My electric cost if I take my total electric bill and divide by my usage is .18 per kwh. Using my info below what is my cost per kwh? The info below is my total for the mileage of 2245. I did not reset meter. In that number 765.5 is gas miles and 1,479.5 is electric miles. My gas mpg was mostly on highway traveling 60 to 70 miles. My electric miles were mostly local with probably 10% highway. The gas Mpg I calculated for the 1st 10 gallons was 40 and for the next 8.5 gallon fill up was 43. I am not sure why I did better on the 2nd calculation, it was the same route, same traffic, and same kind of gas. Hopefully this is the normal mpg, but both were good considering on highways near Boston. I was using AC for all highway miles, but not for all electric. Actually it was probably warmer during 1st 10 gallons, so the AC was probably working harder.
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Calculating cost per kwh
Robin2
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So what kind of percentage drop do you see from what the display in the car claims and what you measure? I would think the loss might be pretty similar for most people.
This needs to be brought to the attention of whoever controls electricity costs in those states. I'm in CA and I find it ridiculous that CA officials are trying to ban gas cars, trying to encourage and force everyone to start using electric cars, but then they turn around and make it ridiculously expensive to drive an electric car. Even with the high gas costs, the costs for electricity are higher.
To give you an example, CA has several different rate plans you can pick from. The cheapest EV plan gives you a rate of .15 cents per kWh between midnight and 6 a.m. Between 4pm and 9pm in winter you pay almost .50 per kWh but in the summer that rate goes up to about .85 per kWh. Then the rest of the time that's not between 4pm and 9pm or midnight to 6am the rates are between .45 and .55 per kWh. Basically in the summer between 4 and 9 pm you will roast and won't be able to cook or watch TV. All you can do is sit there in the dark and read a book. Then in the winter between 4 and 9 you have to sit there getting hypothermia. All so you can drive an electric car and save the environment....
How is this supposed to encourage anyone to switch to electric? Yeah, you may be able to save a few bucks on gas but those savings will be more than erased by your regular electric bill skyrocketing. Just this month with a standard plan my electric/natural gas bill is going to be about $400. I mean, seriously, WTF?
The state with the most expensive electricity in the continental US has the nerve to try to convince everyone to switch to electric cars?
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This is the EPA data for mixed driving (fueleconomy.gov). City cycle economy would be better, especially for a boxy looking SUV.
yeah, I asked if it was highway b/c I thought it was worse than my numbers which were a mix of things. it's at least partially (edit: mostly) because he's not using the number on the dash and is instead calculating it himself (a good idea).
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I did not think to calculate for charging loss, so I went online and looked up the losses. It was reported that 12-13% is lost in charging from 240V, and up to 15% at 120V. (Higher loss due to conditioning / maintenance during charging Period. My electrical "SCE" TOU-Prime is .21kw from 9pm-4pm. so YOU made assumptions also to negate my findings (Which apply to me) "Not your averages from Fueleconomy.gov, and an average price you found." in CA the prices go up and down daily and per station can be a $2.00 range. If you use an app for cheep fuel, vs buying fuel in a high end neighborhood at a good station you can find a large range in price. I posted my cost. I am not interested in someone else's Idea of my costs from another state. I drive nice in traffic (Where the Toyota primes do well. I get 40-46mpg when in CA traffic in hybrid mode (Driving an average of 23mph-Traffic-) I drove from Yorba Linda to Santa Monica on battery only 51 miles with 1 mile remaining during traffic. (Your mileage will vary)
My 2018 Prius Prime showed an average of 100.3mpg when it was totaled @ 72K!
I know this is incorrect as when in hybrid only i would get between 52 and 76mpg* (Heavy traffic and maybe a little drafting) Toyota doesn't take into account the electrical usage in the fuel calculation. "I think the posted 133mpge was not combined or acknowledged in the lifetime adv." I think my usage was about 28% electrical and that would be... 72K.28 (20,160 miles getting 133mpgE +/-) and 51,840 miles averaging 56mpg hybrid (Again if you don't think my accomplished mileage doesn't meet the F.E.gov # then TOO BAD! that is how I drive in My Commuting and conditions) my rough lifetime estimate is about 78mpg (Rough +/-) not the 100.3 lifetime
Back to the original post... ok , I missed calculating the charging waste of 15% so i retract my 50% elect. vs Fuel and change it to "I get 185% further on electricity per my location and driving conditions."
Toyota may be lying about the charging received on the battery... I have only seen the what the Toyota app on my 2023 shows.
I know that the average fuel mileage is incorrect. I go by $fuel for the Year + added electrical cost from 9-4pm / miles driven for the Yearly cost. (all this is for fun, as i already purchased the SUV and am trying to see what it costs by the time it is wrecked, stolen, or sold)
does anyone know if charging the battery more slowly could be better for losses? I'm pretty sure it's better for the battery at least.
Charging at 240 volts has fewer losses than charging at 120 volts.
I meant for a given voltage reducing the charging rate. This is a setting the user can change.
I believe that the charge rate settings in the car only apply to 120 volts and are primarily for charging from a circuit that is shared with other devices to prevent tripping of the circuit breaker. I am not sure about different 240 volt charging rates vs. efficiency. My guess is that they are about the same efficiency, although there is probably a very slight decrease in efficiency as the charge time gets longer. This is because there are fans and a 12 volt charger that operate during the charging time.
that was good info on the 240V vs 120V though. thanks!
Even when charging at 6.6kW, that's still relatively slow compared to how quickly the battery cells can comfortably charge/discharge. You'd have to be charging 3 or 4 times faster before you enter the charging rate shown to have a statistically significant effect on battery degradation. And even at that point, battery temperature would have a more significant effect on its health while charging.
In short, there's no effect on battery health between slow 6.6kW charging and really slow 1.4kW charging.
good to know. maybe someday I'll get some 240V out in the garage. I need to do a little research on what this would involve. I also kind of want to get a connection out there to plug in a genny so it might be good to do all of that work at once.
Depends how far your main breaker box is from the garage. In most cases it basically just involves running a new circuit from the breaker box to wherever in the garage you want to put the outlet.
In my case it will mean a few holes in the drywall and about a 30 ft run inside the walls.
But some other cases might be a lot more complicated. Or a lot simpler if your main box is in the garage.
should be pretty straight forward for a pro. my panel is in the basement and very near the garage. probably less than 3' as the crow flies just to get into the garage but my prime is parked on the opposite side of the garage so probably another 20-30' depending on how it gets routed in there.
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This is not correct, I just tried it. I have 16 amp, 240v charger. I just set the charge rate in the car to 8 amps, and that's what I'm getting, 8 amps. "Wide Open", it runs at 15.4 amps. (the charger is limiting it.)
Since I infer from your lengthy post you want to be precise, you seem to have confused what MPGe means. MPG and MPGe can’t be combined together, and are confusing metrics. MPGe is a standard established to compare efficiency of electric vehicles with each other, not ICEs. However, a “MPGe” represents the actual energy in one gallon of gasoline, and has been established as equivalent to 33,7 kWh of electricity. IMO, whoever decided to adopt this EV efficiency metric was a fool, as it confuses almost everyone. So, if your Prius Prime got 133 MPGe, it could travel that far on 33.7 kWh of electricity, not gasoline. Supposedly, the energy expended is equivalent, but the means of propulsion is different. By comparison, the R4P is rated 94 MPGe when it travels in EV mode. The Prius is optimized for economy and efficiency.
But, you cannot blend the total EV and HV miles together and divide by gallons of gas consumed and get an accurate mpg. Your actual mpg in the Prius Prime was close to 56, because that was your HV miles. Efficiency for your EV miles are calculated separately, and in miles/KWh.
so damn! my electricity is more expensive than I thought. when you google rates it seems like you are only given the supply rates. the delivery rates for me take the number from about $0.22/kwh up to about $0.31/kwh. damn it!!!
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Ah, you must live in Massachusetts! WE'RE NUMBER 2! (Hawaii still beats us.)
close. NH. I've looked into the alternative suppliers a little bit but the savings in the short term are pretty low (maybe $20/month?) that the hassle and chances of losing out long term with that locked in rate seems kind of silly.
Your “MPGe” explanation is correct. But just to backup “Beesonmichael”‘s claim, the Prius Prime does return 70+ mpg in HV mode under certain conditions. We see that regularly in the warmer weather in our 2021 PP.
Winter weather knocks it back a bit to the 58-62 range.
This is with the traction battery showing 0%, so it operates a true HV, not an EV.
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