EVs Fall Short of EPA Estimates by a Much Larger Margin Than ICE in Real-World Highway Testing

No surprises here, but useful data and insights as to why:

• On Car and Driver's 75-mph highway test, more than 350 internal-combustion vehicles averaged 4.0 percent better fuel economy than what was stated on their labels. But the average range for an EV was 12.5 percent worse than the price sticker numbers.
• While separate city and highway range figures are computed behind closed doors, only a combined number is presented to consumers. The combined rating is weighted 55 percent in favor of the city figure, where EVs typically perform better. This inflates the range estimates, making it harder to match in real-world highway driving. The paper proposes publishing both city and highway range figures—as with fuel-economy estimates for gas-powered vehicles—to give shoppers a more holistic sense of a vehicle's abilities.

EVs Fall Short of EPA Estimates by a Much Larger Margin Than Gas Cars in Our Real-World Highway Testing

Gas-powered cars often match or exceed EPA highway fuel economy numbers. A new paper using data from C/D's highway tests shows EVs are far less likely to do so.

www.caranddriver.com

Comparison of On-Road Highway Fuel Economy and All-Electric Range to Label Values: Are the Current Label Procedures Appropriate for Battery Electric Vehicles?

As consumers transition from internal combustion engine (ICE)-powered vehicles to battery electric vehicles (BEV), they will expect the same fuel economy label-to-on-road correlation. Current labeling procedures for BEVs allow a 0.7 or higher multiplier to be applied to the unadjusted fuel economy a

www.sae.org

"Chevy Bolt EV sulla rampa di lancio!" by automobileitalia is licensed under CC BY 2.0.
Admin note: Image added for Blog Feed thumbnail

 

[XPsionic]

The EPA displays a highway/city efficiency rating for EVs, but it's in a rather useless metric called mpge.

Not only is the highway epa rating in a useless unit, it's also not consistent with what most people (like car and driver) considers highway driving.

The EPA really ought to update how they test and what they display so consumers could be better informed.

 

[ItsNotAboutTheMoney]

Fixed speed tests would help. A 75mph is pretty much useless for me, since my regular Interstate speeds are up 70, but 45 to 70 in 5s would be useful.

 

[NeverGoingBack]

It’s really just a way to compare different models if range or fuel economy is an important buying criterion. I’ve never found EPA estimates (ICE or EV) useful for anything else. Never have expected or experienced performance to match estimates.

 

[sightman]

The EPA displays a highway/city efficiency rating for EVs, but it's in a rather useless metric called mpge.

Not only is the highway epa rating in a useless unit, it's also not consistent with what most people (like car and driver) considers highway driving.

The EPA really ought to update how they test and what they display so consumers could be better informed.

I believe they have. But the epa does not factor in hvac which has a greater impact on EVs.

The epa has a calculator you can play with since EVs rely on a degree of regen which you don’t get on a highway drive.

 

[blackT3$!@]

Imagine the surprise to new EV owners in colder climates that as soon as the temperature drops, so does an EV’s range. If you had a regular commute that left you with 10% battery remaining when arriving back home, in the winter you need to find a charging stop on your return trip.

 

[Leafdriver333]

I was surprised the first time when i went 75-80mph during a trip to Seattle. Surprised, Panicked, disappointed, and came to an understanding and agreement.
No more. I drive ICE for trips.
But it is an amazing in town car, no doubt.

 

[SageBrush]

This inflates the range estimates, making it harder to match in real-world highway driving. The paper proposes publishing both city and highway range figures—as with fuel-economy estimates for gas-powered vehicles—to give shoppers a more holistic sense of a vehicle's abilities.

The article is BS, compounded by arithmetic illiteracy
City and Highway tests are published as MPGe
The 'penalty' as it were is ~ MPGe of highway/combined. The 55/45 city/highway weighting does not have a lot of effect, as can be seen is this example:



Combined is 132 MPGe using 55/45 weighting,
While 50/50 weighting results in 2/((1/138+1/126)) = 131.6

The larger the difference between city and highway, the more the combined result will poorly represent the highway range.
Who wudda thunk ?!?

Answer: use the highway MPGe. Brilliant !!

The EPA displays a highway/city efficiency rating for EVs, but it's in a rather useless metric called mpge.

Not useless at all, although I agree that it is clumsy.
An interesting question to me would be comparing EV/ICE to EPA highway MPGe in highway driving at 70 mph. Would the EVs show a larger discrepancy ? I think so, of around 5%

 

[Don.Church]

Why couldn’t the EPA create a whole new metric, just for EV’s? Something like kWH per mile for city/highway. Mpge is useless to me.

 

[Zythryn]

Why couldn’t the EPA create a whole new metric, just for EV’s? Something like kWH per mile for city/highway. Mpge is useless to me.

How about kWh/100 miles?

Learn More About the Fuel Economy Label for Electric Vehicles

Learn More About the Fuel Economy Label for Electric Vehicles

www.fueleconomy.gov

It is number 5 on the graphic. Right next to the city and highway ratings.

The MPGe is done so people can easily compare the relative efficiency of gas vehicles and EVs.

 

[ItsNotAboutTheMoney]

Imagine the surprise to new EV owners in colder climates that as soon as the temperature drops, so does an EV’s range. If you had a regular commute that left you with 10% battery remaining when arriving back home, in the winter you need to find a charging stop on your return trip.

I'd be surprised if a high proportion of EV owners were surprised. People are generally well aware that there's a lot of cold-weather range loss. It's one of the negatives that general media will mention.

But it's nuanced enough that it's difficult to know exactly how much range is affected. Just having a conservative view of range is enough to make a decision.

I pity anybody who is using 90% of range to commute.

 

[Theone8181]

I'd be surprised if a high proportion of EV owners were surprised. People are generally well aware that there's a lot of cold-weather range loss. It's one of the negatives that general media will mention.

But it's nuanced enough that it's difficult to know exactly how much range is affected. Just having a conservative view of range is enough to make a decision.

I pity anybody who is using 90% of range to commute.

If it was a leaf then fair enough, but something like a tesla (even a base SR), I'd just move closer to work. That would be a 3 hour commute each way surely?

 

[ATPMSD]

This statement pretty much sums it up for me:

“A range discrepancy between EVs from different companies might not be as extreme as the numbers would suggest. "400 miles of stated range for a Tesla and 300 miles for a Porsche is pretty much the same number at real highway speeds,"

 

[SabrToothSqrl]

Imagine the surprise to new EV owners in colder climates that as soon as the temperature drops, so does an EV’s range. If you had a regular commute that left you with 10% battery remaining when arriving back home, in the winter you need to find a charging stop on your return trip.

When I bought my first Model S in 2015, the car said it had a 250+ mile charge. Easily make it back from NJ to PA. NOPE. Not even close. Luckily there was a supercharger along the way, but it sure was scary back then. I think there were like 10 super chargers in the US, and zero in dash charging info.

 

[BeeBee]

We’ve had our MY for 3 years and 30K miles. It’s rated at 4.2 mi/kW. Lifetime so far I’ve averaged 3.6 (15% less than rated). At a constant 50 MPH I can get 4+. Around town I often reach 5+. Any speed north of 60 MPH and the efficiency drops drastically. But I’m experiencing similar results with my ICE Jeep Grand Cherokee with 3.5L V-6 which is rated at 26 MPG highway and 22 combined. Real world we get 22 highway, 20 combined and 17-19 in the winter. Some of those are 15% less than rated. The bottom line is that our EV gets 120+ MPGe vs the Jeep’s 20 MPG. Granted the EV’s equivalent “gallon” of energy is in the $4-$5 range. But we are still way ahead on efficiency along with all the other EV benefits like amazing 0-60 times… hmm maybe that’s why my efficiency is so low

 

[RichAZ/CapeCod]

I give talks on EVs regularly (several times a year). In my book on EVs I let folks know they should figure on 70% of the rated and shown range of whatever EV they are interested in purchasing as the practical distance that vehicle will travel:

From the chapter Distance Travel by EV?~Read This First!!

"Let me start off by suggesting that whatever the EPA rating of range is shown for your new EV, figure you’re good for around 70% of that distance with a 100% SoC start while driving at highway speeds. It’s not a conspiracy. The EPA shows a blended range of city and highway travel. Most (not all) EVs won’t get you the full distance shown when you travel at highway speeds. Sorry about that."

Rich

 

[BeeBee]

I give talks on EVs regularly (several times a year). In my book on EVs I let folks know they should figure on 70% of the rated and shown range of whatever EV they are interested in purchasing as the practical distance that vehicle will travel:

From the chapter Distance Travel by EV?~Read This First!!

"Let me start off by suggesting that whatever the EPA rating of range is shown for your new EV, figure you’re good for around 70% of that distance with a 100% SoC start while driving at highway speeds. It’s not a conspiracy. The EPA shows a blended range of city and highway travel. Most (not all) EVs won’t get you the full distance shown when you travel at highway speeds. Sorry about that."

Rich

Here’s something else to consider. You really can’t use the last 10% of the battery or you might get stranded and need a tow. So on our EV that’s 30 miles of the advertised range that I can't use. Then add to that all the other factors that lead to lower efficiency like weather, speed and terrain. That’s why I get about 25% less range than advertised. ICE cars have similar range loses but manufacturers figured out a long time ago that by installing larger gas tanks they can advertise very attractive range estimates. Like my Jeep that is rated at 500+ miles which in real life is more like 400 miles. EV manufacturers can’t readily do this because the battery is one of the most expensive and heaviest parts of the car. Sure you can pay $100K for an EV that’s rated at 400+ miles range but they won’t sell very many of them because the average person can’t afford it.

 

[RichAZ/CapeCod]

Here’s something else to consider. You really can’t use the last 10% of the battery or you might get stranded and need a tow. So on our EV that’s 30 miles of the advertised range that I can't use. Then add to that all the other factors that lead to lower efficiency like weather, speed and terrain. ...

Yup. I go through a whole song and dance in the book on what impacts EV range, the most thoughtful way to highway travel in your EV, etc.

Rich

 

[STS-134]

Why couldn’t the EPA create a whole new metric, just for EV’s? Something like kWH per mile for city/highway. Mpge is useless to me.

Just have all manufacturers do a plot of range vs. speed, from about 35 to 120 mph, so that:
1. Everyone can see how speed affects range
2. Companies that make "compliance cars" that are very efficient at low speeds/during testing but become ridiculously inefficient at higher speeds due to use of permanent magnet motors with too much back EMF will be exposed, because you'll see their range drop off a steep cliff at higher speeds

 

[Sklith]

I always try to arrive at DCFC locations at 5% or less since that's where you'll be charging the fastest.