The Case For The E-REV

APR 21 2016 BY MATT DOUDE 211

The Most Famous E-REV - 2017 Chevrolet Volt

The Most Famous E-REV – 2017 Chevrolet Volt

Specific Energy (Wh/kg)

Specific Energy (Wh/kg)


The extended-range electric vehicle is thought of by many as a stepping stone on the technological highway to battery electric vehicles.  The E-REV, however, deserves a second look as a viable long-term technology.

Batteries are heavy.  Everyone knows that batteries are heavy, but check out the chart to see exactly how true this is as compared to conventional fuels like gasoline.

In fact, it’s hard to imagine a scenario where electrochemical energy storage ever matches the specific energy or energy density of refined liquid hydrocarbons.

Take the relatively low specific energy of batteries and combine it with the fact that most people drive 40 miles or less every day, and you get a bunch of EV drivers dragging around thousands of pounds of batteries that are usually unnecessary.

How does that translate into vehicle efficiency?  The Tesla Model S has a rating of 38 kWh/100 miles, while its EREV cousins – Fusion Energy, Volt, and i3 have ratings of 37 kWh/100 miles, 31 kWh/100 miles, and 29 kWh/100 miles, respectively.  In fact, the Model S has one of the highest electric energy usage rates of all the vehicles surveyed on InsideEVs monthly sales scorecard.

The weight difference is not all in the wheels

The weight difference is not all in the wheels

The point here is not to pick on Tesla, and it is certainly true that vehicle energy consumption is influenced by a lot more than just battery mass.  However, it is worth considering that, for many people, Ford’s Kevin Layden got it right:

A Chevrolet Bolt EV battery pack, far right, is compared to battery packs from, left to right, a first generation Volt, a second generation Volt, and a Spark EV in General Motors Global Battery Systems Laboratory at the GM Technical Center in Warren, Michigan, Tuesday, April 5, 2016. (Photo by Jeffrey Sauger for General Motors)

A Chevrolet Bolt EV battery pack, far right, is compared to battery packs from, left to right, a first generation Volt, a second generation Volt, and a Spark EV (Photo by Jeffrey Sauger for General Motors)

“I think right now with the launch of the Focus Electric at 100 miles, it is going to satisfy a big chunk of the population.” 

General Motors would slightly disagree, as they would rather sell you 53 miles of electric range, followed by several hundred miles of gasoline range.  Both have sound logical background, but the Volt does offer more flexibility in total range.  The Gen 2 Volt will also likely log nearly as many all-electric miles as a 100-mile Focus would, extrapolating the results of this study from Idaho National Lab.

The future is likely to support a number of different transportation technologies for decades to come.  For many, the E-REV will be simply a more economical and efficient powertrain.

About the author: Matthew Doude is program manager for powertrain engineering and business development officer at the Center for Advanced Vehicular Systems, part of Mississippi State University.

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211 Comments on "The Case For The E-REV"

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Nothing wrong with the Volt 2.0, it’d be in my driveway right now except for car things like:
-Rear Seat Headroom
-Rear Seat Legroom
-No Wagon Model.

If I get divorced and lose custody of the kids, I’ll get a Volt, when I don’t need rear seat room.

I just cannot understand how GM doesn’t address this.
It’s far cheaper to roll out a variant, then to design a completely new car.


I am in the same situation with the Volt. It is just too small in the back seat area. I don’t have kids but I have adult friends and clients sitting in the back of my Volt every week. I am about to return my leased 2013 Volt and if it wasn’t for the tiny back seats I would be buying another Volt.
750 mpg plus about $18 of electricity a month is nice but eating the steering wheel so my passengers can breathe is not optimal.
Not sure what I will buy.


Possibilities… Pacifica Hybrid, Outlander PHEV, Fusion Energy?

(not sure when the first 2 arrive)


The Hyundai Sonata plugin is pretty reasonable as well. It has nearly 30 miles of electric range.


I have driven the Ford Fusion Energi twice, and I like it but I want more AER.
The Subaru is a possibility but I lose my Volt lease in June. The Hyundai looks ok but I really would like to buy an American car.
I can’t see myself in the Pacifica.
I may see if I can tack another month or two on it, because work has been so busy lately I haven’t really been looking as diligently as I should.


3rd year driving an Fusion Energi, lifetime so far 42,000 miles, 87.7% electric, 100.8 MPGe, and ave 2,976 miles per tank.

I live 19 miles from work and can charge there, which makes all the difference.


Amen- I’m on the 5th year of driving a Volt (last year of my lease) and would LOVE a CUV with the Voltec powertrain. Nothing at all wrong with my Volt expect what you mentioned above. Love everything else about it otherwise.

Maybe they need to get the Bolt out first. I’m hoping we see GM brand Voltec based CUV at the NAIAS in January.


“I’m hoping we see GM brand Voltec based CUV at the NAIAS in January.”

My Christmas wish!!!!!!!


This is the thing with Tesla.
It designs cars with No Flaws, from the ground up, purpose built. Building on the Cruz platform was a mistake.

The Cruz’s role is inexpensive compact car that does not steal sales from the Malibu.

So you have a Volt that can’t steal sales from a Malibu either, and therefore you’ve got low sales, while Tesla has 400,000 pre orders of the Model 3.


“The Cruz’s role is inexpensive compact car that does not steal sales from the Malibu.”

Why says a Malibu PHEV would only steal Malibu sales?

Volt has 70% conquest rate. A Malibu PHEV with similar conquest rate would have mean more conquest sales from competitors such as Accord, Camry and Fusion. (two of them have PHEV version)


Yeah, I just don’t get it. Why won’t GM put that Voltec drivetrain into more body styles?

OK, they did put it in the ELR. But that was a bad idea. People just viewed it as a gussied up Volt . . . and that was correct no matter how much GM tried to deny it. And besides, your Fox News watching Grandpa doesn’t want a plug-in.

They gotta put the Voltec drivetrain in a CUV, SUV, minivan, etc.


It’s always the same answer… because they DON’T want to go electric, like all other established car makers. They make believe and they comply.period.

The real change is coming from new companies.

Eric Cote

That is not GM’s answer, that is only what the nay-sayers like to state.

In reality, I suspect they are very likely to put it into a CUV platform once the batteries allow for 40 miles all electric range before using gasoline, in a heavier CUV platform.

Let’s not forget the Voltec MPV5 concept. GM certainly has been thinking about that segment, they are just waiting for the batteries to support it.

Unlike every other manufacturer, GM believes in a long-range EREV, i.e. full electric 40+ miles before using gas. I applaud them for that.


GM is way ahead of others, especially the Germans, but RexxSee is right. Volt is going on 6-7 years old, and still no decent sized installation? BTW, the Cadillac CT6 is to be rated at 37 miles (close to your 40). But there again, what kind of offering is this expensive, non-ground up, Chinese made alternative to the Volt going to amount to? Will Cadillac’s DeNysschen import one, or two?


“TW, the Cadillac CT6 is to be rated at 37 miles (close to your 40). But there again, what kind of offering is this expensive, non-ground up, Chinese made alternative to the Volt going to amount to”

CT6 is a full size sedan. So, if you put the same thing in a bigger/heavier car, it will get less range. That is a given.

So, I don’t see how you can make that complain.

That is still way ahead of just about everyone in the game…


That chart is misleading. You really need to compare the specific energy compared to the weight of fuel PLUS the weight of the engine, exhaust, radiator, etc. versus the electric motor, charger, etc. The electric motor drivetrain is far lighter than the equivalent gas powered engine.


Agreed. Also the engine efficiency needs to be considered. Just because gasoline has a lot of energy, a lot of it goes straight to heat waste.

For the fair comparison you do need to consider the heat waste in EVs too but it is a smaller percentage.


Indeed. As only only about 40% (max) of the stored chemical energy in gasoline can be converted to useful work (i.e motion) in a car. The rest of the energy is wasted as heat out the exhaust and radiator/engine block. So to comparing specific energy per energy source is extremely misleading.


Consider also the vibration, friction and unburned expelled gases losses.

The ICE in cars is 15-% efficient vs +90% for the EV.



mr. M

double that number for european cars.


Okay, 180% for European EVs.


I find the conclusions of the article not broadly focused enough to indicate the true superiority of the bev over any exiting way to power a vehicle.
1. Bottom line it’s magnitudes better in efficiency.
2. Hundreds of thousands of places to charge, thousands fewer moving parts.
3. 97% customer satisfaction ratings for the best of them.
4. 2-2.5 times the storage space.

The counter argument made against this overwhelming example of superiority, theory and actual, gives one pause to wonder how a classically trained engineer could arrive any other conclusion other than the bev will be the primary mode of vehicular transportation in the coming decades.

Oh course he does have a dog in the hunt.
Just the musings of common layman with no technical training. So what do I know?
One thing. War, what on Earth is it good for?
Absolutely nothin’ just like this article.

Tony Williams

Who knew that the answer was…. drum roll… gasoline !!!


I’ll stick with clean electricity, thank you very much.


+1 Tony.

I am a huge believer in PHEVs and “EREVs” and I love my Chevy Volts. However, as soon as there are dependable fast charging networks in place there will not be a need for hybrids.

Thank you for your efforts to install fast chargers and otherwise accelerate the electrification of the automobile via QuickChargePower dot com.



My problem with the Volt is that while most miles are pure electric, they carry around a very heavy drive train while they do it.

In the ideal solution, the rarely used should be as light as possible. This leads to serial hybrid solution. Perhaps even better would be a portable/removable range extender.

David Murray

And how much extra batteries is a Tesla carrying around that it doesn’t need every day? I guarantee the weight and cost of those extra batteries is more than the ICE in the Volt.


With the energy density of batteries improving by more than 10% per year, one of those is going to get much lighter, and the other isn’t.

We might see 300 pound battery packs quite soon. As the packs get smaller, air cooling will become more practical, leading to another weight reduction. Your engine + radiator + exhaust + transmission will still be over 600 lbs because the companies making EREVs are trying to use conventional piston engines compatible with their assembly lines.

Now if they come up with an air-cooled generator with no transmission, it’s a lot more interesting. There are people out there who modify turbocharger units into actual gas turbines to fly models.

“With the energy density of batteries improving by more than 10% per year, one of those is going to get much lighter, and the other isn’t.” Why can’t they? With smaller weight, the E part of the EREV will be lighter so its REx will get smaller as well. You can also use a different type of REx. “We might see 300 pound battery packs quite soon.” For 100kWh? How soon? “As the packs get smaller, air cooling will become more practical, leading to another weight reduction. ” Why is that? Higher energy density potentially means you will have less area to dissipate more heat. So, the larger capacity of the liquid transfer might be a bigger requirement. The only thing it will help is if the C discharging rate is lower which reduces heat generation. But until we know the chemistry, it is still an unknown. “Your engine + radiator + exhaust + transmission will still be over 600 lbs because the companies making EREVs are trying to use conventional piston engines compatible with their assembly lines.” Transmission? What transmission. EREV such as i3REx doesn’t have one. Volt’s transmission have either 1 or 2 planetary gearset which is about… Read more »

David Murray asked:

“And how much extra batteries is a Tesla carrying around that it doesn’t need every day?”

None whatsoever. The idea that any BEV in production today has more batteries than the driver/owner needs, is a bad meme which needs to be strangled.

Some advantages of a larger battery pack:

1. Longer range, and thus greater flexibility in using the car

2. Fewer charge/discharge cycles, and thus longer battery life

3. Better resale value of the new car because of #2

4. The potential for faster recharging. Not only does this make road trips faster, it also again increases the flexibility of the car… because you might be able to drive it again later the same evening after a short recharge in your garage.

So let us please stop describing a high capacity battery pack in a BEV as something the car “doesn’t need”.

Eric Cote
Somewhat ironically, all four points you made could also be argued in favor of an EREV concept like the Volt. 1. Longer range, and thus greater flexibility in using the car (engine after 50 miles when the battery is depleted gives you unlimited range). 2. Fewer charge/discharge cycles, and thus longer battery life (engine comes on after 50 miles for those longer trips, battery is only cycled once for a 1,000 mile trip just like it is cycled once for a 50 mile trip.) 3. Better resale value of the new car because of #2 4. The potential for faster recharging. Not only does this make road trips faster, it also again increases the flexibility of the car.. because you might be able to drive it again later the same evening after a short recharge in your garage. (Same here, hard to “charge” faster than gasoline on a long trip, 5 minute refuel time is hard to beat, and you can certainly drive it later that night after the trip too). So the Volt supports all 4 of those points, and the Gen 2 does this while giving gas-free operation for 50 miles of driving per day, far in excess… Read more »

True. BMW’s i3 is a better solution.
Would like to see a Volt 3.0 with an i3 solution.

But, hybrids are the least-risk option until the grid of charge points is available.

Eric Cote

BMW is not a “better” solution, just a different one. Each has their merits.

The Volt has full acceleration and performance once the battery is drained. The BMW i3 Rex does not.

The Volt is made for worry-free long trips, and the i3 is made to reduce range anxiety on those trips that push the limits of its electric range.

Very different approaches with very different outcomes in the utility of the vehicle.


The article says:

“The E-REV, however, deserves a second look as a viable long-term technology.”

It does not. It’s strictly a stopgap measure. The only exception would be in wilderness areas where finding an electric outlet would be difficult. If you want to go on safari, then by all means use a gasmobile.

But otherwise, cars and light trucks will have no need for the crutch of a gasoline engine when battery tech advances to the point that the average EV has 300+ miles of range, and can be superfast-charged to 80% capacity in 10 minutes or less.


” when battery tech advances to the point that the average EV has 300+ miles of range, and can be superfast-charged to 80% capacity in 10 minutes or less.”
Wouldn’t that be long term? I don’t see this happening for at least 10 years.


Well of course I was talking long-term, kdawg. That’s why I quoted the author’s statement about long-term tech at the top of my post.


But in your post you said it doesn’t deserve a second look as a viable long term solution. So does it or doesn’t it? And “long-term” should really be defined. For me, a decade is at the lower end of “long term”.


… crickets …


We clearly have very different definitions of “long term”. I certainly wouldn’t define any period of time less than a single human generation (~23-25 years) as “long term”.

The period of time you’re talking about, say 6-20 years, I would describe as “mid-term”.

Eric Cote

Well, if we take the accounting definition, long term is anything greater than a year. 😉


+1 The good shouldn’t be the enemy of the perfect. There should at least be the choice of mainstream EREV and BEV. For poeople who tow, at 7mpg, or do long range, off the path recreation, I’d be confident it will be a net-gainer for the environment, too.


If DC-FCs were ubiquitous, I would agree with you.

However, they are not, and it’s unclear just how quickly DC-FC will become readily available and accessible to all. Just look at a map of DC-FC around the Boston area… it is PITIFUL!

I can’t afford an EV with a 300+ mile range, but I can afford an EV with a 200+ mile range (e.g., Bolt, M3, hopefully soon Nissan). But if I take a 150 mile or greater trip in a 200 mile EV, and there’s no access to DC-FC, I’m screwed.

BUT, if I take a 150 mile or greater trip in an E-REV (e.g., Volt), I’m fine…. even in the middle of winter. Because in most places, gas stations ARE ubiquitous.

And until DC-FCs are ubiquitous, E-REVs are the jack-of-all-trades best option for *most* people.


Please note my comment was about the long-term viability of PHEVs vs BEVs, not their present practicality or usefulness.

I entirely agree that at present, and over the next 10-15 years, PHEVs with relatively good range (so-called “EREVs”) will be more practical than BEVs. Unfortunately at present, the Volt is the only PHEV that qualifies. The rest have an electric range too short to count. With the advent of 200+ mile BEVs, I hope to see more PHEVs with a range of 50+ miles.


i3, anyone.


The BMW i3 was designed and built as a BEV, not a PHEV. Bolting on a wholly inadequate scooter motor and calling it the “i3 REx” perhaps causes it to technically qualify as a PHEV, but that doesn’t change the reality that it wasn’t designed to be one, and doesn’t function well (or even adequately) in gas-powered mode. It certainly wouldn’t be able to compete with a true switch-hitter like the Volt in the PHEV market, if the Volt had a larger back seat.


“but that doesn’t change the reality that it wasn’t designed to be one, ”

One can argue that they left that space in the i3 specifically for the REx.

So, they did have the REx in mind when i3 was designed.

If i3 was purely a BEV from the scratch, then the REx would have been in the frunk like an after thought…


The i3 was designed to have a low power engine with a ludicrously small gas tank.

The i3 was not designed with adquate power and range in gas mode to replace a normal ICE car.

The Chevrolet Volt does not have this issue, and neither does the Chrysler Pacifica PHEV, coming this fall with 16 kWh, 30 mile EV range (EPA), and all the passenger and cargo space of the ICE Pacifica minivan.



“The Chevrolet Volt does not have this issue,”

Actually it does as well if you don’t engage Moutain/Hold mode which i3 lacks.

Try to drive from SF to Reno on I-80 without hold/mountain mode, the Volt will go into “power limited” mode just before Donner’s pass at 70mph+ cruising speed.

So, BMW i3 can avoid the same thing if the battery is allowed to be reserved for steep/long climbs up a large mountain range.


ModernMarvelFan said:

“…they did have the REx in mind when i3 was designed.

“If i3 was purely a BEV from the scratch, then the REx would have been in the frunk like an after thought…”

Very well, you have indeed pointed out a flaw in my argument.

So, it would have been better if I had written: From all the reviews I’ve read, the BMW i3 performs very well as a BEV. But the i3 REx is a wholly inadequate PHEV, with a scooter motor (!) range extender which performs as if it was bolted on as an afterthought.


functions well enough in Europe. So, I’m confused, you seem to think the engine in Volt is too big and the engine in I3 too small. Is that it?


Was this a response to my post? I certainly don’t think the Volt’s gas motor is too big. It’s the only PHEV that’s a fully functional switch-hitter, so arguably it’s exactly the right size. A lot of people say the Volt’s back seat is too small, and I guess the car loses a lot of customers due to that. But that issue is separate from the engine size.


I’ve used a DCFC aka DCQC twice. Once to try it, and another time of need before an L2 was installed at home. Now I charge every third day, with just twice the range of the new Volt.

David Murray

I have found that there are a group of EV “purists” out there that will dismiss the Volt and other similar vehicles because they still rely on gasoline. Yet many of their arguments are totally invalid, almost to the point of it being a religion for them.

I just bought a 2017 Volt and I think it is the most amazing piece of technology I’ve ever seen. I have had it 2 weeks and still haven’t even tried the gas engine. But I know it is there in case I need it.

I may be hauling around several hundred pounds of engine that I don’t use every day. But I prefer that to hauling around several hundred pounds of extra batteries that I also wouldn’t use every day. And when I decide I need to use the engine for that really long trip, I’m going to be much happier to have it than I would be with a larger battery.

To be honest, and I know I’ll get flamed for this, but Tesla is too late. GM already introduced us to the affordable EV for $35,000 that has long range and great performance.


Also w/a 100 mile or less EV, many people also have a gas car as a backup for long trips. So they are storing, insuring, and registering another 3000lb device that they don’t use very often.


Here’s a flamethrower: EREV is plug in hybrid. To call it “EV” is somewhat misleading, especially ones without DCFC. As a hybrid, you have to worry about two sources of power. Whether gas parts gets used often is immaterial. Even carrying extra weight, single source is far better.

Now my turn for wearing the fire suit: given a choice between hybrid (plug in or not) and gas car, I’d take the gas car.


A plain gasser? Ew.


Yup, plain ole’ gasser. Had the Prius, never again a hybrid for me. Better hybrid is BEV + old gas van (or SUV or pickup). With basic insurace or per-mile insurace (MetroMile) and old car registration fee, cost isn’t much.


The problem with keeping an old gasser is the fact that when gas cars don’t get used often, they still “rot away”.

The tires still need replacement due to aging and chassis still need lubes and brakes still rusts away.

EREV/PHEV solves that problem by sharing the chassis and powertrain to the point of drive shaft so you only need to maintain 1 set despite that there are two power sources.


Old gasser is big car like van, SUV, truck. In effect, it becomes van/truck/SUV PH that can use DCFC, not just a small sedan PH without DCFC like Volt. Degradation cost is true, but still not so bad considering gas savings from not using it much.


So, no gasser now?

You are flipping back to PHEV again?

You flip flopper!


EREV is _not_ plug-in hybrid. EREVs _are_ PHEVs, but not all PHEVs are EREVs.

EREV has a specific purpose: elimination of engine starts. That means the only reason the engine runs is when you’ll exhaust the battery capacity.

(But to me the Volt is not an EREV because it doesn’t solve the heating challenge. I call it a full-performance PHEV. For a lot of people the Very Cold/15F setting is good enough)

And on the article itself:
Bolt curb weight is 3,580lb.
Volt curb weight is 3,512lb.
The idea that a long-range/long-distance BEV would _necessarily_ be a lot heavier is not correct. And it’s not like batteries are getting heavier.

I could also point out that the Prius Prime will be 200 pounds lighter, and that the Prius PHEV is 500 pounds lighter. Weight matters, but it’s obviously not the be-all and end-all.


Prius HEV*


If it’s got a gas engine and a plug, it’s a plug in hybrid, not EV. You can call it ERPH for likes of Volt or i3 REx and PH for likes of PiP, but they are still hybrids (gas + electric) with plug.

Conceivably, fuel cell plus plug could be called EREV. However, having two source of power, I would still call it hybrid: fuel cell extended range plug in hybrid electric vehicle, or FCERPHEV. Too many letter? That reason alone should be enough to ditch FC, but I digress.


And here’s the alternate viewpoint… the one that is taken by automakers and government regulators:

If you can plug it in and then drive it on the electricity you charged from the plug, it’s an EV.

You might prefer that “EV” and “BEV” mean the same thing, but the market disagrees. “EV” is currently defined by whether you are capable of running on energy from a plug, not by whether you are incapable of running on anything else.

Jake Brake

To add fuel to the fire… the Volt and Pacifica are both PHEVs, however only the volt is an EREV and FCA calls the pacifica a hybrid.


FCA avoids the PLUGIN label so their potential buyers won’t experience the EV range anxiety.

Somehow FCA views that as a plague to have the word “PLUG”.

RexxSee shares the similar view.

Now, we see why EV haters/EV Purist are both bad for the EV community.



“Here’s a flamethrower: EREV is plug in hybrid. To call it ‘EV’ is somewhat misleading, especially ones without DCFC.”

It’s only “misleading” for those who keep trying to redefine “EV” to mean only “BEV”.

PHEVs are EVs. In fact, so are HEVs, even non-plug-in hybrids which need a gas motor working in parallel with the electric motor(s) to push the car down the road.

If you mean BEV, then say BEV. Don’t try to get everybody to use “EV” to mean only “BEV”, because that’s not what the term means.


Well said,



Definition for EV is electric vehicle as in it runs on electricity, typically single source and typically battery.

Definition of hybrid is combination of multiple sources, typically gas + electricity.

To say that Prius is an EV is laughable, ridiculous argument. It’s gas-electric hybrid. Somewhere along the line, someone decided that it’s cool to call it EV for half a mile of AER, but hybrid is not EV.

Now Volt takes on same kind of nonsense instead of calling it what it is; gas-electric plug in hybrid, or PH for short. Appending EV is misleading.

Simple fact is, gas engine is not EV. Fuel cell could be called EV (or FCERHEV since they have battery), as distasteful as that is.


“Now Volt takes on same kind of nonsense instead of calling it what it is; gas-electric plug in hybrid, or PH for short. Appending EV is misleading.

Simple fact is, gas engine is not EV. Fuel cell could be called EV (or FCERHEV since they have battery), as distasteful as that is.”

Why is that fuel cell is okay to be called EV but gasoline REx can’t?

Can you run Volt without gas? yes. as long as you want! That is the difference why Volt should be allowed to have “EV” in its label.


Fact are that one use only one type of motorization while hybrid can use more in whatever way they can.
So the name should say how many type of propulsion is doing, or could d, the work for propelling the car.
So, if you have electric and something else, it has to be called hybrid.
But, that doesn’t mean that the Volt isn’t fine and much more so than many think and certainly not how it work.
But it just isn’t an EV, although it can work as one most of the time. It’s a sophisticated hybrid with a very long EVrange.
But if it is something that clears that for the majority, call it whatever you want.
The point here is that E-REV could be a much better part of cleaning transportation if GM would put it all over their model, if only as an option.


You can, like Humpty Dumpty in Alice in Wonderland, use any word to mean anything you please, regardless of whether it means anything to anyone else or not.

But if you want to communicate with others, then you’ll note that the “EV” in “PHEV” means exactly the same as the “EV” in “BEV”.

An electric vehicle is one which uses electric motors for propulsion, and that is all it means.

It doesn’t mean an EV like the Volt can’t also have a gas motor, any more than saying that because a baseball player hits right-handed, that means he can’t also hit left-handed. In real life, there are switch hitters… just like the Volt is a “switch hitter” between gasmobile mode and BEV mode.

Wrong. The more fuel choices you have the better it is. Why? Because, as you have probably noticed in the last few years, gasoline prices have rocketed and plummeted. For single source ICE vehicles, they have no choice but to ride the wave. The EV users, they also have no choice but to stick with electricity. Not sure about gas prices now, but it is getting close to the point where running on gas is cheaper than running on electricity. So the Volt has the best of both worlds. Personally, the EREV definition assigned to the Volt is dead on. You run entirely on electricity (EV mode) and when your battery is depleted it will switch over to Extended Range mode. This has nothing to do with the setup of the planetary gearsets and other technical info. When you are in EV mode, under normal circumstances, the engine DOES NOT COME ON no matter how hard you slam the accelerator pedal. In hybrids like the prius the engine always comes on, in the Volt, it does not. That’s why it’s an EREV and not a hybrid. Nothing to do with planetary gearsets. (FYI, this is response to an earlier post… Read more »
Texas FFE

I have both a PHEV and a BEV and I wish both my cars were BEVs. Maybe some of it is idolatry but most of it is practical. The BEV is much less complicated and, except for the cost of the battery, is much less expensive than the PHEV.

My PHEV is very nice but I think it will see the crusher long before my BEV does. Modern BEVs are very robust and should have no problems reaching hundreds of thousands of miles of use. Despite the current limitations of BEVs I think the simplicity and the environmental benefits will make BEVs win out over PHEVs in the long run.


Well said. Experience is paramount.


“odern BEVs are very robust and should have no problems reaching hundreds of thousands of miles of use. ”

Are you sure about that with the LEAF?

We know that there is a healthy 300K miles Volt. Is there a “healthy” 300K miles LEAF with original battery?

Sure, you can say that Volt battery only has about 100K miles on that 300K miles. But the point is about your claim of that BEVs would last longer….


“Come, sir; I think you’ve picked a poor example.” — Col. Pickering, “My Fair Lady”

Texas FFE

I believe that changing out battery packs on BEV will become a standard maintenance item, similar to replacing tires except a lot less frequent. Each time the battery pack is replaced there is the potential to increase battery pack capacity, so the performance of the BEVs could improve over time. A BEV should be able to go through many battery pack replacements before the vehicle is just too worn out to justify additional battery replacements.

I’m sure you have read that Elon Musk stated Tesla vehicles could last for one million miles, there’s no reason many of the other BEV models couldn’t last as long or longer. If my FFE wasn’t so limited in range and charging speed I would gladly hang on to it until it wasn’t fit to drive anymore. If there was any way to give my FFE the range and charging speed of the Bolt I would hang on to it indefinitely, but as it is I will try to replace my FFE with a Bolt when I can.


Yep, I’ve been driving my GM Model 3 for 3 years now. 71.3% electric miles with hundreds of thousands of 5-minute Superchargers everywhere.

It doesn’t accelerate or handle like a Tesla Model 3 will. Smaller inside. No OTA updates. But I’d buy another one. Best kept secret on the market today.

David Murray said: “To be honest… Tesla is too late. GM already introduced us to the affordable EV for $35,000 that has long range and great performance.” If GM planned to ramp up production of the Bolt the way Ford ramped up production of the Model T back in the day, you might have a point. But GM has no intention of doing that. They’ve pretty clearly signaled that by farming out the entire electric powertrain to LG Electronics and LG Chem. If GM intended high volume, they’d build the powertrain in-house, just as they do for the Volt. (I also think that GM needs to build its own battery factories to support high volume BEV production, but admittedly that’s debatable.) Tesla is committed to making their mid-priced, 200+ mile BEV in large numbers, as soon as they can ramp up production. GM isn’t, and won’t. Furthermore, even if GM did produce enough Bolts to meet demand, it’s still a vast overstatement to say that would make the market for the Model ≡ disappear. There’s room for more than one compelling mid-priced BEV in this world, just as there’s room for more than one best-selling gasmobile. When it comes to… Read more »

David Murray is talking about the Volt, not the Bolt. Not that he’s correct either way, though.

Stephen Hodges

Sorry, but you omitted the bit about larger batteries allowing you to own the car for longer, as you can accept some storage loss, and the fact that the battery will last longer anyhow because it is being used more gently


“the fact that the battery will last longer anyhow because it is being used more gently”

That is absolutely true on the “wear and tear” due to cycling part.

However, a battery still ages with time even if you use it gently. Unless it is stored at optimal temperature without cycling at all, it will still age at its “normal” rate with temperature it experiences with daily use…

Only time will tell how well the current crops of BEVs will fare in 10-15 years from now.

The earliest data we have are from the Tesla Roadster which isn’t a large sample. The result is sort of mixed…


VOLTers do a number on themselves. Trying to use it like an EV and suffering range anxiety while trying to keep the engine off. Carrying around thousands of parts to be serviced. Double the battery and drop the complexity.


“Double the battery and drop the complexity.”

It is called Bolt.

But still won’t solve the range anxiety issue with lack of infrastructure.


Bolt is 4x the battery. More than necessary for an in town car, most towns around the US. That makes pricing higher than necessary. They should offer a lower kwh base battery, the entry price would drop $5k. It is relegated to in town as it had no rural infrastructure. A bit rediculous to have 200mi base.


Agree with all the above comments.
Who wants to burn gas and lug around all the extra machinery that does nothing but make you visit the dealership more often.

I wonder if this Center for Advance Vehicular Systems has a grant from the Detroit giants.


One of the nice things about plugin-hybrids is that the need for servicing the engine is greatly diminished if the car is mostly driven electrically. You basically never need to do short trips on a cold engine, which is when most of the wear and tear happens in pure-ICE cars. Some PHEVs also don’t have a traditional transmission, don’t need a starter, and the brake pads last far longer too if you mostly use regen braking.


Not true if you drive in cold climate region.
The ERDLT start every time you hop in the car with a cold engine, cold catalyze, frozen lubricant, on a super rich mixture that pollute X time more and then and shut off after producing.
Thus using the ICE engine in the hardest condition and wearing it faster.


“but make you visit the dealership more often.”

6 oil change in 300K miles is too often?

I guess you forgot about the 300K miles Volt.


“In fact, it’s hard to imagine a scenario where electrochemical energy storage ever matches the specific energy or energy density of refined liquid hydrocarbons”

Yeah… What else was hard to imagine? Microchip, the disk drive, DNA, human flight, the internal combustion engine, (say when)…

I have no problem with REx, other than extra mechanical complexity, cost, taking up room, going to gas station, still using oil to move around, etc. Other than all that, perfectly viable solution “long term”.


I think the author is completely correct. I currently drive a plugin-hybrid and am quite happy with it. On most days I can do my commute and errands with pure electric driving, but I can still take the car on longer trips without worrying about charger availability. I’d like to have slightly higher electric range (something ~50 miles would probably do), but otherwise it’s great.

I have registered for a Model 3, but I doubt that I’ll be able to use it as my only car. I often take trips off the major transit corridors and just don’t want to deal with the hassle of meticulously planning every trip, additional overnight stays just to keep the car charged, or worrying about occupied or broken chargers. We are still far away from a ubiquitous fast charging infrastructure.


There isn’t even an RV campground along your remote routes? They all have NEMA 14-50.

Many folks rent a vehicle for long trips, even those with gas cars. When they break down, you just call for a replacement.


The EREV always made the most logical sense. As an engineer and a Volt owner, I can appreciate how engineers came up with the idea. The first kWh of battery displaces the most gasoline, with each additional kWh displacing progressively less.

But consumers are rarely motivated by logic. Even with its disadvantages, I think the pure BEV is more desireable to the average person. It’s easier for them to understand. Having two fuel sources seems to confuse people.

I think the pure BEV will catch on despite itself. Tesla has been able to make EVs desirable enough for people to overlook the shortcomings of battery cost, range, and refueling time.

(The large battery does also have the advantage of being able to supply large amounts of current to give ludicrous levels of acceleration. But again, that’s something that’s used for a few seconds, not all of the time.)


My experience owning a Volt for the past 2.5 years confirms virtually everything you wrote in your post.

Most importantly, most people are very confused by the EREV concept and as a result I predict it will never take off in huge numbers.

I affectionately refer to the Volt as the best car (almost) nobody ever bought.


The Prius, although not a PIV, is the optimal Gas/EV configuration. Much less costly, optimized for emissions, much lower weight, and beat the Volt to market by 15 years. Without it, GM would never have made the Volt.


It was the Tesla Roadster which inspired GM to make the Volt. Not the Prius.

The Prius is an excellent engineering design for a more efficient gasmobile. But every one of its miles is powered by gasoline. That’s not the wave of future transportation; it’s the last gasp of gasmobile tech.


Incorrect. The Volt was inspired by, and designed to compete against, the Prius.

Bob Lutz originally wanted to make a high-end BEV sportscar to compete against Tesla, but was convinced that Toyota and the Prius were the more important target.

This should be evident by the fact that the Volt is rather obviously more similar to the Prius, and not the Roadster or the Model S.


I didn’t say it inspired GM. It paved the way; without it GM would never have built the Volt to compete.


As an engineer and Volt owner, I also agree with you.

However, if it takes an engineering degree to “get it”, then it is already a lost cause.

Sad but true.

Volt is arguably the BEST CAR that NOBODY appreciates.


Well said MMF. I think you hit the nail on the head.

I love my Volt, but most people just don’t understand it and how much nicer it is to live with than other cars.



I find it incredibly sad that the purists bash the volt so much. End result? IN 20 years 80% of the population will still be using gas only

Mike I

Liquid hydrocarbons are a good answer. However, fossil liquid hydrocarbons are not. If you follow the technical articles at GreenCarCongress you will know that it is possible to make liquid hydrocarbons from nothing but electricity and water. Putting R&D and capital into developing infrastructure for synthetic liquid hydrocarbons makes a whole lot more sense to me than putting the same money into hydrogen fueling infrastructure. This has applications not only for automotive, but heavy trucks and aviation as well. This is one of the best paths to renewable transportation because you can gradually blend the synthetic supply with the fossil supply as you build up the infrastructure.


“it is possible to make liquid hydrocarbons from nothing but electricity and water”
Where does the carbon come from?


LOL! Yeah, I noticed that error too. Maybe he meant to say “Electricity, water, and air”?


The atmosphere, or waste CO2 from other processes. Shell Oil started a synthetic fuel plant in one of the Middle Eastern sheikhdoms at the start of this decade, whose product is supposed to directly replace gasoline. I guess this is just for research while they struggle to get the price down. It still takes energy to turn that CO2 into something else.

Mike I

You can either take the carbon from CO2 in ambient air, waste CO2 from other processes like making concrete, or from seawater. There is dissolved CO2 and carbonates in seawater. Notice that I didn’t say you should take CO2 from fossil powerplants.


Besides the weight, another important question is: what’s more reliable? a 10 year old engine that’s barely been used? or a 10 year old battery that has spent most of it’s time cycling between 100% and 75% SOC?


The battery, with today’s additives, the dendrite problem has been solved. You should have 90% of capacity in 10 years.


Are you sure about that?

See you in 10 years…

So far, the LEAF has confirmed the opposite.


Yeah, li-ion battery shelf life is the Sword of Damocles hanging over the longevity of BEVs. Even the Tesla Roadster isn’t yet 10 years old, so we don’t have real data yet on what will happen as BEVs enter their second decade of use.

But even if the 2010-2011 Leaf battery pack turns out to have relatively short shelf life, that doesn’t necessarily mean that all BEVs will be similarly affected. Battery makers keep fiddling with the chemistry, so yesterday’s batteries may last a shorter time than today’s. Or perhaps yesterday’s batteries will hold up better over time; who knows?

This is unfortunately just one example of how EVs are still in the “early adopter” stage of the technology.


The weight factor is over-rated. With gas cars, more weight means all the kinetic energy is wasted as heat. With EV (and hybrids, including PH), most of that energy gets captured (50%? 80% like L2?). Then the biggest impact is rolling resistance. At highway speeds, that’s 20% depending on cars.

If a car weighs 3500 lb for PH (Volt weight) vs 4000 lb for EV (Tesla S weight), that’s 12% difference. 20% of that as extra rolling resistance is only 2.5%. But Bolt weighs roughly the same as Volt, negating any weight factor in BEV vs PH.

We know SparkEV battery at 18.4 kWh (same as Volt) weighs bit under 500 lb while Bolt battery weighs about double. Does extra gas engine and all other items (gear, fuel ,etc) for Volt add 500 lb? I suspect they do. Meanwhile, Bolt will be quicker due to bigger battery than Volt. Weight simply isn’t a factor anymore thanks to GM engineers.

SparkEV said: “The weight factor is over-rated.” It’s over-rated to the point of being FUD, and I’m very surprised to see an InsideEVs article make an argument based on anti-EV FUD. In the first place, as I think someone already pointed out upstream, most of the energy content of gasoline is wasted in the gas engine. A properly designed EV is between 3 and 3.5 times as efficient in its use of energy as a gasmobile, so for a fair comparison, you need to compare only about a third of the energy in gasoline to the energy stored in batteries. More importantly: For BEVs to be fully competitive with gasmobiles on weight, it’s only necessary for the entire weight of the EV powertrain (including batteries) to be equal to or less than the entire weight of the gasmobile’s powertrain including a full tank of gas… plus all the kludges required to make the ICEngine practical in a car. Kludges like the exhaust system, which the BEV doesn’t need at all. And anyway, who cares if BEVs never compete with gasmobiles on weight? Have you ever heard anyone say “Well, I’d like to buy that car, but the curb weight is… Read more »
Dan Hue

The case for big batteries will be easier to make once we have V2G technology in place. In a future world awash in renewable energy, it will be valuable to have millions of cars with 10, 20, or why not 50 kWh of electricity on tap, ready to be traded on the grid (or consumed at home). Until then, and especially if supply of lithium becomes tight, EREVs (those with 40 or more miles AER) can still help us displace the vast majority of gasoline usage.


V2G? Anyone who agrees to wear out his EV’s battery pack to benefit the local electric utility is a fool. If the utility can afford a fair market price for wearing out your EV’s battery, then they can afford to buy their own batteries. And it should be cheaper for them to do so, because stationary storage battery packs should be cheaper than equivalent capacity EV battery packs.

Mike I

+1 – V2G for active EV batteries is nonsense except in emergencies.

In addition, the battery packs from used cars, crashed or degraded, should also be used for stationary storage.

Dan Hue

I disagree. In the context of significant renewable energy powering the grid, with electricity prices fluctuating based on supply (from very expensive to dirt cheap), demand management will be key. Given that most people only need 10kWh or so to commute on most days, some portion of a large battery pack (60kWh or more) could be used as buffer, intelligently managed by the grid operator, under the control of the EV owners. What is nonsense is the idea of V2G “wearing out” the battery. Anyway, time will tell.


“Given that most people only need 10kWh or so to commute on most days, some portion of a large battery pack (60kWh or more) could be used as buffer, intelligently managed by the grid operator, under the control of the EV owners.”

The question is how much are the Utility is willing to pay for those “unreliable” source of battery.

Utilities need reliable sources, that is why they pay for. If you are using your car, they would have to depend on that available power. So, if you are only 60% reliable (assume duty cycle of connecting to the grid), then they certainly wouldn’t pay the full price.

At what price will the Utility just buy their own battery instead of paying for a bunch of EV owners to make their car “somewhat” available?

Also, V2G need equipment for each and every car. Who pays for that? Will that cost exceed the centralize storage solution that Utility can control 100% of the time?

Those are all system level questions that need to be looked at and calculated before the V2G question is answered.

Dan Hue said: “…some portion of a large battery pack (60kWh or more) could be used as buffer, intelligently managed by the grid operator, under the control of the EV owners. What is nonsense is the idea of V2G “wearing out” the battery” I can see, in theory, that there’s a case to be made for the utility being able to use your EV’s battery pack on an emergency basis; to avoid a brownout or blackout. Such rare use certainly wouldn’t wear out the EV’s battery pack. So if that’s the point you’re trying to make, then I agree. The problem with even that optimistic scenario is that the EV would still need a two-way charger installed, to allow the EV to provide power to the grid. Who is gonna pay for the extra expense? Does it make any financial sense for the utility to pay for something that it would use so rarely? If that’s worth the money to the utility, why isn’t it worth the money to just buy more stationary storage capacity, so it wouldn’t need to rent storage capacity from EV owners? Why shouldn’t the utility buy its own emergency backup storage capacity? Nope. No matter… Read more »

You’ll have the option to rent the pack.
But by then, homes will also have packs and downed-grid capability. More reliable distribution of available energy for grid stabilization, too.


whoa, that argument seems totally backwards to me. If there’s a viable business case for a utility to buy a dedicated battery, that would suggest the value is high enough that they could pay EV drivers a pretty high price to make use of an existing battery that’s already paid for and that’s just sitting around. Put another way: the wear and tear caused by cycling a kWh is going to be the same regardless of who’s battery you’re using – so is it cheaper to buy a dedicated battery or pay someone to use theirs when it’s sitting around?

I’m a skeptic of V2G in general, and I think dedicated batteries are definitely similar. But i would hardly say that a viable business case for dedicated batteries is the sign that V2G doesn’t make sense.


As “a viable long-term technology”, private cars have no future.


While the author is completely right with energy densities, ask him about power and he will start to stutter. Just look at the i3 in EREV mode and you will see what I mean.

Bob A.

Heavier, lighter, this energy, that energy, old, new, your way, my way, bleh.

The real name of the game is total cost per mile over the life of the car.

Do that for vehicles with 100 miles range, 200 miles range, etc. and hand it to the consumer. Let them pick.

If they only need a 100 mile range car for 99% of their driving, and are willing to rent a car for that last 1%, they can judge that.


Bob if total cost per mile over the lifetime of the car, that white Honda Civic mentioned above is going to come pretty close to any BEV or EREV out there. Until gas prices go back up, at least. And if you buy it used and change the equation to over the time you own it, it would be hard to beat indeed.
But I think most of us really do want to have a car that is fun to drive as well as uses electricity, as much as possible for EREV drivers and all the time for BEV drivers. Horses for courses.


Auto makers have had over a century now to bring down the price of making gasmobiles. If we’re really talking about the long-term outlook, it certainly will take less than a century for the purchase price of EVs to be brought down below comparable gasmobiles. With battery prices dropping at an average of 8% per year (per kWh), and with production of BEVs being scaled up to benefit from the economy of scale, that should happen within a couple of decades or even less. For all I know, it may have already happened in China.


Here’s a better idea. Just tow the extra battery capacity when you need it. Heck, just rent it for trips. So 200 mile range built in, 200 more in a rentable trailer for road trips. This also makes battery swapping possible, just swap trailers at a service station. Now the charge time argument goes away as well.

This was covered on this site 2 years ago:


Also, if you put some cargo space in the trailer, now you don’t need a roof rack for your skis.


EV are prohibited from towing anything except Tesla X and soon Tesla 3. If EV are allowed to tow, they can conceivably tow gas generator to provide Volt level of range, 500 lb gas engine + generator, while allowing full EV driving for most situations. Well, maybe Tesla 3 PH (or as this article calls, E-REV) version could do that.


Just who do you think is prohibiting towing by EV passenger cars and light trucks?

I assure you, lots of people are doing that, even if the auto maker doesn’t approve. In fact, pretty much any car can be used for towing, so long as it’s a light trailer.

From “Should You Tow With The Tesla Model S?”


Sure you can tow with anything, but you’re taking a huge risk in voiding the warranty. Not only can they deny for transmission (one gear) problem, but they could also deny for battery, motor, etc by saying towing stressed them. SparkEV battery out of warranty could cost $22K, even more than new car price before subsidy! It’s not worth the risk of throwing away the car by towing.

This is why Tesla3 having towing capability is huge. It could open up range extender, not only as bigger battery but also gas generator. Then it’ll really be EREV in true sense of the acronym.


Instead of comparing Specific Energy Density of gasoline with chemical batteries, why not compare to other extended-range fuel types?

A more interesting graph would be specific energy on one axis and the amount of GHG (COx, NOx, etc) emitted over 100 km (60 miles). Energy density is but one factore of hundreds as engineers design a vehicle. A major factor is the cost (building, operating, health and environmental) for using a particular energy source.

BTW: torque where the wheels meets the road is what will win any driving challenge, not the density of energy.

Someone out there

I think there is another issue at play. The established car industry is happy with making minor improvements year over year so they can sell “new and improved” every year. They don’t want to make big changes in one go, they don’t want the next year’s car to be *too* good. That is why it’s supposedly a big thing when the Plug-in Prius goes from 5 miles AER to 11 miles.


I prefer a pure BEV like the Chevolet Bolt. Not (much) heavier as an E-REV. Very spacious, reliable, a good range and great performance. Thats all I need.

Kevin Z

I would imagine a heavier car is smoother riding. Also because of inertia, a heavier vehicle will have more regenerative braking.


But heavier car will pay the penalty on hills, during acceleration or when turning…

Yes, lowering Center of Gravity will help handling, but it won’t help the uphill or acceleration part.

It is physics.

“The Tesla Model S has a rating of 38 kWh/100 miles, while its EREV cousins – Fusion Energy, Volt, and i3 have ratings of 37 kWh/100 miles, 31 kWh/100 miles, and 29 kWh/100 miles, respectively.” Wow, yet another author who thinks all cars are appliances. No one expects a BMW 735 to get within 20% of the energy usage of a Ford Fusion ICE, a Chevy Cruze, or the closest ICE equivalent to an i3, which I guess would be a Mini on steroids. The Model S is a big, fast luxury sedan. Those other cars aren’t. You’re just like the people who complain that a Model S is more expensive than a Camry. I’m really getting tired of people who think that cars must be compared to each other on some absolute scale of utility. They must think that Rolls-Royces weigh 6000 lbs because they’re badly designed. They can’t imagine human beings buy big cars for reasons – even reasons we might disagree with. Someone who understood such things would see that the question is the opposite: why does the Model S use so little extra energy compared to cars that are so much smaller and slower and less… Read more »

Furthermore, if you compare the EPA range ratings of the Model S and the Leaf in the year they used the same EPA test cycle — 265 miles / 85 kWh vs 75 miles / 24 kWh — they have almost precisely the same miles per kWh.

So those who think the Model S isn’t energy-efficient as compared to other BEVs… need to think again.


” 265 miles / 85 kWh vs 75 miles / 24 kWh ”

Isn’t LEAF rated higher than that?

The 75miles was only due to 90% charging rate where it is 100% for the Model S.

I believe the following model year LEAF was revised up to 84 miles?

The EPA keeps changing its rating system. Initially that was good; rating the Volt at “230 MPG” was highly misleading, and frankly downright stupid. But continuing to fiddle with it every year just causes confusion… such as with the discussion we’re having right now. The EPA’s rating of the Tesla Model S85, made in 2012 and not changed since, tested the car on an 80% charge (which is what Tesla originally recommended, and perhaps still does) and on a 100% charge, and averaged the two sets of figures to come up with their range rating. The EPA did the same initially for the Leaf; averaging together range data from 80% and 100% charging. As I recall, the first year (2010-11), the Leaf was rated at 73 miles. Then it went up to 75 miles; perhaps that was the slightly improved 2013 battery pack? But then, Nissan removed the ability to select an 80% charge from newer Leafs, so the EPA rated it for that and following years only using 100% charge data. That’s how the Leaf went from 75 to something like 82-83 miles… altho there was no hardware change in the Leaf’s powertrain at all that year! Apparently Nissan… Read more »

Instead of doing all the math,

EPA clearly provides us with the efficiency rating of MPGe or Wh/100 miles consumption rate..

Tesla is higher than LEAF.


We seem to be overlooking something called legislation, that seems to have quite a impact.

Just the government announcing plans to ban cars that have emmisions at all is sending a huge signal to the car makers to get ready. You only get warned once.

Since that is planned for 2025 or 2030, depending on which version, you’d better have something decent full electric ready by 2020.


I’ve tried to say this before without much positive feedback, but I think a perfect combination would be a 60-70 kWh car and the possibility to fit some extra in the frunk. They could usually be stored in the Powerwall in the garage or at a local store.


The Powerwall doesn’t need a heater, or a cooling system. Put it into an EV as an auxiliary power source, and it will need both. That means it would also need its own radiator/condenser. It might even need its own charger.

Not very practical.

Brave Lil' Toaster

We’re going to start a revolution! We’re going to smash the establishment but keep the bureaucracy in place to keep things running!


If the object is to get rid of gasoline, we can’t be clinging to the security blanket of gasoline infrastructure. We need a new infrastructure that replaces the old. The only way that will happen is if we demand new infrastructure because we *need* it, not because we want it as a kind of nice-to-have. If we do it like that, we will literally never transition out of gas. No new DCQCs will be built. The people at GM and Ford will say “what do you need *that* for? you have this other thing”, and no fully BEVs will ever be built.

Without having EVs that are all electric all the time, we wouldn’t be where we are today. In fact, we’d probably have some tepid thing like the Volt and CMax forever. “Why change?” would be the mantra.

Tepid Volt? DOE data shows Volts in the US driving over 90% as many electric miles as the Leaf! And meanwhile, GM is going to be first out the gate with a 200 mile affordable BEV. I think PHEVs will only accelerate the transition to gas-free driving, due to the large portion of the market that would rather by a gas car than have to change any of their habits for longer trips. Sure GM’s commitment to investing in the infrastructure is basically non-existant. But is that because they don’t believe BEVs are coming? Or is it because they have a genuine disagreement about whether or not it’s their responsibility to invest in that infrastructure, instead of utility companies or third party service providers (as analogies to oil companies and gas stations with stores that make money). I disagree with them on that front, and i’m happy to see that Nissan, BMW, VW and other automakers do think they have a role to play in the infrastructure, but my main point is that GM seems committed to at least building class-leading BEVs, and yet they still see an important role for PHEVs. On top of that, we are already witnessing… Read more »

mustang_sallad said:

“Tepid Volt? DOE data shows Volts in the US driving over 90% as many electric miles as the Leaf!”

The Volt is certainly anything but “tepid”; it’s by far the most robust PHEV on the roads today.

But let’s not cherry-pick facts, hmmm? shows Volts, on average, get 71% of their miles from electricity. Not 90%. The figures you cite may indicate nothing more than Volts being driven farther per day, on average, than Leafs.

But some of those Leaf drivers, and also some Volt drivers, are also driving gasmobiles, and those miles aren’t being counted in the figures for Volt and Leaf driving. So, attempting to draw other conclusions from the figures you cited would be making assumptions in the absence of evidence.


You’re talking about two different numbers. mustang_sallad said that Volts are driving 90% as many EV miles as Leafs are, which has nothing to do with those Volts’ ratio of EV to gas miles.


What you are proposing is a model unlike every other technology advancement in history.

We did not immediately get rid of all lanterns when electric lights were invented. We did not immediately get rid of all telegraphs when telephones were invented. We did not immediately get rid of all horses when cars were invented. We did not immediately get rid of all radios when televisions were invented. We did not immediately get rid of all B&W TVs, or color TVs, or analog TVs, or EDTVs when the next iteration came along.

It has ALWAYS been a gradual process.

Why would


Chart is BS.

For cars what matters is total “cost” of equipment in KG for a energy that will be delivered to the wheels.

That means 2/3 reduction in that gasoline energy density, cause 2/3 will be wasted as a heat.

Electric motorls are also smaller and lighter then ICEs. Less piping, more electronics. Less gears in the gearbox (if any), etc.

Its quite naive to compare only energy densities thus. There is always “minimum” KG price tag for each technology (when aiming at the same HP/kW of output at the wheels).

Thus Tesla has only 50% of the range of comparable ICE competition.

WTF? You say. Well ICEs are allowed to burn in vain that much energy to move around.


Heat isn’t waste in winter. Many battery car drivers in Norway or other Northern countries carry third party fossil fuel heaters for that reason.

1/3 or 2/3 or whatever is the same order of magnitude. As you see from the graph, specific energy difference is many orders of magnitude. It would be a big issue, but you can’t charge electrochemical battery as fast as refuel. 1 MW chargers are not on horizon.


zzzzzzzzzz said:

“Heat isn’t waste in winter.”

Of course it is. The tiny amount of waste heat harnessed to heat the cabin* certainly doesn’t give us reason to ignore the 95%+ of waste heat which isn’t harnessed for any useful purpose.

*Yes, I know that if it’s harnessed for a useful purpose, technically that means it’s not “waste heat”. But that doesn’t alter the engine’s Carnot efficiency rating.


It is not tiny. I guess you never lived North or didn’t pay attention. More efficient diesel cars with less extra heat are even forced to use extra heaters.
Anyway extra heat makes range more predictable. Range may drop in winter, but not to 50% or 30% summer range. Now when you burn coal or gas and emit 50% or 70% heat to atmosphere to provide electricity for inefficient grid with 100% availability, so that you would be able to charge your “efficient” car ignoring everything beyond your personal outlet, that is really waste.


Seriously, zzzzzzzzzz?

It only takes about 1500 watts to power an adequate cabin heater. How much energy, if measured in watts, does an average car’s ICEngine emit as waste heat, considering that the engine is only about 15-25% efficient when in actual use in real-world driving?

1500 watts is indeed a rather small fraction of the energy wasted by an ICEngine. And keep in mind it’s wasting that much energy all the time the engine is running… not just when you’re running the cabin heater.

Bill Howland

1500 watts for a car heater is dead wrong.

My volt and elr have 6000 watt heaters, and in cold weather they are semi-anemic – so much so GM insists on arbitrarily starting the engine to make sure the windshield defroster will work.

Running my heaters on high uses ALL the spare jacket heat from the engine – the coolant never gets hot enough to open the radiator thermostat, at least in the ELR where the engine is run soley to provide heat for the cabin, and the rest of the car is pushed by the battery.


I know it is blasphemy in Musk church (true believers please close your eyes & stop reading here not to be offended), but hydrogen specific energy is higher than gasoline, 33,300 Wh/kg. And fuel cell stacks are getting lighter, smaller and cheaper quite quickly.


You can often tell when someone is making a B.S. argument by they way they cherry-pick facts which aren’t actually relevant to the debate… as in this case.

1. If you include the weight of the tank used to store H2 at 10,000 PSI, it weighs considerably more than gasoline (and its gas tank) with an equivalent energy content.

2. You’re comparing only gravimetric energy density. With a volumetric comparison, gasoline has a much higher energy density.


I told you do not read this blasphemy. I may point to technical data that makes your own arguments B.S.:
Fuel cell stack weight is 123.5 lbs (56 kg), while the hydrogen tank’s weight is 192.9 lbs (87.5 kg) (from ). It is less than typical car engine with gearbox alone.

It is more than gas tank, but it is the same order of magnitude, and it is just early production model. Equivalent battery would be more than 1000 pounds and would charging/refueling speed slower by an order of magnitude.


Another way to tell when someone is making a B.S. argument is when they try to use a bait-and-switch argument after you’ve pointed out what they’ve said is factually incorrect.

Like, for instance, trying to switch the argument to the weight of a gas motor and/or a battery pack, when the original assertion concerned only the weight of gasoline vs. compressed hydrogen.


The only acceptable EREVs in my mind today would be heavy trucks (e.g., garbage trucks) or off-road vehicles (think: Jeep Wrangler).

Why the Wrangler? Could you imagine a Wrangler’s off-road capabilities with two or four electric motors with 0 RPM torque? Couple that with a smallish battery and an ICE to ONLY work as a generator, and you would have a hellish off-road beast.


Good luck with that. How impractical is that???? If you.

Eric W

His Numbers are all wrong. Anyone can go to and look up the values link below shows cars.

2016 BMW – 27 kWh/100 miles

2016 Tesla Model S 90D – 33 kWh/100 mi (294 Miles of Range)

2016 Honda Accord – 109 kWh/100 mi (3.3 Gallons gas per 100 mile- 30 mpg)

2016 Toyota Camry – 119 kWh/100 mi (3.6 Gallons gas per 100 mile – 28 mpg)

2016 Average New Car – 132 kWh/100 mi (4 Gallons gas per 100 mile – 25mpg)

So after 125+ years of “continuous improvement” of utilizing the immense power stored in gasoline this is all we get in an average NEW car without a battery, 25 mpg (8.25 kWh of useful movement per gallon)? After 5 years of improvement we have an electric car that can go the equivalent of 12 gallons of gasoline (after ICE being perfected for 125 years). Imagine the amount of gasoline you will need to keep up with the same electric car after 10, 15, 20 years of EV and battery improvement.

I think were going to need a Bigger Gas Tank.

I don’t have that black or white point of view. Actually I want it all. A big battery with automatic charging capability, supercharge capability and extra range extender. But I want everything to be perfected as far as possible. The battery of course in the 150 KWh to 200 KWh range, the automatic charging capability so that I just have to park the car in my garage and some system on the ground takes care for the recharge, the supercharger that I want at a higher voltage to be able to go faster at 500 KW or 1000 KW power level charging the large battery in 5 to 10 minutes and the range extender that must be not compact but super compact so that it doesn’t really matter anymore if you have on in the car or not but at the same time I still want it to be able to pump out 15 KW of continuous electric power from a biofuel tank able to contain 60 liters. So if there is no charging possibility for whatever reason be it blackout, war, traveling through Siberia, Alaska or the Gobi desert, I can still carry on. By the way I like… Read more »

Here’s the thing with the Volt . . . if you are going to build a car that small, then you can just go ahead and make it fully electric. GM themselves are doing that with the Chevy Bolt! (And Tesla with the Model 3.)

Put the Voltec drivetrain into bigger vehicles! Those are the ones that need to be PHEV because they are too hard to do as pure EVs.


CT6 PHEV is coming right?

But I agree. Instead of giving us only 1 new PEV every 1.5 year (Volt, Spark EV, ELR, CT6 PHEV, Bolt), we can use 2-3 new PEVs every year from GM.

Put it in every configuration that GM makes.. Spread the love so to speak. =)


The article’s focus on energy density charts and the relative efficiency of electricity is misleading and besides the point. The point is priority and practicality.

The priority is covering as many miles with electricity as reasonably possible, because electricity is clean and gas is noxious.

The practicality is the vehicle’s cost to the owner; the number of times the owner is going to travel significant distances; and the number of cars the owner can have.

If the owner travels significant distances on a regular basis and can have only one car and can’t spent a boatload (read “Tesla-load”) on a car, then an EV-ER is the best way to go. Otherwise, get both a BEV and EV-ER, or get a 300-mile supercharging Tesla, or if you don’t often have to travel far then get an EV and occasionally rent / ZIP a car.

The right tool for the job.


The article stepped on someone’s toes, eh?? I congratulate the author.

I find it hilarious how anything burning oil gets the Tesla fanboys witch hunt treatment, yet charging from a grid powered by 70% of coal is OK.

The hypocrisies are loud and clear. Not Tesla’s not good, eh?


Gosh, I’m so sorry that on the planet where you live, EVs can only be charged off grid power using 70% dirty coal energy. Fortunately, the rest of us live on Planet Earth, where renewable options such as solar and hydroelectric power are available, and even average grid power is significantly cleaner than that.

Now, unless you actually have something useful to contribute to the conversation, kindly crawl back under the bridge where you came from.

Tony Willams

Nationwide (USA), coal has been replaced by natural gas as the number one power source for electricity.

In the singular state where most of the EVs are sold, California, there hasn’t been a coal mine in about 100 years.

In states with high EV sales, like Oregon and Washington, most of their power (by far) comes from wind and water (hydro).

But, we do know where gasoline comes from and what it does to the environment. Hybrid cars (no matter what acronyms are associated with them) burn gasoline. This creates the following situations:

1. Status quo infrastructure – hybrids don’t need EV infrastructure, as all destinations can be provided for with existing gasoline stations.

2. Supporting gasoline

3. Did I mention gasoline?


I agree with your points. But…

“In the singular state where most of the EVs are sold, California, there hasn’t been a coal mine in about 100 years.”

This really has nothing to do with it since you don’t have to burn the coal mined in your own state. So whether coal is mined in cA really don’t matter in this case. If it is mined else where and then shipped to CA for burning, then it would be even worse due to added transportation pollution.

CA grid has very little coal fired source now. That is the key point here.

CA Grid is more like an island. Although, CA is talking about extend the grid to neighbor states such as WY, ID to alleviate the peak solar generations… However, that connection would potentially link up the dirtier grids from those states.


The grid is cleaning itself faster than you can educate yourself.
Coal is barely alive, and you should notice it!


Highly misleading – Not taking into account the 80% heat and friction losses of gas engines.
Yes, some PHEVs and ERVs will be needed in the short term but the over-riding consideration is saving the atmosphere. Every possible gallon of gasoline must be phased out asap.

It seems the author is still in denial. I can’t blame him, he has spent his entire career building up a vast body of knowledge on internal combustion engines and is now seeing that it will be next to worthless in a few years. As others have pointed out, the showing of a graph only comparing energy densities, without accounting for drivetrain efficiency and weight is very misleading, and thus confirms my view. He is primarily misleading himself to continue the belief that there is still a rosy future for the ICE. Does he really think that consumers pore over energy density charts to choose their next car? He may know a lot about technology, but understands nothing about consumers. They just look at the product and ask themselves: does it suit me and can I afford it? They don’t give a hoot about what’s under the hood (or floor or rear seat for that matter). I hate to bring the news to him (and apparently, a lot of others here). It’s game over for the ICE. Nobody in their right minds is going to lug around an intricate, fragile and expensive machine consisting of thousands of carefully machined parts… Read more »
Tony Williams

Just like the “range extender” horse pulling a Model T Ford (after it ran out of gasoline), we are within a generation of making hybrids obsolete.

Ubiquitous quick charge infrastructure (and not gasoline stations) are what will enable this move.

Hybrids using gasoline promote the status quo. EVs require change. Change is scary and difficult for some.


More choices grows the overall EV market, and the Volt helps. For some of us, our driving habits make a lot more sense for a Volt than a pure EV. But in some places, the DCFC infrastructure makes pure EVs realistic. But I certainly can’t drive to South Padre Island, TX in any pure EV, even though we stayed in a guest house with a 120v outlet… BTW, my Volt is about 86% EV.


Very true! I agree with you guys 100%. but they need to put even more effort into the batteries and motor and less on the engine. 250hp motor, 25kWh battery would be awesome.

All the engine needs to do is run on constant optimum rpm and deliver electricity to either the motor or the batteries. 0,8l/100km or 30mpg is fine since it will be driven so seldom.


Let’s say the following car exists:
1- Big, family car
2- thirty kwh battery
3- small, inefficient, simple, light, cheap generator
4- capability to charge battery even if not depleted

This car would be able to
1- carry most people to work everyday without using gas
2- make us feel a lot safer about our purchase (no leasing here)
3- travel anywhere in the world
3- travel in comfort
4- save a few Euros when traveling, after all, electricity ain’t exactly free and gas is not that expensive. How much do you honestly believe you will be paying for those quick charges? Tesla model not viable, sorry (was, when they were selling 130k dollar cars, not anymore)
5- save fuel everyday since they CAN make it that much lighter
6- be a lot cheaper than equivalent BEV

Conclusion, once the hyperbolic dust settles, I believe everybody will need to accept BEVs are not and will not, for a long time, be the one ring to rule bla bla. If, and only if, you drive miles and miles to get to your suburbia, by all means, buy Bolt. if you don’t drive all that much everyday, then why?


Forgot to say, the other family car could probably be a 30 kwh leaf. Spark seems really nice but we don’t get that.

Bill Howland
I always disliked the term EREV – I have an innate distaste for superfluous abreviations and the Volt always minimally satisfied the term anyway, as performance was better with the engine. The ELR and new Volt are even more distant from this definition supposedly designed for this car to begin with, which it doesn’t meet. Another nagging “EREV” issue is I have no control over when my vehicles autonomously start their engines – a prime example of GM’s arrogance. But that goes right along with the GM’s engineering group refusal to discuss issues with me, but they WOULD chat with a dealer. Fine – I just racked up warranty car rentals, and burned out fuel pumps until GM refused to provide any more, and I finally found out what was going on anyway. They can be arrogant all they want, their stupidity simply cost them $$$. I’ve always referred to my 2011 volt as a hybrid with a plug option, even though the vast majority of trips are done with Utility Juice rather than gasoline. I can only hope that competitive pressure from the ENERGI and Pacifica plug-in models puts some friendly heat under GM to release larger models. They… Read more »

“If they asked LG to release an Escalade 60 kwh PHEV battery package to get this sized battery into at least the EXT (extended) versions of the car, then they’d have a great 100 mile AER.”

Do you think a 60kWh would get Escalade 100 miles AER? I highly doubt it especially with its weight and boxy aero which is about as bad as it gets…

Secondly, do you think another $30K cost on top of the Escalades will make the $80K car more appealing at $110K right up against a Model X?

Bill Howland
Certainly. The escallade, generally considered to have ‘poor’ reliability, would be great compared to the X. Just as an observer now, since I no longer have one, but to me the X seems much less reliable than the Roadster at any time. Supposedly George Clooney had his die on him, but I wasn’t aware the early Roadsters were a general problem as the doors are. EPA 100 miles? Well probably not the way the average Caddy owner drives. But if I’m careful I can go over 50 miles in my 2014 ELR when it is ‘EPA RATED’ 35. But if a BOLT can go over 200 miles, I just guessed a big SUV can go 1/2 that. I haven’t seen an “X”, but an Escalade, especially the “EXT” models have to be almost double the size. If you don’t like 50 and 100; then say 1/3 as far – like 35 and 65. Even a 65 mile ELR would be great. And what does a 60 kwh battery cost now? $10,000? And lets be generous and say ancillary items cost another $3000. So GM charges $15,000 more for the plug in version (60 Kwh) versus the hybrid with the small… Read more »
Bill Howland

err: AER not ELR, hehe..

Incidentally, my ELR is growing on me – I certainly got other ELR owners mad who absolutely LOVE everything about it, when I said I just like the basic car but hate most everything else about the gadgets, and hate the lack of input I have into the car’s decisions.

But the basic car is SO NICE that I ignore everything else. And I’m very surprised that the car gets as many ‘looks’ as the Roadster – apparently it is considered by the general public to be the most beautiful modern cadillac, or else they are just surprised that they’ve never seen it before.

Reliability wise, I’ve had the car for 1 year and have had ZERO issues.. Amazing.

And for everyone who calls the car overpriced, I paid just slightly more for it than I did for my admittedly overpriced, loaded 2011 volt, which I still also have.