Underhood hydrogen generator
 

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For those who don't want to/can't click on the article, the summary is that a man is currently working on a device that generates hydrogen and oxygen on demand and introduce them into the combustion chamber, drastically improving fuel economy and virtually eliminating toxic emissions.

Assuming it works as advertised, this has the potential to make a huge impact on the automotive industry. The two major issues with hydrogen in cars is production and storage and this device apparently sidesteps both problems neatly. The only potential problem I see is the supply of distilled water, but having to fill it only once every 80 hours of driving makes it much easier than it might otherwise be. Change your oil, fill the hydrogen generator.

I want one. Even if it doesn't work, it'd be worth trying.

Well... it sounds interesting, but I don't see how it can possibly work. The engine can't both create AND use the fuel - it needs an energy source. Thermodynamics tells us that we can't possibly get MORE energy out of the system than we put in.

OK, after reading more of the article... it isn't for hydrogen cars. His idea is meant to make existing cars more efficient by adding hydrogen to the combustion chamber, as well as reduce emissions. The energy source is still gasoline. So all it does is makes the more efficient. Unfortunately, that's not really the answer, but it is a step in the right direction.

Relevant quote:

This doesn't make any sense to me. First off I don't understand how this is going to reduce emissions of greenhouse gases. It's a cleaner burn, so what, carbon dioxide and water are still the main results of combustion, and I figured catalytic converters were already taking care of most of the results of imperfect combustion. It seems to me that this is simply reducing fuel consumption and the workload on the catalytic converter a nominal amount. As usual this is a newspaper article that is completely worthless for real scientific information. I would deduce that the presence of hydrogen helps by regulating the amount of oxygen available for combustion with the fuel.

Secondly, I'm not sure what kind of efficiency they're talking about, but the overall efficiency of heat engines is restricted by the second law of thermodynamics and is not something that can be substantially improved under the current universe's laws of physics. If they're talking about the proportion of fuel that goes to do useful work, then it may help by ensuring complete combustion, but the numbers still don't make sense: as far as I know the 35 percent figure quoted for current engines is the "heat engine efficiency" and it's impossible to get a heat engine efficiency of 97 percent. 97 percent sounds reasonable for the proportion of fuel properly combusted, but then I don't think current engines are nearly as bad as 35 percent in that department. Does anyone out there know what's the story with this?

Not that reducing fuel consumption and smog gases and saving the lives of catalytic converters is not a noble goal, but in my understanding this is not much of a solution to the problem that they're making it out to be.

The water and carbon dioxide are the ideal results of a complete combustion and are much less harmful than carbon monoxide and nitrous oxides. The catylytic converters help, but they don't eliminate the problem

I'm not 100% sure on the physics of it, but I've heard of it before.

It's pretty much impossible to get 97% thermal efficiency and even if it were it'd take more than a hopped up radiator.

The figures they're talking about is complete burn and incomplete burn. 35% of the fuel in your combustion chamber goes through the complete combustion process, resulting in nothing other than water and carbon dioxide. The other 65% is still burned, but incompletely, resulting in carbon monoxide, elemental carbon and nitrous oxides. This is the stuff that hurts the environment. This device, be it by increasing temperature, regulating the flame front, or just adding oxygen, promotes a more complete burn. That's what the 97% and 35% figures are referring to. Like I said, I'm not too sure on the physics of how, but the idea presented is entirely possible.

But I'm not currently buying this 35% figure if that is what they're talking about. I don't have any evidence or concrete knowledge, maybe someone does, but I would think the ratio of carbon dioxide and water to miscellaneous other substances in a modern car's exhaust is a lot higher than is implied if only 35% of the fuel is being completely burned. Really what I think happened here is the guy with the device referred to 97% as the proportion of fuel being properly combusted, then some reporter found the 35% thermal efficiency and reported the figures as referring to the same thing even though quite surely they're not. But I could be wrong.

And yes, oxides of nitrogen, carbon monoxide, unburnt fuel, etc., are certainly more harmful to the environment and to people than is carbon dioxide (which is of course why cars have catalytic converters), but carbon dioxide is still the main greenhouse gas everyone is worrying about and makes the article entirely wrong in its claim that this device would "solve the world's greenhouse gas emission problems".