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What resources does a vehicle use when it's sitting in a garage with the engine off? Or are you just talking about the resources used to build the thing, in which case where are your numbers?

at least two "car-share" programs for people who have occasional need of a car

The energy that goes into building a car outstrips, by far, the amount of gasoline you're going to burn during the 'normal' service life.

Despite all the data saying that hybrids do not create a net energy savings....

Unless your electricity is generated in a way that doesn't damage the environment you are simply moving the pollution from your car to the power station.

Yes - an electric car run from coal-produced electricity produces about the same amount of pollution over it's lifetime as a normal car - http://www.ilea.org/lcas/taharaetal2001.html

Wow, where to even begin. Right now there is a net reduction in CO2 emissions using dirty coal + BEV vs ICE. Read some of these reports, and then recheck your numbers: http://www.ilea.org/downloads/MazzaHammerschlag.pd f http://evworld.com/library/CanadaFuelCycle.pdf http://www.epri.com/event_attachments/2093_(16)Duv allEmissionsGlobal.pdf The benefit is not as large as you would like for current dirty coal, but it does exist now, and reduces our dependance on foreign oil. An existing BEV will actually get cleaner over time as dirty coal is replaced with something cleaner (like clean coal!). How much have we invested in oil wars over the last 20 years? Only roughly half of the power in the US is coal anyway, and of that not all is dirty coal. In california we have very clean power (primarily NG, nuclear, hydro and wind). EVs would make a huge difference in net pollution. There is a large unused off-peak capacity that would be sufficient until about 20-25% of all cars where electric. That would not happen over night, and gives plenty of time to upgrade the grid over 10-20 years as electric cars gain traction. We need to improve our electric grid anyway, so that is a good thing. I would much prefer investing in our electric grid than a whole new infrastructure for something else like hydrogen. BEVs are the ultimate flex-fuel vehicles, because they will run on the electricity produced by anything: Coal, NG, nuclear, solar, wind, bio. Whatever becomes viable in the future, your car could run using it. 100% flexibility. No foreign oil. Today. Current hybrids have it backwards, and at some point will change. The cars should be pure electric and then add a generator for extended range or off-grid use. Check out what Mitsubishi is doing (http://www.gizmag.com/go/4666/). Very cool stuff. If you are wondering whether electric works for semi trucks, just step up and see how a train works. The ultimate hybrid, and they do it the correct way (unlike the Prius), diesel generator powering electric drive.

The battery electric EV, charged from the electric power grid, makes much more sense. See
Carrying the Energy Future: Comparing Hydrogen and Electricity for Transmission, Storage and Transportation
for the detailed analysis.

Don't forget the manufacture of the entire hybrid propulsion system, not just the batteries. There have been quite a few "total environmental impact" studies on automobiles that suggest the actual operation of a vehicle is responsible for roughly half or less (depending on what's being measured) of vehicle's total impact on the environment (see here for an example: http://www.ilea.org/lcas/macleanlave1998.html). Considering some of the highly manufacturing intensive (large electric motors, batteries, etc) included in hybrid vehicles compared to a standard internal combustion engine, I'm not sure who would win out. Sure, if you compare a Prius vs. a Suburban I'm sure the hybrid would win hands down, but what about a hybrid vs non-hybrid Accord? Or a Prius vs. any number of the highly efficienct diesels that are sold everyday in Europe? Maybe hybrids aren't so green after all. I for one, am getting pretty tired of everyone praising Toyota as the be-all, end-all green auto manufacturer. For a company so green, they sure have spent a lot of money in the last decade trying to build more large, fuel thirsty trucks for the American market. Not to mention, their fullsize pickups and SUV's don't exactly take top honors for fuel economy compared to domestic vehicles either. (Check the fuel economy comparator at Edmunds.com - http://www.fueleconomy.gov/feg/sbs.htm) Just my $.02

Of course, a search on "car manufacture energy consumption" would have turned up this page which shows that manufacture accounts for about 10% of life-cycle energy; fuel accounts for nearly 75%.

(I can't believe someone rated you "Insightful".)

Just the opposite.

It is true that fuel contributes only a fraction of the total life-cycle energy of an automobile, but that fraction is more like 4/5. That's including "fuel cycle" energy (i.e. the energy needed to get the fuel from raw deposits into the tank) with fuel, since both decrease as mileage improves.

Here's an online reference that looks reputable, http://www.ilea.org/lcas/macleanlave1998.html.

As for the amount of energy to dispose of a car, my previous citation says

In all cases, they [MacLean and Lave] chose not to analyze environmental impacts from the recycling and disposal stage, because they agreed with earlier studies indicating that the environmental impacts of manufacture and use greatly outweighed those of disposal. They based their analysis on a 1990 Ford Taurus, assuming a vehicle lifetime of approximately 14 years and a fuel efficiency of 21.8 mpg.

I stand by my original observation that it's wrong to say that it costs more energy to replace a light truck with a hybrid car than it saves in using a hybrid car, but would still point out that that seems to me to be a straw man. In terms of actual choice when replacing a vehicle, then from an energy efficiency point of view, the hybrid wins. Whether it wins as compared to a high efficiency diesel is a moot point. As 9 million cars are replaced each year, along with 8 million trucks (SUVs & minivans are counted in this category), it seems that concentrating on halving the energy emissions of approximately 1/13th of the fleet would make a significant impact, along with encouraging end of life cars to be taken out of the economy slightly faster. When you consider that new cars are likely to be driven much higher mileages, then the figures look better still.

In short, it's not a magic bullet, but it's a good start.

The average US car drives 15000 miles per year, so, an SUV which gets 20 MPG would use 750 gallons of fuel per year. The Prius at 55 MPG would use 272 gallons a year, so it would take pretty much exactly 2 years or 30000 miles to save the entire manufacturing energy cost of the car, even with your unlikely assumption that the Prius was replacing a perfectly good vehicle that was being scrapped just to save energy. Replace a car which gets 35 MPG, it would take 6 years/90 000 miles to make a net energy advantage, which is still within its working lifetime, and obviously assumes that the car it replaces would last 6 years longer than it does.