My vehicle runs on at least three different fuels: carbohydrate, fat or protein. Of course, it does involve a little flexing on my part.

In Thailand, which has abundant natural gas reserves, gasoline-to-natural-gas engine conversions are available and very affordable to the average Thai citizen (which means it's cheap by our standards). I know of no such conversions available here in the US.

Several reasons occur to one offhand. For one reason, the type of flex fuel vehicle described doesn't exist. The ignition systems necessary to burn diesel, biodiesel or vegetable oil are so radically different from those of gasoline or ethanol burning cars that they can't be combined.

As for ethanol-gasoline models, they're a great idea in Brazil where every fueling station sells both, less so in America where ethanol is difficult or impossible to get. The best Americans can do at this point is an ethanol-gasoline mix. Even there, as has been pointed out in Salon, the use of ethanol increases food costs considerably, with little to no savings in carbon emissions resulting. Do Americans advocate starving an already stressed underclass in the developing world in order to fuel their automobiles?

LP-gasoline hybrids are a bit more practical. The major difficulties there are, given their availability in some other countries, solvable, but because of the necessity of having an lp system under pressure, the extra costs are considerable. Achievable, and probably the most practical and economical, so the lp-gas hybrid will most likely be the first one that Americans see.

In the end, though, hybrids are a dead end, simply because of the sheer amount of carbon that any type of hybrid fuel vehicle produces. The goal ought to be green electricity and new battery technology, to enable rapid recharging and greater capacity. Only new electric technology will really address the current problems. Switching from one carbon intensive fuel, like gasoline, to another, like ethanol, biodiesel or lp bottled gas, will help cope with rises in gasoline costs, but do nothing to address global warming. A huge investment in hybrid technology is a misguided attempt to solve one pressing issue, but does nothing to address the even greater one just down the road.

Hooray for Fiat, Toyota, and other other flex-fuel or other alternative fuel vehicle makers!

Your post cheered me as a hopeful sign of the fast-approaching new energy world.

But it saddened me, as well. America used to be the innovator of the world, the source of new ideas and inventions. Where are the Thomas Edisons of the 21st Century? Only in Europe and Japan?

We seem to be playing catch-up on too many new frontiers.

I'm number 74 on the waiting list for the new Chevy Volt, a promising new spin on electic and hybrid engines. And I'm excited about the prospect of this new driving adventure, but I also know that we need to be doing more.

We need to be exploring hybrids, and flex-fuel Fiats, and Chevy Volts and other options, now. While they are still options.

And while we still have options.

The domestic automakers started rolling out E85 ethanol flex fuel vehicles years ago and have sold millions of them. While E85 is available in the Midwest, activism by the oil industry and the Japanese automakers has largely prevented its distribution on the coasts.

Just Google 'flex fuel' or 'E85' to see for yourselves.

Many people don't even realize they are driving an E85 capable vehicle.

Just a thought really but don't you need CNG, LPG, Biodiesel, Cowshit, etc fueling stations? That trip to Kroger for a couple of Blue Rhino propane tanks is only to get you so far.

Automakers get extra CAFE credits for making them (so they can actually fall short of the standards). But the fuel just isn't available widely enough. And I think the CAFE credit is getting phased out at some point.

I was under the impression that a tax credit already existed. Or maybe it expired. At any rate, there are a bunch of bills to require more FFVs in the future (most recently reintroduced in the Senate by Lieberman and Roberts and in the House by Engel and Kingston)

I'm fairly certain Brazil provides huge subsidies/supports to kick-start their ethanol (from sugarcane I think) industry, which might explain why it is so much more widely available and why they can have cars that can run on gasoline or ethanol.

The one word answer is "Castro".

Sugarcane ethanol makes sense in Brazil, since it grows well and they have an integrated industry that powers the ethanol plants with the bagasse from the cane used as feedstock. But here in the US our sugar industry is heavily protected, with tariffs on sugar and a 54 cent/gallon tariff on incoming Brazilian ethanol. Why? The US sugar cane industry is concentrated in Florida, where the politically well-connected Fanjul family is the largest producer (now that US Sugar shut down) and has skillfully lobbied for price supports for decades. They're closely tied to the anti-Castro Cuban community, making them politically difficult to oppose.

In an economically rational world, we'd be importing tanker loads of Brazilian ethanol, which they'd be delighted to sell us, and using it in dual fuel cars. But not in this one.

I love all this flex fuel rhetoric. Ethanol is a fair fuel additive but a lousy fuel and you have to burn a lot more of it compared with an equivalent amount of gasoline. There's no way we can make enough of it anyway, and to overhaul our infrastructure to use it would be incredibly costly and a waste of money. Carmakers (especially GM) love calling ethanol green because it costs very little to make a car E85 compatible. It's huge step sideways though in terms of both environmental conservation and reducing oil dependency. It never hurts to make the car able to run on ETOH, but it is not an answer to anything. If you live in the midwest, OK, fine. But the rest of the country? No way.

What we need now is better public transportation infrastructure, and hybrids are a great answer until we get electric vehicles sorted out. Biodiesel, especially the stuff derived from wast oil products is also a real solution now that we have clean diesel technology. Older diesels do really nasty stuff to the air in terms of particulates especially.

There are a lot of people posting on this subject who don't have a clue what they're talking about, especially the author of the original piece. The oil companies and Japanese auto makers are stopping ethanol from reaching the coasts? That's hilarious. Brazil uses ethanol because they have so much sugar cane available, and it makes sense there. There are many other factors down there as well. We will be still very dependent on petroleum for many years; we need to do three things: conserve, conserve, conserve. Every city in this country need good light rail and it would create a lot of jobs as well.