How to use Fuelly with Prius Prime?

Fuelly simply isn't set up to handle dual or bi fuel vehicles.

 

You'd have to estimate electric use represented by 30mi/kWh (allows for losses / charging & discharging) then factor that into your fuelly data. It's about the best you can do.
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They are all entering gal gas used for distance driven, just like any ICE car. Ignoring EV portion driven from the wall charge. By definition, that is an accurate mpg.That's why the MPG displaying on PHEV is totally meaningless.

Posted via the PriusChat mobile app.

 

note how more or less driving on gas or straight ev makes a lot of difference in overall economy .... some will be mostly gas while others just ev. Our Volt at 70K miles (for instance) has run ~90% of the time on electrons. Yet it's had over 6K miles of high speed cross country runs - besides driving over its (epa) 54 ev miles on rare occasions. That's resulted in a lifetime overall average of almost 80mpg .... even tho its gas only gets ~42mpg epa.
Maybe some day fuelly will be able to account for varrying fuels.

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What does it actually do for you? Help you change your driving habits?

I don't use it. I just drive as economically as I can in different situations.
But, I'm not a data freak or into spreadsheets or pie charts so there's that.

 

They may. But for a PHEV, unless the owner keeps a record of the kWh electricity used from the wall to charge the battery and distinguishes the miles driven by gas vs miles driven by wall charge, it is not possible to report accurate MPG for the gas portion. Gen4PP did not have the ability to record kWh used from the wall, nor did it display the actual miles driven strictly on the wall charge. I suspect Gen5PP is similar to Gen4PP in that regard.

My current Escape PHEV reports kWh used from the wall for each charge session but does not keep the record anywhere. If I do not check the app and write down the amount of kWh on a spreadsheet, the data is lost. I double-check the app value against the actual kWh from the wall using a watt meter. It seems the App value is the actual kWh charged into the traction battery as they are always ~7% lower than the actual kWh drawn from the wall. Escape PHEV is just like PPs in that it does not report the miles driven on EV from the wall charge. So, there is no way to accurately calculate the MPG on the gas-only portion of the distance driven.

 

i've never seen a 240v kWh meter other than the expensive / separate kWh meter some utility companies allow to be installed - to deliberately separate out car charge use. Even those don't calc' for ac/dc conversion losses .

 

Using 120v L1 EVSE supplied by Ford. The difference between the watt-meter measures at the wall and the kWh charge at the traction battery reported by FordApp has been an average of 6.42% with a range of 3.66%-11.48%. I have used L2 EVSE at work to charge, but since it is not a commercial charger, it does not report the kWh used for the charge session. So, I don't know how much better the conversion efficiency is compared to L1 EVSE. In any case, your "28% to 34% loss" is crazily high. There has to be something off.

 

I'm confused by your question on using Fuelly for tracking mpg. Are you really asking about mpge?

I simply enter miles driven, gallons used to fill up and cost per gallon. To calculate total cost per mile, I use total $ spent on fuel plus the estimated cost of electricity (.06 per kWh) divided by miles driven over a longer period of time, like a month.I use a watt wall meter to more accurately track the electric used to charge the battery.

 

Yes.

 

Okay so from what I've read, the energy contained in 1 gallon of gas equals 33.7 kWh. So when calculating what your "actual" mpg is, you can add the amount of equivalent "electric" gallons (based on actual kWh used to charge the battery) to the total actual gallons used to get a more accurate picture of total mpg.

 

I still use it out of habit more than anything. I still track my other cars in it. For my Prime, I'm not expecting anything super accurate for efficiency. I still like to see the trend of gas prices and tracking mileage.

 

Like some have said. I just use the amount of gas I put in and divide by the number of miles driven. That includes my EV miles. I only have one Prius Prime. The other one I passed on to a relative. So, I don't track the miles anymore on that one.

 

you mean - like it was suggested in post #3 ??

yea - that IS why the MPGe notion arose . Some plugins multi-function screens will actually divvy up the figures & then combine the result for you
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That is what the mpge figure is.

 

To answer the title question: just never plug in.