How to manage EV Range

Switch to EV mode on the freeway. It'll use the battery and operate the gas engine at lower rpm. We call it EV-BOOST.

 

Like usb said, use EV on the freeway. Try using HV while accelerating and switch over to EV after you get to the cruising speed. This may give you more EV miles.

 

If it is safe to do so you could switch to EV mode 5 miles from home and drive under 62 mph on the freeway. This is what I do. I always have leftover EV coming home and I use it up in the right lanes with trucks that are going under that speed anyway.

 

Every time I see this referenced a bit of me dies inside...

Darned (as you might put it) Euro-spec PiPs!

 

And the "under 62 mph"... Looks like a mistype to us!

 

Yes, I think there is a bit of hysteresis from 62 - 65 mph.

Mike

 

Did you use up all EV miles today?

 

You could try a simpler method. PiP starts in EV mode by default. Don't touch the EV/HV button. Let it do it's thing and it'll use up all the EV miles before you get to work.

 

I’m interested in the “EV boost” idea. It’s not clear to me how it works or how it helps improve mpg at freeway speeds. I usually try to cruise at 70 mph (65 mph limit). At that speed I think the ICE is generating propulsion. How does the battery get involved? Assume there are still 10 miles of EV showing on the display and I will be travelling 25 miles.

 

EV boost is when you are in EV mode but you speed up to >62 mph. The gas engine comes on. And then the engine and battery share the work to propel the car. It is a bit difficult to precisely measure the improvement...but you can definely see 70 - 80 mpg, for example on a trip of 20 - 50 miles. If you just drove 10 miles in EV (at less than 62 mph) and then the remainder in HV you might see the same net mpg. But with EV boost you are driving >62 mph (roughly) the whole time.

Mike

 

Prius gas engine is an amazing combustion engine. It can be at near peak efficiency while producing the lowly 13hp (around 1,000 rpm), thanks to the combination of Atkinson cycle and EGR.

At 70 mph, say you would need ~20hp. The PHV battery can fill in 7hp and keep the gas engine at 1,000 rpm. The flexibility of eCVT makes this possible.

To my knowledge, EV-BOOST is unique to PiP as it requires an efficient operation at very low partial load. Ford Energi gas engine will not be able to do it since the displacement is larger (2.0 vs 1.8) and the lack of EGR. On top of that, Energi models were geared differently to allow higher EV speed (85 mph).

 

So, if I do the speed limit of 65 mph, which of the buttons on the console do I need to push for EV Boost to occur? I have been pushing the HV button because I know the engine will be on at greater than 62 mph. I push the HV button about a mile before approaching the on ramp to make it easier to blend into traffic. I want to have the engine warmed up a bit to give me the increased power I need to avoid the 18 wheelers chugging along at 70 mph. Here in MA, the 65 mph speed limit is just a good idea.

 

The button is a toggle. Just press it again to switch back to EV. When traveling faster than 62 mph, the engine will continue to spin but either use less fuel or none at all. It takes very little horsepower to maintain a cruise at 65 mph. You'll see the MPG pegged at 100 even though the engine isn't stopped.

The purpose of BOOST is to provide more electricity than usual. The result is higher MPG.

That isn't necessary. Drop the pedal to the floor with the engine still cold. Watch what happens. You can override the 1500 RPM limit that's used for clean & efficient warm-up. That power is there if you need it.

 

Please don't do that frequently though.

 

I haven't ever actually needed to.

Someone had to verify it was indeed available; otherwise, we'd have new owners turning on their engines sooner and missing out on efficiency opportunities.