It is difficult to effect deployment of high fuel efficiency vehicles. It is even more difficult to do it with incentives in a way that doesn't overly reward (encourage) poor solutions and under reward or penalize (discourage) better solutions. That's because, the designers of the incentives don't have the answers.

This is why high fuel economy mandate is so good a solution. It forces the people who can figure out how to, and who need to make the investments.... to actually put there efforts toward figuring it out and make the investments. They won't do it on their own, there's too much uncertainty. Target the end problem, higher fuel economy.

But fix the problems, like mandating one class of vehicle but not mandating larger, less fuel efficient vehicles. We need to use our brains to actually make it work, not play some political game.
Posted by: Kevin Hill

(April 14, 2006), that means at the pump -- if you were paying the full cost -- it would be $11.06 per gallon !

Riding my bicycle never felt so good......
Posted by: jim stACk

The good news is that technology is around the corner. The 94mpg 2008 Prius and the 150mpg Loremo can be converted to FFV (flexible fuel vehicle) capable of using also easily-produced -in-large-quantity renewable fuels such as hydrogen from solar and wind, and synfuel from gasification of biomass. Honda is producing home apparatus for compressing and fuel of natural gas and hydrogen. Until widespread filling stations will be available, each car can also carry a 3-5-gallon gasoline fuel tank for use in trips away from home. And let's not forget that advanced battery technology for PHEV is also around the corner.
Posted by: Roger Pham

But there's not much biomass, so eventually that will become in short supply. Well, if you have to, you can synthesize methane CH4 from electrolyzed hydrogen and CO2 (we have plenty of that around.)

Overall, if you have a plug-in hybrid (PHEV-20) running on renewable methane and electricity, you'd end up paying about $2 per gallon equivalent assuming ALL your energy came from $0.06 per kiloWatt-hr electricity. This is synthesizing methane from electrolyzed hydrogen. If you got it from biomass, it would be even less expensive.
Posted by: Jim Beyer

Well, Jim, I'm glad that we agree on the point that biomass conversion to methane will be a lot cheaper than ethanol conversiion. But, if additional hydrogen from solar or wind generator will be needed, then why not just add directly the hydrogen to the methane and call it Hythane (tm)? A detector in the fuel line of the engine can tell the percentage of each and adjust the mixture accordingly, on the fly. Running on renewable Hythane, your fuel bill might well be $1.3-1.5 per gallon equivalent instead of $2 USD, since no conversion from hydrogen to methane will be necessary.
Posted by: Roger Pham

I want to make an effort to say that we should not let the tyranny of small differences come between us. Hythane (tm) is also valid. I don't think the bill would change too much, as the bulk of the hit occurs with the electrolyzer. Conversion to methane is a 20% expense. Hmm, let's see if I can remember the numbers.

Assume 7 kw-hrs electric is the same as a gallon of gasoline. With charging efficiency, that costs you about 50 cents. A gallon equivalent of hydrogen is about 40 kw-hrs. Add in electrolyzer efficiency and methanation, you come up with about 70 kw-hrs of electricty needed (yikes!) or about $4.20 per galllon-equivalent. But not to worry, you only use the fuel about 20% of the time.

So the net (mixed) cost is (.5x.8)+(4.2x.2) = .4 + .84 = $1.25. Hey! There's even 75 cents let to pay for electrolyzer, etc. Really not so bad, huh?

A downside is amortizing the cost of batteries, but there is some hope in that department too.

So methane or hythane, there's probably a way out. I'd say use hydrogen if you are going to use it within a week, after that, better off making methane. How's that for a compromise, Roger?
Posted by: Jim Beyer