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GM Cornered Into Defending the Volt

Al notes a story in Technology Review reporting on a CMU study (now over a month old) claiming that the Volt doesn't make economic sense, and GM's response. The study suggests that hybrids with large batteries offering up to 40 miles of range before an on-board generator kicks in simply cost too much for the gas savings to work out (PDF). Al writes: "Unsurprisingly, GM disputes the claims, saying 'Our battery team is already starting work on new concepts that will further decrease the cost of the Volt battery pack quite substantially in a second-generation Volt pack.' Interestingly, however, GM admits that the tax credits for plug-in hybrids will be crucial to making the volt successful. Without those credits, would an electric vehicle like the Volt be viable?"

15 of 769 comments (clear)

  1. They missed the Technology Review link by Anonymusing · · Score: 4, Informative

    They forgot the actual link.

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    1. Re:They missed the Technology Review link by Anonymusing · · Score: 5, Informative

      Oh, and here's the GM blog with the actual response.

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  2. Re:The economics of it.... by bgarland · · Score: 5, Informative

    You obviously don't value that the Prius is larger than a Corolla, more comfortable to ride in, and will probably last longer (based on the historical evidence of Prius so far).

    By the time a new 2009 Prius kicks the bucket (15 years at least), we'll see where gas prices are. I'm betting we'll be above $5/gallon before the end of 2010.

  3. Re:depends on price of gas? by Orne · · Score: 4, Informative

    Yes, and I bought one (a Toyota Prius). Of course I did that in Fall 2007 before the summer spike, because I value efficiency over origin.

    The problem is that today in PA, the price of gas (this afternoon) is $1.83/gal x (1.4086 pound / $) x (gal / 3.7854 L) = 0.68 GPB / L (you have a 33% markup in taxes over our taxes!) Dealers today have more Priuses on the lots than they know what to do with, because people won't pay the $28,000 price tag for a 40% increase in mpg. At current prices, it's cheaper to pay $12-15,000 for a compact car at 30 mpg and eat the difference in fuel.

    And that's what I see GM is up against. They are going to pop out a car that I'm sure will start at $30,000 for a compact car and go up to $40,000 with options (the gas/hybrid Prius MSRP is about $25,000 base). You won't have liquid fuel costs, since the fuel shows up on your electric bill, but it's still $0.0729/kW (that's from Exelon/PECO's web site for Residential rates). Wikipedia says that the Volt's battery capacity is 16 kWh, (wow, Wiki's cost estimates go from $35-40,000, only 30 with tax subsidies), with an effective use of 8.8 kWh. So, assuming you drive a full battery 6 days a week, 4 weeks a month, that's 6 x 4 x 8.8 x 0.0729 = $15.39/month to fuel a car, not bad! But what's harder to estimate is that your monthly loan payments are probably $300 higher... so that's where your gas savings go.

  4. Re:Doesn't Make Economic Sense by Phreakiture · · Score: 4, Informative

    Know also, that diesel fuel has a higher energy density than gasoline. A (US) gallon of gasoline has 125,000 BTU of energy, while a (US) gallon of diesel has just under 150,000 BTU. Keep this in mind when comparing the fuel economy of a diesel to that of a gasoline engine.

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  5. Re:Doesn't Make Economic Sense by clutchcargo · · Score: 5, Informative

    I have a 2006 TDI Jetta, and (in practice) it gets 40 city/46 highway. The 2009 models are supposed to be even better.

  6. Re:Doesn't Make Economic Sense by cabjf · · Score: 5, Informative

    Because diesel in the US is taxed higher than regular gasoline. Therefore, it won't make economic sense for someone to purchase a diesel engine vehicle in the US. Until the government changes that situation, diesel will remain a small niche in the consumer market.

  7. Re:Doesn't Make Economic Sense by DuckDodgers · · Score: 4, Informative

    1. US gasoline is lower octane than European gasoline. The Astra engine was detuned from its European spec to use the cheapest fuel here, because almost all Americans buying economy cars expect to use the default low octane fuel.

    2. GM, Ford, Honda, Toyota and Hyundai ALL sell diesel cars outside the US. Right now only Volkswagen and Mercedes offer diesel engine cars in the US because our diesel emission standards for non-commercial vehicles are very difficult to satisfy. If you're going to find the situation "offending", be offended by the automakers like Honda and Toyota who had plenty of resources to offer diesels in the US (unlike the domestic automakers) and still failed to do it.

  8. Re:Doesn't Make Economic Sense by jshark · · Score: 4, Informative

    Currently, in the US state in which I reside, diesel is $2.089/US gallon, gas (petrol for all you people who spell it "colour") is roughly $1.889/US gallon. Both prices include all applicable local, state, and federal taxes.

    My 2002 VW Beetle TDI w/ 150,000 miles on it gets an average of 45 miles on a US gallon of diesel. My wife's 2006 Beetle uses petrol and gets roughly 26 MPG.

    Doin' the math that's more than 70% better mileage for only 10% more money, or, to put it in a different light, I get around 630 miles per tank while she gets about 360, or, to put it another another way, diesel would have to cost almost twice as much as petrol before I started to lose money on the proposition.

    Oh, and since I run diesel my car is exempt from state emissions inspections where I live, thus saving another $30-40/year.

    So, how exactly does this *not* make economic sense?

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  9. plug-in prius being released in 2010 by chipace · · Score: 5, Informative

    I'm opting to buy a plug-in prius next year. It will be cheaper than the Volt, and most likely higher in reliability.

    At least I am seeing some return on my tax dollars, as the Volt has stimulated Toyota to keep their Lithium-ion plug-in on schedule.

  10. You mean kilometers per joule by George_Ou · · Score: 4, Informative

    Per kilogram of fuel is variable. It's distance traveled per unit of energy that matters.

  11. Re:Doesn't Make Economic Sense by Vindicator9000 · · Score: 4, Informative

    GM bought Opel in 1929 and Vauxhall in 1925. It wasn't like they just bought them out recently to acquire their new and exciting diesel technology. I believe that they are mostly designed in Europe though, by European GM engineers.

  12. Diesel myths and reasons for buying hybrids by hwyhobo · · Score: 5, Informative

    There appear to be a few common myths being repeated here.

    US gasoline is lower octane than European gasoline

    No, it isn't. Octane rating methodology is different. Read Octane Rating

    I would much rather have (some diesel vehicle) that gets this (some incredible number)

    1. Please make sure your are not quoting UK gallons - they are bigger than US gallons, and therefore get more miles.
    2. Please understand that fuel efficiency measurements in Europe are quite different than in the US. The 2008 US EPA measurement methodology is much more conservative.

    cheap (diesel)

    Diesel in Europe is cheaper than gasoline only because it gets vastly preferential tax treatment.

    We have some bizarre unxplained fear and loathing for diesel in the US

    It may have something to do with poor diesel history in the US, but also with health side effects. Even with ULSD, the nanoparticles are suspected contributors to pulmonary and cardiovascular diseases.

    BTW, I love diesels. I love driving them, I love the torque, I love increased fuel efficiency. However, it is important to know the whole story because the other side has very good points as well.

    As for hybrids and plug-in hybrids, yes, I will likely buy the new Honda Insight when it becomes available even if it costs more than a regular vehicle of the same kind, and even if I cannot recoup the extra price. I would rather pay more money for R&D into technology than drop coins into Al Qaida's collection box.

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  13. Re:Doesn't Make Economic Sense by maraist · · Score: 4, Informative

    US gasoline is lower octane than European gasoline.

    I don't understand why people keep saying this.. No they don't. They rate Octane differently than we do. They use Unloaded Octane reference engine values. The US uses (Loaded + Unloaded) / 2. Says so on every freaking gas pump in the US. There is typically a swing of 2 to 10 Octaine points between loaded and unloaded - thus the averaging allows for greater variability in synthetic blend possibilities while simultaneously giving a more accurate performance characteristic.

    http://en.wikipedia.org/wiki/Octane_rating

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  14. GIGO by Rei · · Score: 5, Informative

    And it's people like you that PHEVs are designed for.

    Once again, Slashdot does its best to continue ignorance by leaving out the core criticism of the study: that the study's authors assume a battery pack price of $1000 per kilowatt hour, and that's not even close to they cost today, let alone 5-10 years from now. And that's hardly their only mistake. I'll list their assumptions, and make a few quick comments on them:

    * A 2004 Prius with varying size packs
    * They upgrade the size of the motor to be sufficient to operate as series, but still keep the parallel configuration (why...?)
    * 52 kW motor (70hp), yet weighs 40kg (huh...? The Tesla Roadster does 185kW with a 31kg motor)
    * The main assumption that 1kg of batteries requires an additional 1kg of structure (Um.. really?). They also test 0kg and 2kg per 1kg of battery mass.
    * Li-ion (unspecified chemistry). 100Wh/mi -- similar to LiP and some spinels -- and a 25% packaging weight penalty (on top of the 1kg weight for every 1kg of batteries)
    * Only 50% depth of discharge (i.e., they're only using half of their pack)
    * Charging at $0.11/kWh (US residential average)
    * Gasoline at $3.00/gal (probably a reasonable long-term value)
    * Assumption of $1,000/kWh battery cost (Um, no. I can get Thunderskys at non-bulk rates for a fraction of that. I can almost get A123s at non-bulk rates for that. The Th!nk's pack is $500/kWh, and they think they can cut that in half with production rates of several hundred thousand per year. Conventional li-ion, like Tesla uses, is ~$300/kWh currently. In short... no.). They justify their number by pointing out that it's cheaper than the original price of the Prius's battery pack (ignoring that small HEV battery pack prices don't scale linearly to BEV or PHEV packs or linear with capacity in general)
    * GHG emissions of the grid are assumed to be fixed over time (Um, no)
    * Vehicle lifespan of 12 years (the average vehicle *on the road* today is nearly 10 years old, and that number is increasing, so... no)
    * 12,500 miles/year (reasonable)
    * Vehicle base purchase cost, excluding the battery pack, of $17,600
    * Assuming by default no carbon tax, both on electricity and gasoline, but considering it under alternative scenarios
    * No tax credits assumed
    * No battery replacement (in the base case; an alternative scenario includes replacement)
    * A 5% "consumer discount rate", No clue what that is, but they state that the higher it is, the less competitive PHEVs are. So it's some sort of penalty. (Perhaps purchase interest rate on the auto loan? If so, too expensive.)

    In short: stupid assumptions in, stupid results out. Note this paragraph that they just skim over:

    Cheap battery costs of $250 per kWh would significantly increase competitiveness of PHEVs, making them similar to or less expensive than HEVs and CVs across all distances driven between charges. A battery technology with an increased SOC swing, which would allow more of the battery's physical capacity to be used in operation, would also improve PHEV competitiveness, making moderate ranged PHEV20s cost competitive with the HEV and CV.

    In short: "If we pick more reasonable numbers, PHEVs are great. But with the bad numbers we picked, they're not."

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