Help with math

[LongIslandY]

hey everyone. I have a 2021 model Y. This might be a rookie issue but :

EPA rating for the 330 miles of range is a 270 wh/mile. With a 75 kw battery, doesnt the math add up to a 278 mile range ?

My car has been giving me approximately 275 wh/mi and I’m getting around 250 miles of range.

I was just expecting to get 330 miles I’m getting the epa estimate of 270 wh/mile.

Can anyone help explain what I’m missing here ?

Thanks

 

[jjrandorin]

Can anyone help explain what I’m missing here ?

Usually, what people miss is that the wh/mi number only counts the energy used while moving. Unless that number you are quoting is "all at once" (which it usually isnt, people are adding it up over a few trips), that also doesnt count energy used when you get started (which is always higher), any pre conditioning, etc.

Im also wondering where the "epa range is 270 wh/mi" comes from. Can you point that out?

 

[jcanoe]

The EPA numbers only work out if you assume somewhere around 234Wh/mi. 270Wh/mi is what many Tesla Model Y owners report in daily use, at least spring, summer and fall. Winter consumption is usually higher, i.e. at least 10 to 20% higher consumption for winter driving. Winter driving can consume as much as 40% more depending on temperature and road conditions.

 

[LongIslandY]

Got it. Thanks

 

[CaseyL]

Im also wondering where the "epa range is 270 wh/mi" comes from. Can you point that out?

It comes from the window sticker. The one that came with our MYLR says 27 KWh per 100 miles which is 270 Wh per mile.

 

[LongIslandY]

It’s just odd to me that tesla puts that 270 wh/mile out there while advertising a range of 330 miles. Should just say 234 wh/mile with that range so everything adds up.

 

[CaseyL]

It’s just odd to me that tesla puts that 270 wh/mile out there while advertising a range of 330 miles. Should just say 234 wh/mile with that range so everything adds up.

An interesting real world factoid is that after 10,000 miles, our MY average consumption is about 270 Wh per mile. This is from a mix of 50-mile commutes mixed with a lot of 600 mile road trips.

 

[Vicj]

Actually, you can see the "rated" line right in your energy consumption screen. It's 250. And as others have pointed out, even 250 won't get you 330 miles. Remember, the EPA allows MATHMATICAL calculations for ev range, not real world testing, like Europe requires. That's why the range figures are lower in Europe.

 

[EVer Hopeful]

It comes from the window sticker. The one that came with our MYLR says 27 KWh per 100 miles which is 270 Wh per mile.

You got a window sticker?

You just made me realise that I didn't. I'm in Texas, so who knows, but I thought that removing one was even worse than removing it from a pillow!

 

[andaconda]

You got a window sticker?

You just made me realise that I didn't. I'm in Texas, so who knows, but I thought that removing one was even worse than removing it from a pillow!

My window sticker was laying on the dash when I picked it up. Every time I get a new car I won't let the dealership remove the window stickers and wait until I get home. They then go in the trunk for the next owner of the car. I figure whom ever purchases the car after me will get a kick out of seeing the original. In fact I have the original documentation from my 1983 VW Pickup.

 

[AlexUA]

hey everyone. I have a 2021 model Y. This might be a rookie issue but :

EPA rating for the 330 miles of range is a 270 wh/mile. With a 75 kw battery, doesnt the math add up to a 278 mile range ?

My car has been giving me approximately 275 wh/mi and I’m getting around 250 miles of range.

I was just expecting to get 330 miles I’m getting the epa estimate of 270 wh/mile.

Can anyone help explain what I’m missing here ?

Thanks

MY 2021 Dual motor likely have 82kWh battery BT42 option. check over Tesla API

 

[Fourdoor]

Actually, you can see the "rated" line right in your energy consumption screen. It's 250. And as others have pointed out, even 250 won't get you 330 miles. Remember, the EPA allows MATHMATICAL calculations for ev range, not real world testing, like Europe requires. That's why the range figures are lower in Europe.

With an 82.x kWh battery pack, 250 wh/mile would get you to the EPA rated range... why are people still using 75 kWh for battery pack size? Yeah, after a year of degradation I will be down to around that... but I figured we are talking new car range aren't we?

Keith

 

[jjrandorin]

Actually, you can see the "rated" line right in your energy consumption screen. It's 250. And as others have pointed out, even 250 won't get you 330 miles. Remember, the EPA allows MATHMATICAL calculations for ev range, not real world testing, like Europe requires. That's why the range figures are lower in Europe.

EV range figures are even less realistic in Europe than they are in the US. Go take a look at WLTP (europe) Rated range for a Model 3. It translates to even farther than the US EPA numbers, but its the same exact car, so even more unrealistic.

 

[jcanoe]

You never have access to the full battery capacity of the vehicle. While the total capacity (when new) now stands at ~82kWh subtract ~4.7kWh for the usable capacity, i.e. approximately ~77.3kWh.

The 2020 Model Y had a total battery capacity of ~77 to 78kWh and a usable capacity of ~74kWh. At least that is what the document that Tesla provided with my 2020 LRMY (This documentation (a single piece of paper) was provided for use with a Maryland rebate. The battery capacity stated on the document is 74kWh.) There is also a label under the hood (located beneath the removable cover). Tesla no longer includes this label.

74kWh/.234kWh/mi = 316.2 miles (316 miles was the original stated EPA combined City/Highway figure before it was restated to be 326 miles, now 330 miles.) 77.3kWh/.234kWh/mi = 330.3 miles.

BTW, 82kWh/.234kWh/mi = 350.4 miles. If Tesla could claim an EPA estimated combined City/Highway range of 350 miles they would but they don't.

 

[roblab]

You mean you worry about how many miles you will get on a "tank"? Why? Did you ever stress about how many miles you'd get on a tank of gas? And your gas car had no means of "charging up" in the garage overnight, for a fraction of the cost of going to the pump, never mind that people can put up solar panels on their roof and collect their own power. Most of us have at least 110 available, and often we can get a 220 outlet installed (I installed mine myself}. When I had a business, I installed a gas pump (25 vehicles), and THAT was a major undertaking.

Unless you have issues with getting your car charged, worrying about how many miles you get on a charge is wasted energy. Your usage can vary dramatically based on weather, elevation, speed, driving habits, etc., etc. Just quit worrying and enjoy your car.

 

[Rocky_H]

Can anyone help explain what I’m missing here ?

As @jjrandorin was mentioning, the usage on the screens won't include some small idle time usage and very large idle uses like the car using Sentry mode and things like that. It only cumulatively counts up usage totals on that screen while in a drive gear.

It comes from the window sticker. The one that came with our MYLR says 27 KWh per 100 miles which is 270 Wh per mile.

It’s just odd to me that tesla puts that 270 wh/mile out there while advertising a range of 330 miles. Should just say 234 wh/mile with that range so everything adds up.

Oh, this is from two different kinds of measurements being done. When people here are usually talking about their Wh per mile figures, they mean in the car, which is just from energy in the battery to the wheels. But the EPA number on the window stickers is from their measurement of the total amount of energy used from the circuit in the wall, including the losses in the charging process. So that is going to have some extra losses from the charging process and also includes using every last drop of energy down to below the 0 reading on the display, until the car completely stops. So that outside EPA figure is a little off versus what people are saying with driving Wh per mile figures.

Actually, you can see the "rated" line right in your energy consumption screen. It's 250.

That has never been exact and wasn't really designed to be. The Model S always used to have that line marked "rated" at the nice round number "300". But it was always on 300 across all versions of Model S: Performance, non-performance, rear wheel, dual motor, Ludicrous, etc. Those all have slightly different efficiency constants, but they don't show those little distinctions on precisely where they mark that "rated" line on the display. That's a little more vague on a round number like 250 or 300.

 

[Exelion]

The whole range thing all comes from Tesla's website. If that same website posted something like this (note the range figure):

There would be a whole lot less complaining, whining, anger etc. about how people got cheated out of a car that should have X miles posted instead of Y actual mileage gotten. But I think the real reason why Tesla will never post such (accurate) numbers is because they'd lose a lot of sales that way. Yes, I do understand that 180, 265, 300, 330, 365 are all ranges that are way over I need out of a typical 20 miles to work every day, and maybe 100 on weekends. Thankfully I have the Long Range and its gotten about 250-270 realistic miles and so that's fine. I also get that if I granny-gassed the pedal I can (maybe) get the 3XX miles tesla site says I would get. Consider the following car, is $45,000 an attractive price for a car with 170 miles of range?

 

[Mrbrock]

EPA ratings are done at constant speeds in warehouses on dynos. No wind resistance. Then a multiplier is applied to get the posted number. There are many cycles and ways to game this multiplier. Tesla seems to be at the high end of the gaming, other manufacturers less so (see Porsche).

The Secret Adjustment Factor Tesla Uses to Get Its Big EPA Range Numbers

How Tesla puts distance between itself and the competition while still playing by the EPA's rules.

www.caranddriver.com

 

[Vicj]

This isn't quite true. EPA ratings are completely mathematical. There is no actual testing of any sort done. The math can be fudged. This is how Tesla gets away with Range figures that, uh, aren't quite true. Edmund's did an interesting test a year or so ago. They did tests on every EV out at the time. EVERY manufacturer got MORE range in than advertised...except Tesla. They were the only one that consistently got less . I knew this when I bought mine, but thought that the Supercharger network was a big selling point. I've used it...hmmmm... once.

 

[Mrbrock]

They actually do test. They have to.

https://dis.epa.gov/otaqpub/display_file.jsp?docid=54293&flag=1

Start on page 40. You will see all the tests they carry out to submit the range before the adjustment factor.