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Actual rated wh/mi

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Now the bottom line. Unless you charge at work or some other location where someone else pays for the electricity you are probably paying about $5 or a little more for a gallon equivalent (33.7kW) of electricity when you charge at home (Supercharger costs are even higher.) If gas costs you $3.20 per gallon and you achieve (best case) 56 MPG in your Prius your cost per mile (just for gas) is 5.7 cents per mile. The cost per mile of driving the Tesla Model Y would be $5/125MPGe or 4 cents per mile. Many conventional (non-hybrid) internal combustion engine (ICE) vehicles such as trucks and SUVs never get anywhere near 30 MPG let alone 56 MPG, typically not much over 20 MPG. At $3.20 per gallon for gas driving a conventional ICE vehicle that achieves 22 MPG would cost 14.5 cents per mile.
That’s the bottom line for us - we also have a Honda Odyssey. It’s a great car but gets about 20 MPG. At $3.20 per gallon that’s $0.16/mile in fuel costs compared to $0.015 ~ $0.03 per mile for my model Y.
 
Now the bottom line. Unless you charge at work or some other location where someone else pays for the electricity you are probably paying about $5 or a little more for a gallon equivalent (33.7kW) of electricity when you charge at home (Supercharger costs are even higher.) If gas costs you $3.20 per gallon and you achieve (best case) 56 MPG in your Prius your cost per mile (just for gas) is 5.7 cents per mile. The cost per mile of driving the Tesla Model Y would be $5/125MPGe or 4 cents per mile. Many conventional (non-hybrid) internal combustion engine (ICE) vehicles such as trucks and SUVs never get anywhere near 30 MPG let alone 56 MPG, typically not much over 20 MPG. At $3.20 per gallon for gas driving a conventional ICE vehicle that achieves 22 MPG would cost 14.5 cents per mile.
I assume you meant $0.05 not $5? Either way, that’s a lot more efficient than I expected. Thank you all for helping me make sense out of that word salad on my screen!
 
I assume you meant $0.05 not $5? Either way, that’s a lot more efficient than I expected. Thank you all for helping me make sense out of that word salad on my screen!
The cost of ~34 kWh (the equivalent electricity energy stored in 1 gallon of gas), consuming that amount of electricity can exceed $5 in many places. The cost per individual kWh may be closer to $0.05, probably $0.07 or a bit more per kWh. When you add the power distribution cost to the power generation cost ($0.07) you get a total cost per kWh of $0.15, in many places even more.

A gallon of gas equivalent (in kWh) can be expensive unless you have a solar panel system. If you can travel 4 or 5 times further on the same amount of energy as an ICE vehicle can travel on a gallon of gas you are still way ahead in terms of your cost per mile. $5.00 per gallon equivalent (for electricity) divided by 125 miles = $0.04 per mile for the Tesla Model Y (estimated); $3.20 per gallon for gas divided by 22 miles per gallon = $0.15. The cost per mile of driving the gas vehicle is almost 4 time more.
 
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The cost of ~34 kWh (the equivalent electricity energy stored in 1 gallon of gas), consuming that amount of electricity can exceed $5 in many places. The cost per individual kWh may be closer to $0.05, probably $0.07 or a bit more per kWh. When you add the power distribution cost to the power generation cost ($0.07) you get a total cost per kWh of $0.15, in many places even more.

A gallon of gas equivalent (in kWh) can be expensive unless you have a solar panel system. If you can travel 4 or 5 times further on the same amount of energy as an ICE vehicle can travel on a gallon of gas you are still way ahead in terms of your cost per mile. $5.00 per gallon equivalent (for electricity) divided by 125 miles = $0.04 per mile for the Tesla Model Y (estimated); $3.20 per gallon for gas divided by 22 miles per gallon = $0.15. The cost per mile of driving the gas vehicle is almost 4 time more.
The unfortunate thing is that the cheapest rate for Southern California Edison EV owners is $15/kWh off-peak plus the usual service fees. Gas is getting close to $5.00 per gallon.
 
The unfortunate thing is that the cheapest rate for Southern California Edison EV owners is $15/kWh off-peak plus the usual service fees. Gas is getting close to $5.00 per gallon.
Do you mean $0.15/kWh? I'm in So Cal Orange County and Edison charges us $0.22/kWh and $0.32/kWh (we're in tier 2, not Tier 1). Tier 1 costs $0.16/kWhr.
 
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I am having a really hard time relating wh/mi to some sort of efficiency rating. Basically I have no idea if I’m being efficient and by how much. Currently my MY shows an average of 256 wh/mi, it’s a 2022, if that matters. How does that relate to MPG or MPGe?

Off the bat yes 256wh/mi is pretty efficient i’d say over 315wh/mi+(People will argue on this one) is on the low end of efficient on the MY but still can get like 200miles give or take on a full charge


To add on the rest convo of money saved spent etc.

My personal take, my previous 18 accord(2.0 engine) got about 21-24mpg average i filled up at 30-40$ a year ago weekly, it would probably be more nowadays but that was about 120-160$ a month give or take

I charge MY about 1 a week(35-40% to 90%) with an extra charge squeezed in there so lets say 5 times a month i do it at off peak 8 cents(EP Electric) per Kw

Since im just gonna take a wild guess here i never charge the max 77 usable kw of my battery im gonna go on the high end for purposes and say i charge about 50kw but its really usually less look at the pic for reference

0.08cents x 50kw = 4 dollarz
4 dollars x 5 times a month = 20 dollarz a month

Sure u can add gas surcharge and all that garbage on the electric bill that i paid for before the car anyways

Huge savings for me personally

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Yes, I meant $.15. The December rates are Tier 1=$.16, Tier 2=$.23. The TOU-D-Prime from 9:00 PM to 4:00 PM is $.19 and between 4:00 PM to 9:00 PM is $.48. TOU-D-Prime is for EV owners.
The EV rate there is a rip
Off. PGE has a similar plan in Bay Area and if you do your math, you’ll find it’s a much higher annual bill.

To OP I’m averaging just over 300wh/mi but I drive faster than average as it is so effortless. Highway speeds kill me the most. 85-90mph uses like 360-400.
 
Depends on the state and implementation. In MD, if you're willing to take the privacy risk, you get the EV rate on only your car's charging energy. You need to give a 3rd party site a Tesla login to do that if you're using the Tesla wall charger (or any charger than the couple they can directly log into). Power is discounted quite a bit off peak. That's 11:00 am to 5:00 pm, and 9:00 pm through 7:00 am in the winter. 8:00 pm to 10:00 am in the summer.

Regular power: $0.0833 + delivery
Summer:
EV peak: $0.13597 + delivery
EV off peak: $0.03752
Winter:
EV peak: $0.14676
EV off peak: $0.04457

Delivery is: $0.04106 on top of those rates.

All of my charging is off peak, so I pay:
Summer: $0.07858/kWh
Winter: $0.08563/kWh
 
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Yes, I meant $.15. The December rates are Tier 1=$.16, Tier 2=$.23. The TOU-D-Prime from 9:00 PM to 4:00 PM is $.19 and between 4:00 PM to 9:00 PM is $.48. TOU-D-Prime is for EV owners.
Here is an attached screenshot from the SCE website for December billing period. Its actually higher than our November billing period of 0.22 and 0.32/kWhr. I'm sure it depends on your municipality in Orange County. Also, we're not on a TOU plan because we are home a lot during the day/during peak usage fees so it doesn't make sense for us.
 

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Yes that is basically true. As mentioned above.

Note that for “reasons” the rated line is 5Wh/mi higher than the actual charging constant.

And because of the buffer you have to be 4.5% lower than that constant for mile-for-mile rolloff.

And because of heat losses you have to be about 1% lower than that as measured on the trip meter.

So for the non-P Model Y take 77.8kWh or so and divide by the rated miles on the Tesla website (whatever the true adjusted max rated range is for the vehicle). That will give you the charging constant.

When the vehicle is new and the energy exceeds the degradation threshold, you’ll be able to use a little more per mile and still achieve parity, since the rated mile energy content will be slightly inflated. (For example you might have 78.5kWh at 100% rather than 77.8kWh, in which case your rated miles will have 1% more energy than later in life, to hide initial capacity loss.)

So for Model Y with 77.8kWh battery with rated range of 326mi initially the constant is about 239Wh/mi. Line on energy screen is probably about 244Wh/mi.

And if you show some rated range loss, you need to get about 226Wh/mi on the trip meter for mile-for-rated-mile “parity.”
confirmed my line is exactly 244 ... 2021 LR 11/1 Delivery

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AHA! thanks for examples and info. My Lexus 014 RX hybrid gets 30-32mpg @ $4.90/gal. My 7 mo old MY calculates out to 125mpg. But given my electricity costs of $.32/KwH(home charging 110A circuit) I figure it’s the equivalent of a 60mpg car so twice as good as Lexus. Hawaii kind of expensive.
 
AHA! thanks for examples and info. My Lexus 014 RX hybrid gets 30-32mpg @ $4.90/gal. My 7 mo old MY calculates out to 125mpg. But given my electricity costs of $.32/KwH(home charging 110A circuit) I figure it’s the equivalent of a 60mpg car so twice as good as Lexus. Hawaii kind of expensive.
Don't forget about the benefit of being able to charge at home. You probably have a preferred gas station but it may not be all that convenient or safe.
 
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Here is more B.S.

Originally the data Tesla submitted to the EPA for the Long Range Model Y resulted in an EPA range estimate of 316 miles. This was with the usable battery capacity of somewhere between 72kWh and 75kWh depending on where you shop your B.S. (The total battery capacity was somewhere around 77 to 78kWh.)

My Long Range Model Y came with a sheet of paper indicating that the battery pack in my vehicle had a capacity of 74kWh (At the time I purchased my Model Y (June 2020) the State of Maryland had a sales tax rebate program that was keyed to the size of the battery, so Tesla should not have B.S'd around this number.) 74kWh/316miles = 234Wh/mi. Tesla later restated the estimated EPA range of the Long Range Model Y as 326 miles. 74kWh/326mi = 226Wh/mi.

Your results (279Wh/mi) X 79% = 220Wh/mi which is close to the Wh/mile number for the restated range (226Wh/mi). Early on some had stated that the actual usable capacity of the battery in the Model Y was closer to 72kWh so then the Wh/mi number would be right at 220Wh/mi. So somewhere in there lies the true EPA combined City/Highway Wh/mi estimate and the reason your results are 79% of the rated efficiency.

If there is a B.S. number it is 220 Wh/mi. 220Wh/mi / 79% = 278.5 Wh/mi (almost exactly your result.) No result outside of a Dyno test is ever going to achieve 220Wh/mi combined city and highway in a Tesla Model Y.

I have an August 2020 Model Y long range and often get 220Wh/mi combined if I’m driving genherly in good weather. Todays round trip half highway was 214. Though I do a lot of road trips all highway and drive pretty fast, so my lifetime is 256.