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Hydrogen generators

what do you guys think about installing hydrogen generators on old v8 engines? my son put one on his first car, 78 el camino, about 5 yrs ago. it seemed to significantly increase his mpg, for the short time he kept it functioning properly.

Hi Wesw:
Much has been written about hydrogen generators, both in these Car Talk archives, and throughout the web. The only benefit they have is to help line the seller’s pockets.

If your son observed any increase 5 years ago when he tried one, it was very likely due to the placebo effect.

Now, I have some land to sell, dirt cheap !

@wesw: These discussions crop up on here every so often. I guarantee you that these “snake oil” add ons for your car are absolute garbage, and a total scam. If your son thoughthe was getting better mileage, it was either the “placebo effect” or perhaps he tuned his car up at the same time he installed it, switched to a different brand of gas, was measuring his mileage in the summer vs. winter, or simply miscalculating his mileage.

Just looking at it scientifically, there is no way that these devices can produce a significant amount of hydrogen (if they are producing any at all), definitely not enough to even run a cigarette lighter, much less help your engine. There is no catalyst effect or similar either.

I’m feeling a bit lazy to Google it right now, but if you do some searching, you will find that the only results that tout any gains are from the scammers that sell these things or their shills. Many independent tests have been done on these and other gadgets that claim to improve mileage, and ALL of the tests have debunked them.

If you think about this logically, automakers are required to conform to increasingly stringent “CAFE” regulations that keep requiring more and more efforts to eke every last MPG out of a car. As a result we have louvers that close off airflow to your radiator, cars that shut themselves off at stoplights, air conditioning and alternators that shut off at times, and all sorts of gimmicky ways to steal every last mile possible. If the automakers are going to these extremes to get more miles per gallon out of cars, don’t you think if there was any merit to these “hydrogen generators” that they would be standard equipment on every new car? Sounds a lot simpler than all the tricky things that have been done already if it worked.

Now, I have some land to sell, dirt cheap !

Land??? I’ve got this Bridge in Brooklyn. Has a great view of the new World Trade Center too.

well, scientifically, when you run electricity thru H2O you get O2 and H2, right? so when you feed highly flammable hydrogen with an accelerant like oxygen into your carb it must have some effect on combustion? baking soda was also involved. if the car manufacturers made use of hydrogen, the safety precautions that would be mandated would likely be cost prohibitive. my son is something of a mechanical savant, much better than me truth be told, and he was sure he got significant results. apparently it was a pain to maintain tho,

Where do you plan to get this “free” electricity?

I’m 100% sure that your son did not get significant results.

Yep, no ‘free’ electricity, the power it takes to make the H2 far exceeds the power you get back by burning the H2.

If your son got significant results, it was because the installation corrected some other problem with the car.

Think of it this way: if a $50 kit could increase mpgs by ANY amount, why wouldn’t Autozone be selling them? Walmart? If you’re still wondering we can go into chapter and verse on how these things are scams.

I m pretty sure the electricity came from the same place as it did for all the other accessories. you must have done quite a bit of research to be 100% sure tho, so I will bow to your superior knowledge. (he said, tongue in cheek) but seriously, I read the credentials thread when I joined this sight, so I willtake everything(almost) you guys say seriously. by the way, why did the cred. thread get taken down. I would think that the info there would inspire the confidence of those asking questions here

Several years ago when gas prices spiked we got a number of posts by folks selling these things, so we went into lots of detail finding out and describing why they didn’t work. They were also tested by several different magazines, here’s one of the articles:

well, I read the article tex, and I have to say it was short on details and less than convincing. I believe my son reported about a 15% increase.

…it seems to me that the safety and liability issues would make it impossible to sell these devices

… I m not saying you guys are wrong, you just have not convinced me yet. I don t buy the no free electricity argument , our cars have numerous electrical loads, I don t see how running a bit of current thru water would make much difference

…I would think that the O2 alone could effect the combustion, no?

Every single watt that your car’s electrical devices use has to come from the alternator, which is driven by the engine. The more watts out, the more gas in. It’s really that simple.

…yeah tex, I get the electrical theory, I just am not convinced that a bit of current thru water would use many more watts than say, your radio. how much mileage do you lose by running the radio?

@wesw, the gas in the tank is run thru the engine (15% efficiency), the engine turns the alternator making electricity (60% efficiency), the H2 device makes hydrogen (at BEST 70% efficiency, a home made device, far less), the hydrogen displaces some of the need for gasoline that turns the alternator and drives the car.

At every step in the process of making H2, there are losses that came from the gas in the tank. The battery is not free energy, it must be replenished by the alternator. The losses in the alternator AND the losses in the creation of H2 mean there is less energy to feed to the car in the form of H2 gas than the gasoline used to make the H2. The ONLY way this works to improve mileage is IF there is a catalytic effect in the combustion of gasoline to run the engine and no proof of this exists in science.

Since an automotive engineer would give his left testicle to get another 15% in fuel economy. If this worked, they would be ALL over it to gain a competitive advantage over the engineers at their competitors that say it won’t work. Placebo effect only, sorry.

…what about the increase in combustion efficiency caused by the O2 that also is introduced?


…yeah tex, I get the electrical theory, I just am not convinced that a bit of current thru water would use many more watts than say, your radio.

On what scientific, peer-reviewed source do you base this assumption?

Running your radio uses gas, running anything electrical uses gas, with all the inefficiencies described by @Mustangman - so if you want to generate the equivalent energy of a gallon of gasoline from water as H2, you’ll need to use many gallons of gasoline to do it. If a H2 generator doesn’t use much electricity, it’s not generating much H2.

And more O2 doesn’t do anything, really. The car’s computer controls the amount of fuel added to match the amount of O2. More O2 would just mean more fuel burned, not some increase in efficiency.

But you not finding the article at the link convincing (along with all the other links in that article) tells me my explanations won’t do much, either.