPG ratings for EPA with 0% SOC or not. But even in HV mode driving down the freeway for a shorter distance of 20-30kms, I find the EV mode kicks on when cruising quite often. And in traffic the EV mode kicks on and stays on for long stretches too.

With the bigger battery it probably favours EV mode while in HV mode more than the normal prius would too. I mean, one can assume the normal prius with a smaller battery will have a smaller amount of "operation in EV mode" available so likely accesses it less often? Then again when in HV mode the car likes to target 75-80% SOC on the dash for EV reserve in HV mode. So maybe it does use the same algo as the regular prius when in that mode.

 

Wow! That's GREAT for interstate highway miles. Couple of questions. Was the speed limit 70, and did you maintain it or go faster? Did you use cruise control? I've found that in my 2017 Prius II, I can get an avg of 60mpg in normal city/highway as long as I: 1. Use cruise control whenever possible (let the car do the downhill re-gening) 2. Do the speed limit.

 

I consciously switch between Auto/EV and HV mode when driving. On the highways/freeways, I always have it in HV mode with no need to switch to EV mode on downhill portion; the car will auto switch between HV and EV itself on those sections. When driving in the city or small towns, I switch to Auto/EV mode. Took a 60 mile road trip yesterday (120 miles total) to Corvallis and back using 99W and averaged over 67 mpg both ways.