Via Green Car Congress comes a number of perspectives on Plug-In Hybrid (PHEV) adoption fom the 2009 SAE Hybrid Technology Symposium. And there are some interesting lessons to be learned. One consumer study by Dr. Ken Kurani of the UC Davis Institute of Transportation Studies indicates that mainstream consumers favor less PHEV capability than manufacturers are developing. The ITS study asked a sample of plausible early market households (neither pioneers, advocates nor experts) to design their own PHEV, and found that expectations of all-EV range and battery capacity were remarkably low. Says Dr. Kurani, “consumers right now, given the opportunity to manipulate the idea of a plug-in vehicle, are designing not only very different vehicles, they are designing vehicles that are much more possible than the experts are assuming.” How so?
The survey shows most consumers see their battery requirements to be equal to or less than 2kWh, as all-electric range does not rate very high on their priority list. This contrasts sharply with Chevrolet’s Volt project which envisions a 16kWh battery capacity and 40 mile all-electric range. Despite the PR benefits of “40 miles without a drop of gasoline” lines, it seems most consumers in Kurani’s study designed models which emphasized fuel efficiency and blended gas-electric operation.
Meanwhile, Steve Plotkin of Argonne National Laboratory’s Center For Transportation Research argues that PHEVs will face increasing competition from incrementally improved ICE drivetrains. “The competition against PHEVs in 2030 is likely to incorporate a radically downsized, boosted direct-injection engine; an automated manual or 7-8 speed automatic transmission; advanced tires with CR at 0.006 or below; a 30% weight reduction on the glider; advanced aerodynamics with CD of 0.22 or below; advanced accessories; and a mild hybrid drivetrain,” according to Plotkin. He argues that consumer uncertainty tied to unpredictable energy costs means PHEV technology is not likely to be widely enough adopted to justify huge investment or government subsidization.
GM wants to give the vast majority (>75%) of drivers a gasoline-free “motoring experience” (read: commute to work). I suspect someone, a couple years ago, started whispering stories of doom-and-gloom when it comes to petroleum supplies circa 2015, and GM figured that it could be a hero by allowing Americans to continue driving to work each day. This drives the requirement for 40+ miles of EV range.
At AABC last year, Argonne and Toyota seemed to be leaning in the opposite direction. Instead of providing a battery so large that most drivers would never use the ICE, the battery should be so small as to ensure its full depletion by the majority of drivers during a daily commute (if the battery is the most expensive component, then why not use all of it every day?). An EV range of ~8 miles covers 75% of American commuters; beyond this, folks can use the ICE to extend the range.
Per Argonne’s calcs, GM’s approach makes sense at current battery costs and $10-12/gal fuel – assuming that people can afford a car with $15k in batteries and $10k in motors, generators, and inverters. At $5-6, the Argonne/Toyota approach is much more logical.
Per the above post, making these sort of decisions in light of uncertain fuel costs and competing technology ain’t easy.
The 50mpg vehicle they describe is quite close to today’s Prius and Insight. And the advantage of the Prius’ parallel hybrid drive is that plug-in capability can be easily added (as it will be in 2010) to the degree that the consumer wants, and is willing to pay for. And that will be driven substantially by gasoline prices.
I wonder if the typical PHEV buyer understands that it’s the energy stored in the batteries that’s enabling the high mileage of their vehicle and it’s the stability of electricity prices that’s their best hedge against petroleum price instability. A 2kWh pack is only slightly larger than the standard 1.2kWh in a Prius and far smaller than the 10kWh Hymotion PHEV kit that goes for $10k and delivers 100mpg.
He argues that consumer uncertainty tied to unpredictable energy costs means PHEV technology is not likely to be widely enough adopted to justify huge investment or government subsidization.”
The unpredictability of energy costs doesn’t make sense if you’re getting the energy from electricity, as mentioned before.
Also from the article:
“All electric driving may not be a bad idea for consumers, Kurani noted, it is just one that they don’t yet value or understand.”
“Miller stressed that it is important to regognize that hybrids are still favoured by consumers, and that it is important that automakers not start behaving like they don’t believe in the future of the technology.”
Just making sure both sides of the article are represented fairly…
If you ask a bunch of people, who aren’t used to designing anything, to design something that they don’t understand, they will likely come up with something based on what they do understand, and it won’t likely be a great stretch from that they already know. The capacity for design and vision is not something that everyone is gifted with, and takes years for some people to develop. The average consumer barely understands a current hybrid, let alone advanced technology, so this does not surprise me.
It is still imperative that automanufacturers take the lead, and show the public what is possible.
“The competition against PHEVs in 2030 is likely to incorporate a radically downsized, boosted direct-injection engine; an automated manual or 7-8 speed automatic transmission; advanced tires with CR at 0.006 or below; a 30% weight reduction on the glider; advanced aerodynamics with CD of 0.22 or below; advanced accessories; and a mild hybrid drivetrain…”
All of which (save the engine and transmission) could just as easily (and certainly will) be applied to PHEVs, E-REVs, or EVs to increase thier efficiency, or similarly reduce the battery pack size and price, thereby negating thier advantage. This argument is horribly flawed, especially considering that many of these advancements have shown up in hybrids or EVs first. The new super efficient Bose stereo going into the Volt would be an example, designed specifically to reduce electrical load.
I wonder why everyone is so eager to pick a winner or declare a loser? Every article which tries to do either ends up saying “of course, with energy prices so volatile all bets are off” or something… so how does predicting 2030 technology make any sense at all?
If people can start to think in terms of transitional technologies it makes more sense. Gas isn’t going away anytime soon. it might get more expensive, but many will still want or need to use it. Likewise, electricity isn’t getting any cheaper or cleaner anytime soon, but incrementally it will (get cleaner at least.)
So if the market provides a variety of 100 mile PHEV’s, 40 mile pure electrics, and honkin’ V8 Corvette’s then everyone can make their own choice.
The comments discussion reminds me of gm-volt.com, where fanboys deride the Prius as yesterday’s technology. Even if they were actually, you know, not living in fantasyland, the (current) Prius would be the #2 most fuel-efficient car in that hypothetical country (where the Volt actually existed and could be produced before GM closed its doors). People would still be buying a hell of a lot of cars a hell of a lot less efficient than those two, given production constraints.
This may be reason for even more panic, of course – since if gas DOES go up to $10/gallon in a couple of years, most people wouldn’t be driving something even as efficient as the current Prius, even if most automobile manufacturers got really serious about hybrids starting right now.
M1EK, I read GM-Volt, myself. I thought i had noticed some overlapping handles between GM-Volt and TTAC.
I see their topic of the day is pulled from the viability plan, “GM Plans to Produce Two Extended Range Electric Vehicles in Addition to the Volt in 2012.”
Whoa! Not just one nonexistent EREV but three! GM has clearly leapfrogged Toyota, again!
Never mind the insane assumptions and mind-boggling corporate welfare that make up the rest of the viability “plan,” two more imaginary vehicles is the big story of the day for GM-Volt.
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Anyway, I like the idea of less pure electric range, myself. And just for the reasons stated, the batttery’s the most expensive bit, might as well get full value from it.
I read, recently, that Toyota was thinking of 20 miles pure electric range as a sweet spot. Certainly, the vehicle would be far less costly.
And, of course, if one’s regular trips are closer to 20 miles than 40, the 40-mile vehicle is a crazy purchase. A 20-mile PHEV from Toyota will cut the legs out from under the market for the Volt.
Even a 20-mile PHEV is a pipe dream, as far as I can tell. You don’t want to only use 30-70% of a battery if you’re buying a much larger, much more expensive one, and even if they are going to use that same charge-band strategy, nobody’s put these lithium batteries through the same kind of testing that the NiMH batteries went through before they were unleashed in vast numbers on the US market (2004 Prius, technically the THIRD generation of the vehicle).
kgurnsey :
The average consumer barely understands a current hybrid, let alone advanced technology, so this does not surprise me.
It is still imperative that automanufacturers take the lead, and show the public what is possible.
Exactly. Real innovations don’t usually come from customer surveys – or we’d all still be using DOS and playing Pong. Hopefully there will be a battery size option on vehicles like the Volt (because I live 2 miles from my office) in the future, but real innovations come from designers solving the same problem from a different angle.
em>I wonder if the typical PHEV buyer understands that it’s the energy stored in the batteries that’s enabling the high mileage of their vehicle
Well, the drivers oughta’ , when they’re driving it as an electric vehicle.
Regarding plug-ins and mileage, even the existing Toyota Prius could be coaxed into higher mileage if Toyota would but issue software that could allow the battery to deplete to 40% before allowing the engine to maintain it at that level by supplementary charging in the same manner as the Volt is purported to do. In this case the battery would continue to accept all the recharge energy from regenerating braking action as before. Later on, when parked, a retrofitted vehicle could be plugged in and receive the approx 1.0 Kwhr needed to bring the battery back up to 90% charge, thus saving the road taxed fuel that is currently expended to do that job. But why stop there ?
All hybrids contain a 12 volt battery using the conventional lead-acid chemistry. Manufacturers still have to install them as lead-acid does not suffer from the self discharge characteristics of the more exotic power source of the main pack but interestingly they hold 0.9Kw-hr of energy. All that is necessary is to ensure that it can deplete to, and then be maintained at, 20% charge while driving and brought back to 100% full charge only by plugging in later. That’s another 0.8Kw-hr of road taxed fuel that would normally be required to have them fully charged.
You need to be aware that the average 12 volt lead acid battery has approx the same usable energy capacity as the more expensive high voltage NiMH battery. Skip over the italics if you will.
A typical $100 72A-hr 12 volt battery holds about 0.9Kw-hr of depletable energy compared to the $2400 NIMH Prius 1.3Kw-hr battery of which only 1.0Kw-hr is actually usable (for longevity reasons) as depletable energy. I am merely saying that installing an extra 45kg extra NiMH yields 1.0Kw-hr of energy (and 21kw of power which would double all electric performance).
On the other hand for 1/10th the price of NiMH, a pair of marine batteries could replace the existing 12volt battery and provide 2Kw-hr of online storage. This would bring the all electric range up to 10 miles from the 3 miles currently. Power in this case would be marginally increased to about 23Kw.
I have driven a Prius in electric mode but I am not sure how useful 9 miles at 42mph would be.
All it requires is Toyota to supply the minimal hardware needed and a few software patches to their code, however I won’t be redesigning the Prius in this post ! I’ll just say that this option is worth exploring by those who would otherwise seem to want to market large quantities of very expensive battery materials to uninformed buyers and it should be a simpler PHEV else perhaps someone can tell me how they intend to load share a pair of NiMH battery packs. I am all ears.
I know Robert prefers we avoid long discourses here so if any of the B&B want more info, I have thrashed some of this out already on the Edmunds.com site on the Hybrid Battery thread in their forums section where I occasionally hang out.
T2
If I were the lead engineer on a PHEV I would be figuring out how to make the battery packs modular, much like main memory capacity in a PC. Perhaps the baseline configuration is 4kWh of storage with optional additional packs in increments of 4kWh each up to a 16kWh maximum. Then, as battery technology improves, the battery packs might be upgrade to more capacity per sub-unit, again just like memory sticks in a computer.
Engineered this way, the car could be configured to meet the cost:capacity tradeoff which makes sense to the customer and it would be well prepared for at least one round of future upgrades if and when batteries get better and/or cheaper.
-John your idea won’t work, paralleling hi energy sources is extremely difficult, how do you get those incremental modules to share current ?
The only topology I can think of to do that would require each incremental pack to include its own up/down converter, but as you may know the Prius has integrated all its semiconductor power devices on to the same substrate.
That substrate is bonded to the “cold plate” which is located inside the liquid cooled inverter box. So if the present up/down conv is already included inside that compact heatsink assembly, where are you going to add yet another converter?
My own view is that unless we encounter $12/gallon gasoline, PHEVs remain a bad idea. More than that, it’s the sort of thing that displays lack of foresight in the vehicle powertrain industry right now.
The Volt scores over the Prius because it decouples the engine from the wheels, something that would have been possible more than 30 years ago with state-of-the-art semiconductors.
All that attention to “Bottom end torque”, “Turbo-lag” etc can now become a thing of the past.
Torque delivery is a task now transferred to Induction motors which can easily supply 300% rated torque even from rest, while at the other end of the speed range the lack of sliding parts allows them to hold 12,000rpm for long periods.
Now that Lutz is gone maybe someone at GM could take a closer look at the batteryless hybrid for the VOLT.
T2
Carmakers should get what they can on the roads as soon as possible. As the British radar pioneer Sir Robert Watson Watt said: “Give me the third best technology. The second best won’t be ready in time. The best will never be ready.”
That’s why I like Toyota’s approach. Get the Prius on the road. Improve it all the time. Never promise something too advanced until you are sure it will be ready when you say it will be.
GM’s approach with the Volt gives them a good challenge to shoot for. They are aiming to do what no one has ever done — put into wide production a range-extended, serial hybrid car that gets its power only from an electric motor.
But it’s like drawing three cards to fill an inside straight. The odds are against GM with the Volt. Big time.