I agree, but was intrigued by the irony because they are usually so anti-bama-volt focused. I am not proud...
I don't see an SUV on the top 10 list of best sellers in '11. There's the 2 trucks - F, Silverado (should be used for work, hauling, dangit), but the others are ..' Camry, Altima, Fusion, Corolla, Accord, Cruze, Sonata, and Civic. http://wot.motortrend.com/top-of-the-charts-the-best-selling-vehicles-of-2011-153551.html Not saying these 8 are all so efficient, but they all start pretty darn close to $20k price. Lowest seller of the 10, Civic is about 220k units in US for '11. Prius (family) came in a respectable 135k units, but there's much ground to make up. Prius family is the best strategy to get people into efficient cars and turned on to electric propulsion. If the long term ownership experience is good, they'll come back for more. We'll see how people deal with the repairs as Prius' get over 10 years old in large numbers. Will most buy another hybrid again after replacing batteries?
Prius c won't come too close to sales of liftback. c is 156" long car, Yaris 5 door-like. I'd wager about 3 or 4k / month of c here..
April can't come soon enough to get the real PiP vs. Volt sales battle going. Tell you one thing .... the 58" tall cat tower I brought home last night in Prius would not fit in a Volt ...
Dont be so sure it won't fit in a volt. The Volt's hatchback is bigger than many think. I've hauled 50 60"x40" poster board and their easels. My wife was sure it would never fit and we'd need her CUV but it fit with no problems.
Good thing you have a Prius. I couldn't imagine what a 58" tall cat would do if you weren't able to deliver a tower when needed. .
Ya know, I don't hate the Volt or anything, but I would have been a hell of a lot more intrigued if they had made basically a Prius copy, and somehow one-upped on a few things. That would have made me give a look, but still would have waited years for proven reliability.
I said I'd get back. Still don't have time to dig as deep as I'd like but since you provide no sources I had to go did some of my own. Before answering on your numbers let me note that I believe more important issue with every study if which I am aware, is that all these studies use the average US mix in bulk. In reality the PHEVs power is mostly being drawn down off-peak, and the proper computation would be to use marginal CO2 generation from off-peak loads. Off-peak there are more spinning reserves and idled plants (i.e. carbon being produced without electricity generated) and times when the wholesale price-per KW is zero or can actually become negative (because it costs to shut down their baseline loads so better to pay someone to use their eletricity) so marginal CO2 in those settings is far more important but also more difficult to estimate. (I've tried but don't feel my computations are publishable yet). So for now, like others, we'll just use the overall average. You said the CMU study.. so I'm guessing you mean Life Cycle Assessment of Greenhouse Gas Emissions from Plug-in Hybrid Vehicles: Implications for Policy Constantine Samaras and Kyle Meisterling Environmental Science & Technology 2008 42 (9), 3170-3176 Though your number's don't quite match up with that, it probably does not matter as that study, like just about every one I've seen, is based on GREET model for cars and some very generic estimates for the grid carbon impact, using data from back in 2004 or 2005. Since 2004 the US grid has gotten cleaner, and by 2009 the carbon intensity of Electricity generation had dropped to about 93% of what it was in 2004. (See EIA - U.S. Carbon Emissions in 2009: A Retrospective Review) While the CMU study uses GREET, which allocate CO2 from petroleum (and upstream costs) by product type, the CMU paper did their own estimation for electricity + upstream but did not do proper allocation for power plants. The base computation of carbon-production/kWh in that (and most papers) is improper because it does not account for the co-generation of heat/steam by the electricity industry in terms of energy produce but did include carbon from all fuel burned in the generation. The carbon needs to be allocated proportionally to the kWr and heating. The heating value of co-generation in the US is about 8% of the total output. Combining these correction factors, if you take your 670 * .93 * .92 you can estimate the current gCO2/kWh of 573. (That is Less than the 580 I mentioned earlier because the grid was even cleaner in 2009). If you plug the rest of your numbers using a updated grid CO2 estimation of 573 you'll get 222 for the Prius 234 for the Volt@70% 215 for the Volt @90% EV Of course if one is using green power, cleaner than the mix, then the Volt can be much cleaner. While I pay for wind power I'm not nieve enough to expect that its always green. From my reading and estimates (don't have the numbers to cite though) for CO wind-power the wind provides about 78% of the demand with the remaining 22% being gas or coal-backed plants. My estimate would put expected usage at about 150g/kwh for a "wind" powered, taking my expected production to 75gCO2/mile So while I don't agree with your actual numbers, I would agree with your conclusion that for the average volt driver, using EPA numbers and current grid electricity mix the Prius produces less Carbon. (I did not check other GHG). For a more EV oriented driver it can switch. However all the numbers are so close I'd say there is no statistically significant differences, they are within the margin of error of estimation and even minor changes in assumptions/numbers could make them swap ordering.
For your assumption of CMU, you are correct, couldn't find it in my computer so didn't cite the source. 573 gCO2/kWh is IMO a bit on the optimistic side... If I am not mistaken, the Volt driver (on average) is doing 67% EV per the publication, which gives him 237 gCO2/mile. Note that purposely I have not included 'US average mix' (as a vertical line) in the chart as: 1. This mix is changing in time. 2. Everybody can decide for his region (local grid) as long as he is not forgetting to include upstream emissions. 3. Keeping it "international". You did mention in one of your posts that the grid will get cleaner in the future, this is, of course correct, so does the transport sector. I am looking forward to add the PiP into the model.
Following up on the PHEV GHG discusion there was a nice talk by John Ward of US DOE at the SAE meeting, slides here http://www.sae.org/events/gim/presentations/2011/JacobWard.pdf It expanded on the CMU study which included a full Life Cycle Analysis model for PHEV and HEV comparison: And then ward adapted it using the 2005 eGrid data to state level reaching the following conclusion: Using 2005 (most recent) eGRID mixes, EVs/PHEVs emit less than: o HEVs in ~30 states, representing ~80% of the U.S. population o ICEVs in 48 states, representing 99% of the U.S. population More data in the following chart Note Life cycle analysis is a bit more involved than just operational GHG usage.
Of course. And Ward data (as well as CMU) are for general types of cars. Purposely I have concentrated in mine on operational GHG usage and on specific models, to keep it simple (can be checked by everyone) and interesting. Note that, for example, Ward is speaking of HEVs in general being 42 mpg cars while we know that Prius is 50 (at least by EPA).
Prius v is rated at 42 MPG. Volt purely running on electricity produces roughly the same greenhouse gas as the 42 MPG Prius v without plug. However, Volt runs on gasoline 1/3 of the miles on average, so Prius v as the edge.
Depends on what one calls the gen-1 Prius. According to The Birth of the Prius - March 6, 2006 Japan had them for years before we did. The first Prius, model NHW10, went on sale in December, 1997. and the sold that for 2+ years before the larger NHW11 models came to the US/EU. So the sales in the US were building on a pipeline with years of experience and the US got the second revision of the product. So either we got the second gen, or they had the first gen on sale for years before it came to US. Either way gwmort's comment about the sales choices made by Toyota was valid.
In other words, GM had even more experience with Volt. Between EV1, Two-Mode, and BAS, plus their fuel-cell prototypes, it's really hard to deny not already knowing lots about motor & battery development, support, and production. .
I agree, Capacity is bought. But if there is a premium and demand and models to track it, then it is much easier to justify green capacity rather than dirty. Coal is very cheap in CO (so close to WY mines, and I watch tons going by my house every day). When lobbying for the recent CO increase to 30% renewable, the actual numbers of people paying for green power was important. The state set a minum renewable standard precentage (RPS) of 10% goal by 2020 back in 2004 . In 2007 it was increased to 20% (2007) by 2020. Since the standards also define a maximum "2 percent rate cap price control" for the mandated green energy the producers have a bit of squeeze. The actual cost for green energy, especially installing new capacity, are usually more than 2% above the non-renewable costs. With that constraint, building capacity is very hard. The Voluntary Renewable Energy Credits (REC) help keep green power financially viable to build capacity rather than just buy credits from other states. (The state also has some odd credits for nameplate capacity installed in the state). In 2009 as we tried to raise it to 30% by 2020, lawmakers move it quickly after seeing the ease with which a lower target was met and the impact on CO's green energy jobs. One legislator (“Green 2.0,†State Legislatures, April 2009.) said In Colorado, the PUC defines a REC as “a contractual right to the full set of non-energy attributes, including any and all credits, benefits, emissions reductions, offsets, and allowances . . . directly attributable to a specific amount of electric energy generated from an eligible energy resource.†This definition implies that disaggregation of environmental attributes is not permitted in Colorado, so the PUC designates RECs designated non-solar (REC), (what i chose), solar (SREC), or on-site solar (SO-REC). Double-counting of RECs is specifically prohibited except to meet federal standards in the event that a federal RPS is enacted in addition to the state RPS. Colorado does allow unused REC credits to be applied to RPS for up to years, so if I pay for 60 blocks 6000kw and I only use 5000kw, they can credit the excess planned capacity to meeting the state RPS. You seem to disagree but I see increasing capacity as a 2 sided problem. Raising the required standards for green production, is one side. Having having customers buy in voluntary is a second support that helps them push for local capacity is a second. Together they have been, in my view, critical for our increasing greening of electricity. You can say its based on the market, to which I'll simply reply, guess what, paying a premium is part of "the market." And with the public buying in, its easier to get the regulatory statues. I do agree wind-blocks are not as good actually installing my own capacity (though wind is nice for the EV at night). Eventually I'll add PV, but I'm trying to push for a community solar garden so don't want to go roof top just yet.
In the discussion of GHG, the only way for the transport sector to improve is to raise fuel economy or to shift to a power source independent of the fuel. The latter is what plug in cars and electric railways have done. For the first, it is improving, but the Prius != hybrid. It's fuel economy is an outlier. It is nearly 20% than the next best hybrids (ex. Prius v, CT200h). It is the most common hybrid, but hybrids as a whole are still a small part of the fleet. Lifespan per until is also a factor. A diesel powered semi tractor can be on the road for over a decade easy. It's why so many dirty diesels are seen despite new emission regulations. The old ones are hard to kill. An old coal plant has an even longer lifespan, but there are options for reducing its GHG that aren't available to a moving power plant. We still need to see the final numbers, but with the PiP getting slightly less fuel economy than the Prius, I think the GHG numbers will be a wash.
