Tracking fuel efficiency in the Prime

Any examples of your spread sheets or graphs ?

 

Your car being a plug-in, not sure how much of this is relevant, but some thoughts:

1. At least until the advent of gen 5, Toyota cannot restrain themselves, from lying through their teeth about the mpg. With our gen 3 the fibs settle in around 7.11%, optimistic of course:



2. The only data I take from the car is the odometer reading at fill-up, well plus the the car displayed fuel economy (just for laughs). With the odo number, plus the gas pumped from the receipt, what more do you need:



(Uh oh, gotta fix that last date)

 

Tracking fuel efficiency in the Prime

is this natural

 

Only 2 real fill-ups, last line is my rolling estimate of the next one. kWh are sourced from a separate sheet that has full charge log, used to get them from Kill-A-Watt meter, thats write ?

 

. At least until the advent of gen 5, Toyota cannot restrain themselves, from lying through their teeth about the mpg. With our gen 3 the fibs settle in around 7.11%, optimistic of course:

it is very workabe

 

Anyone with other approaches / ideas / comments that this is waay silly and I should just enjoy the car?

I fully realize that Prius efficiency by itself makes it one of the cheapest cars to drive in the universe, adding charging to it cuts it down any further, so the most expensive part is my time $/hr spent monkeying with spreadsheets


is that write anyone tell me?

 

When you charge the traction battery with 120v ac power source, you are 'filling up the battery fuel tank. Find a way to include that in your fuel mileage records. $/KW charged into the traction battery is a real cost for fuel.

 

You are not the only Gen 5 owner that is commenting about the Prime not being able to separate completely the MPG from the kWh used by MG1 or / and MG2 while providing a separte gauge showing wH of regen braking.

Surely Toyota could be more precise with the general gauges that everyone understands and uses across all the conditions the Prii get exposed to, without having to manually have to do any work on our own to verify what each of us gets for the conditions we drive the car in.

I wonder how many of the gauges in the Prii are completely ignored by the most vocal of dissatisfied owners.

 

I don't let my EV mileage interfere with my fuel economy., but I will have a total running average, once I put all my fillups on a spreadsheet. Every time, I fill the fuel tank, I also record the kms since last fillup.

 

SO you use the miles driven in EV mode plus the total miles drive in the HV mode to calculate miles per gallon. Lumping EV miles with HV miles and only considering the gallons of gas burned, neglecting the KW electric used, seems to me would give you a false MPG.

 

I don't deny that at all. The only meaningful result will be my fuel costs, as part of my combined driving.
I believe I can also derive some EV information from my car's computer.

 

Your fuel cost is not your gasoline fuel cost ($/gallon) alone, fuel cost should include your electrical fuel cost ($/KWH). The cost of importing a KWH of electrical fuel is a fuel cost just as the cost of adding a gallon of gas to your fuel tank is a fuel cost. In my case, importing electrical fuel works out to be about the same $/mile cost as importing gasoline fuel cost (at gasoline $4.50/gallon, electrical $0.32/KWH). If you leave this cost out of your $/mile fuel economy calc, you are fooling yourself.

 

We should call it MPGe to silence the critics!!

I see where your coming from, but I have better things to do with my time than worry about things I can't change.
I'm on timed rate of use and got my Prime registered with my utility company. EV charging discounts applies between midnight to six AM; so that's how my charge timer is set. Take my EV monthly discount usage and reverse math the actual cost, then add it to the cars fuel expense; under Efuel. That'll give me actual monthly fuel usage, so I can easily calculate actual cost of the car. IMHO, It's more reliable than trusting the car's calculations - since they can't even fix their app to work correctly.

YMMV

 

I doubt there is any way to silence the critics here or anywhere else, at least not for a sustained amount of time. Wouldn't it be nice - if it were possible.

Our local utility just hired a third party to administer it's new EV charging discount program. I skimmed the details a couple days ago. Two tiers with a yearly commitment for either, offering an upfront quarterly payment to either of two listed online payment vendors to the email on file with the utility and bonus points for percentage of usage in the discounted time. Any charging above the minimum 80% of vehicle charging within the discounted time frame qualifies for bonus points to be payed on a quarterly basis. Below 80% vehicle charging in the discounted time frame disqualifies for that quarters payment. Vehicle or EVSE must be audit-able by the administering agency, qualifying EVSEs and vehicles are listed, Prime is on the list. ~(\/)~
( level 1 ) is not supported at current (pun intended, NOT) time.

It might have been nice 5 years ago, when I charged full twice a day, not so much at this time.
I've even switched to 8 amp charge setting currently when temps dip below freezing.

And I couldn't care less about there being more losses in the calculation at the lower charge setting
than when the Prime is set at its Max Charge rate.

I wouldn't be at all surprised if one or more of the old Tesla early adopter / advertising group here even remembers pushing that agenda in regards to the benefits of charging speed at the plug, unless they want to try their mafhs skills on it again for our 4, 9 or 12 kWh packs, please.

I was able to verify using the gauges in the car that the accepted (by me anyways) losses from plug through pack to wheel is approximately 6.6 kW at the plug, 5.5 kW pack to MG1 or / and 2, 4.5 kW where the tires meet pavement.(posted here 8 years ago several times) But it can't be done / verified using the gauges in the car at (normal daily driving speeds ), at least I couldn't.

On another note, I'm currently tracking utility usage for the home, which includes the Prime as a secondary expense, , not a primary one, like it might have been closer to, when being fully charged twice a day and adding 12 - ( 14 winter) kW per day to the electric bill. More if a third charge per day was added on weekend days.

Things I track daily for home usage are electric, natural gas, current temp several times a day, daily hi temp, daily low temp. wind speed and direction, sun/cloud/ rain/snow in a text based daily journal. Plan is to add each as a database record when / if I get time and motivation. For now the text base journal seems to always be evolving in one way or another.

Was curious if the reduced rate program you posed above is similar to what I read in the terms of our newly offered reduced rate program.

The terms remind me of the reduced rate bye back of grid tired solar. kinda sucks from where I'm looking at it from..

 

I get $0.015 discount per KwH burned between 0000 to 0600. The assumption is all that power is going into the traction battery. I'm sure it's off by a few KwH, but close enough for government work.
Your utility contractor seems to be making your program more complicated than it needs to be and don't even get me started on how they plan on auditing that 80% threshold BS....

 

To be kind, my summary wasn't the best at outlining the program, although it sounds like you got most of it as posted above.
To make it more clear ( hopefully ), either the telemetry of the car or the telemetry from one of the approved / listed EVSEs is the core of the program, so a charge usage timer from either the car or EVSE is what they are going to use in their calculations. And 80% of vehicle charging needs to be within the reduced rate time frame.
The other thing that was bad is the two tier - basic $25 advance get $150 - upfront one time only joining payment for one year commitment to the program.
I'll assume that bonus stuff is about as useful as credit card bonus points. If I had a million dollars
On another hand, I might still use green stamps, if they still offered um
finally ~(\/)~ should have been ~(/\)~ or

 

The problem here is that Toyota can't fix their app, so chances are you're not going to get that discount (dangling carrot on the end of the stick); If the car doesn't report, what happens?????

 

I've got my own ideas about the app that don't necessarily mesh with the popular dis-satisfaction. Besides if the vendor couldn't access the prime for it's charging stats, I doubt they'd list it. (Things airn't always as they would appear from hundreds of post about a subject in this forum.

Plus, I'm not interested in the data the app is supposed to be able to provide, but doesn't for whatever reasons it doesn't provide it. Even if Toyota lists it as supporting Gen4 and 5. And I'm not interested in the Program offered by my utilities 3rd party vendor or getting an account with a online payment sharing service for access to the funds. Man that is a lot of dis interest on my part. Didn't mean to make it sound like I was actually thinking about using it. At the amount I currently charge the Prime I'd be able to get to 80% charging in the discounted time frame in my sleep. (probably a double entendre there )
I do check my utilities web site once or twice a year to see what new ECO programs they offer, but so far I haven't been interested in any of the so called offering to save money on our bills that I've seen so far.

Much like our states recent ads for rebates on cold weather heat pumps, to help save the planet by switching to electric based heat so the nuclear reactor 20 miles away can do it's thing. I already had my fill of electric baseboard heat in a one bedroom apt heating only the bedroom during winter in this town.