

Chevrolet Equinox fuel cell vehicle  (Source: DailyTech)
New catalyst is 2000 times more tolerant of carbon monoxide






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RE: Hydrogen derived from hydrocarbons....
By Solandri on 8/3/2010 4:29:04 PM , Rating: 5
This is correct. Burning petroleum in a combustion engine, you're limited by the Carnot efficiency. The maximum energy you can extract is 1 - Tc/Th where Tc is the cold temperature of your heat sink (usually the air for cars), and Th is the high temperature of your engine. For most automobile applications, this puts you around 30% engine efficiency. That is, 30% of the energy in the fuel goes into doing work, the other 70% just creates waste heat.

Fuel cells bypass this by converting the energy directly to electricity instead. They can frequently achieve 60% efficiency, with some fuel cells in the lab hitting over 80% efficiency.

By Etsp on 8/4/2010 3:39:49 AM , Rating: 2
There are some caveats to that as well... That formula assumes that the cooling system itself does not produce energy. Which is true in the vast majority of cases. However, there are means to derive electrical or kinetic energy that also act to cool the engine.

Two examples would be water injection, and peltier plates. Granted, these two methods aren't used much at all, but that doesn't mean there aren't ways to improve the efficiency of an ICE beyond that temperature difference barrier. It would require innovation on the cooling systems, but it's very possible. As far as how practical this is... well, at least it's more practical than some ideas being subsidized.

