Still some definite hurdles, but those appear to be mostly regulatory rather than technological. The payback is pretty decent, as well. Even without the tax incentives, if gas got to $5/gallon and you're a large mileage driver (40K/year) and only get 20mpg, you'd save in the neighborhood of $6K the first year - assuming they get down to $2/gallon.

At $1/gallon, the savings for our large mileage driver is up to $8K.

Obviously scales down the more efficient you get and I've not taken into account the lower mpg that comes from ethanol (lower energy density, iirc). Nor does this address the changes that this would have on the sugar supply and it's impact on the climate, etc.

So, dunno if this is scalable to meet demand. My guess is that it's not something that could replace fuel consumption entirely - but it could put a small dent in it.

Damn those free market types for having the foresight to see things like this popping up everywhere. Wouldn't it just be much easier if we let our elites like Pelosi and the like just make some sweeping regulation to cover this?