Plug in MPG?

[jerryliebler]

Originally Posted by trollbait

You could set up a profile for just HV miles, one for just EV miles, and another for both.

The real issue is making sure the dash display is actually what you think it is. The HV to EV ratio is actually what you think it is; the ratio of what mode the car is in. The new Prime on the other hand reports anytime the ICE shuts off as EV miles. So the EV percentage includes electricity used from the grid and made from gasoline.

The other thing is that the dash display is likely using how electricity was used from the battery for calculations. Because of charging losses, that isn't the electricity that was put into the car. You need a Kill-a-Watt on the EVSE that came with the car, or a level 2 EVSE that tracks kWh used. The EPA numbers assume an average charging loss from a level 2 unit.

After trying to enter my most recent tank, as a starting point, I am inclined to simply give up! This site computes miles by the difference of odometer readings and gallons are what is input meaning that the only possible correction would be to input "adjusted" gallons (adding the electrical input equivalent). Even if everybody did this, it would still look like those who can use more electricity are better "hypermilers". I'm quite sure the car does the right thing in recording as EV miles miles driven in EV mode (even if the ICE is on) and HV miles when the HV mode is selected (even if battery power is used) I know this because I start most trips in HV mode and use no EV miles even though I use some battery power during warm up for example. I also have dramatically inflated my EV miles by selecting EV mode to kill the ICE in a downhill glide beginning at 62MPH. I've changed how I enter the high speed glide and now after confirming ICE off I shift to N then go back to HV mode. Unfortunately N doesn't allow regen but at least the miles are scored more appropriately. Regrettably the KW use reported by the car is only whole numbers I'm going to deploy my Kill-A-Watt to get better data on charge input. FWIW The spread sheet at Prius Chat records and computes the "right stuff" to compare hyper-miling success against a peer group of first gen PIPs
If the Prime behaves as you say, I do believe Toyota screwed up and gave me another reason not to "upgrade"!