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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?"
Oh, and here's the GM blog with the actual response.
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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.
I have a 2006 TDI Jetta, and (in practice) it gets 40 city/46 highway. The 2009 models are supposed to be even better.
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.
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.
There appear to be a few common myths being repeated here.
No, it isn't. Octane rating methodology is different. Read Octane Rating
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.
Diesel in Europe is cheaper than gasoline only because it gets vastly preferential tax treatment.
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.
End anonymous moderation and posting on
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."
Stale pastry is hollow succor to one who is bereft of ostrich.