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Historically whenever gas prices have gone up, charlatans have come out of the woodwork offering drivers all manner of devices that are claimed to provide dramatic reductions in fuel consumption. From magnets that are clamped to fuel lines, to assorted vacuum advance devices, and intake vortex generators and magical carburetors none of these have actually been demonstrated to work. Many of these old school devices can still be found, but one of the most popular new devices is the on-board hydrogen generator and injection system.
The basic premise is that injecting hydrogen into the intake stream will displace some of the gasoline required, reducing both gasoline consumption and emissions. Just have hydrogen and injecting it will actually achieve this result since the hydrogen burns and produces only water and trace amounts of NOx (although much lower than gasoline or diesel engines). Burning more hydrogen means less gasoline is consumed. Easy right? Not so fast there buddy! Where does that hydrogen come from? The marketers out there are selling on-board hydrogen generators which are claimed to provide enough hydrogen to reduce gas consumption by 30-40 percent or more. Is this plausible? Not even close. Read on after the jump to find out why.

[Sources: Wikipedia, Hypertextbook.com, answers.com] Electrolysis of water is a process that's been known for over two centuries. It's not complicated, just stick a pair of electrodes into water and pass a current through them. Oxygen bubbles will be produced on one electrode and hydrogen on the other. Unfortunately as with all such processes it isn't 100 percent efficient. Some of the electrical energy put into the system is lost as heat. The process has gotten better over the years but it is still about 70 percent efficient at best.

If you convert 1 US gallon of water to hydrogen by electrolysis it will yield 420.6 g of hydrogen (H2 gas). If the electrolysis is 100% efficient it will take 16.821 kWh of electricity to crack 1 gallon of water. That 420 g of H2 only has an energy density of 14 kWh (33.3 kWh/kg * .4206). That's 16% more energy to crack the water than you get out of it. At 70 percent efficiency that means it would take about 24 kWh of input energy to produce hydrogen with 14 kWh of energy output.


To electrolyze water on the fly means the energy has to come from the engine via the alternator. Whatever electricity the alternator produces has to come from mechanical energy to drive it via the belt from the engine. That means the 24 kWh of energy will ultimately come from the engine while only 14 kWh will get put back in. As a result of this parasitic loss, on board hydrogen generation is an energy negative process that will actually reduce the total fuel efficiency of the vehicle because the load on the engine will be increased.

The only way that the fuel consumption of the vehicle can be reduced by hydrogen injection is to produce the hydrogen outside of the vehicle and store it as a gas on board. The total energy requirement doesn't change but off board generation opens up the possibility of using renewable sources like solar and wind to power the electrolysis.

With all of those companies selling on board electrolysis systems claiming to reduce fuel consumption there have even been news reports claiming these systems work. The answer to this is cheating. Ask any veteran NASCAR mechanic about places to store extra fuel on board a car. The same thing is being done by these scam artists. They are using stored hydrogen somewhere on board to make it seem as though their systems are beneficial.

Hydrogen injection is fine as a stop-gap but the hydrogen must be produced outside the vehicle. If home electrolysis systems or hydrogen filling stations are readily available, existing cars could fairly easily be retro-fitted with injection systems to reduce gasoline consumption. In India they are already experimenting with vehicles fueled by hythane (a blend of natural gas and hydrogen) but that is produced and sold that way.

The bottom line is don't waste your money on these devices. Want to save money and use less fuel? Drive less, consolidate trips, drive less aggressively.


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  • 172 Comments
      • 4 Months Ago
      Your article and premise that it takes 24 kWh of energy to produce fuel saving amounts of Hydrogen and Oxygen is seriously flawed if not a LIE. In fact it takes less than 5 watts of energy to run the common on the market jar Hydrogen Generator which is way less that the excess energy being produced by a cars alternator which is otherwise just wasted. Futhermore, if one of these generators caused any car to get just 5 more miles per gallon FOR FREE AND FROM WATER it would be well worth the $40 puchase of one of these units. Furthermore, people would not even have to be resorting to producing their own energy if the corrupt government now being ran by communist had not blocked America's massive energy reserves with their made up Global Warmong Scam being caused by man. Hydrogen is plentiful and completely clean and easy to produce, but it is free and can't easily be taxed or controlled and that is why the criminals who are currently in power running this country along with their criminal partners who write misleading articles like this one try to discourage the masses from taking their own initiatives and thus destiny into their own hands to save money. People we should be driving our cars for free and making our own electricity for our homes for free too, as the technology has been around for decades to do so, but the evil powers to be do not want you to know or even come close to knowing about it and how easy it is to produce. It can't be kept hidden for ever people. I build my own Hydrogen generators and I enjoy plenty of savings by way of extra gas miledge. I haven't bought one of the advertised ones, but they will work as well, because they all work on the same simple principle that the government DOES NOT want you to know about.
      • 4 Months Ago
      look at the name , an middle east name , sells us oil ya right !! when we coste or go down hill the energy is coming from gravity and still generating elect. . besides a very small amount of engine power is used to run the alternator. people who use this system say they picked up 3 to 9 mile per gallon by measurement of fuel used. so in real world it works no matter how you play with numbers to say it won't.
      • 4 Months Ago
      I love it when so called experts put up their opinion on a subject. If people listened to guys like these Edison wouldn't have invented the light bulb and the Wright Brothers wouldn't have flown. Just because you can explain what you think is happening doesn't explain what you don't know. There are unknown factors that are being overlooked by the author. There are experts in this field that have proven that it does work. Peer studies from universities that prove it works. This tech has gotten a bad rap because of so many back yard tinkerers thinking like the author of this article building faulty equipment that doesn't work and then selling it to the public. Stick with only the top companies offering this tech and do your homework.
      • 4 Months Ago
      The oil industry intends to take this lesson again from the public and quash it. Sometime in the future all gasoline will have hydrogen molecules attached to the carbon chains yielding better milage, less petrouem, and higher cost again.
      • 4 Months Ago
      Also faster cars are possible with pure/straight H2 kits (no O2 added method) etc if mass produced correctly still even?? Plus Ford combustion chambers are made for that method etc.
      • 4 Months Ago
      "I would also like to say that the point raised on the use of power from the alternator being an additional load is not valid, as far as i know, when the car is generating the current, if there is excess current a regulator limits the supply to the main system by basical disposing it. but when you drive at night that current is then utilised by the lights. Also the car does not change its mpg because of greater demand for current. "

      Moyo, you are incorrect. An alternator consists of a rotor and a stator. The current is generated by the copper coils in the rotor passing through the magnetic field generated within the stator. The stator's magnetic field is created by current passing through it. the stator's current is controlled by the regulator. There is no "excess current" to be "disposed" of in some magic manner. When the vehicle demands less output from the alternator, the regulator reduces the current in the stator and the alternator's output is reduced. Conversely, when demand is increased the regulator applies more current to the stator and the output increases.

      An alternator needs current input from the battery to function and is nothing but a whirlygig without that input.

      Further, though you can't feel the change in load on the engine when driving, I guarantee you it does happen. Increasing the input to the stator and thus the magnetic field will increase the "drag" on the rotor and require an increase in torque applied to the rotor via the drive belt and pulley. Example: If you were to offer to jump start a friends car whose battery is dead connect the jumper cables with your car at idle. You will hear the change in your engine's idle as the load on your alternator increases, and may see it on the tach as the RPM drops.

      I have my doubts about hydrogen generators but your entirely unscientific method "You don't press the pedal as deep as you would if it was not connected proving that it actully is improving the eficiency of the engine and saving fuel." does nothing to dispel them. Put the vehicle on a chassis dyno with a fuel flow meter in place and run a road load test with and without the device engaged. Your answer will be obvious and measured, not "seat of the pants".

      • 6 Years Ago
      You should state this as your opinion as you have definitely not fairly tested the product that you are reviewing.

      You are not alone in your views because many folks look at this the wrong way. It is not about the power of the HHO gas at all. It is about how it can make your gasoline burn better during a more critical time of your piston movement. (15 degrees after TDC. where the most power can be transferred to the crankshaft) Maybe you can understand how this works if you think of it as a supper 300 watt spark plug that makes your fuel burn more completely.
      • 4 Months Ago
      Not to be a jerk, but I found all the people posting that they have heard this works or seen it work, are new members; somehow I had a hunch would be the case, and somehow it was true. So, yeah...I'm definitely not convinced. I'll wait until a more recognized source actually confirms this produces some significantly improved fuel economy with neither higher emissions nor less performance (ie. the results are entirely b/c of the system not b/c of other adjustments that would have increased your fuel economy anyways without the system). I suggest the mainstream public do the same.
      • 6 Years Ago
      Good article. I agree that these are mostly scams, but you haven't disproven one of the claims I see made about HHO.

      Rather than displacing gasoline, the claim is that by injecting hydrogen, it is somehow changing the nature of the combustion process within the cylinder, resulting in more complete combustion or more energetic combustion, thus wasting less fuel or heat out the tailpipe. At a high level, the claim is that the parasitic loss of the hydrogen generator is offset by an increase in overall engine efficiency during acceleration (much like how a hybrid car's heavy batteries still help it achieve an overall higher efficiency in the city).

      That's the argument I've heard. As you've argued, at a thermodynamic level, HHO systems are fundamentally flawed. However, if they are increasing the efficiency of the engine, then they might have something to stand on. That said, all the articles I've read where a skeptic got it installed resulted in failure, so I imagine this is not the case.
        • 4 Months Ago
        If this system does not work why did my milage go from 29 to 41mpg? Now it's back to 33 but when I fool the air sensors it will go back up. Darn car makers!
      • 4 Months Ago
      just some comparisons to try and make some sence

      true, an ICE has verry low efficiency when used with gass ...
      this is due to the fact that gass just won't explode, the molecules ar too complicated
      the spark ignites the fuel so that it breaks down to usable gasses (smaller molecules) and after a "long" time of burning this stuff down its finally broken down into actual gass form witch can be exploded at around TDC (ignition timing takes care of this)

      with HHO this is not the case
      you can't get smaller than a hydrogen molecule, its the symplest molecule around, so no breakind down needed
      it has enormous explosive power, waaaay beyond you can fasm if you didn't play around with it and experemented with i.e. a symple reactor(2 iron rods in water) but with a bit of soap added [DO NOT DO THIS IN YOUR HOME]
      ignite the bigger bubbles and your ears will ring for days
      (i was stupid enuf to try this)
      if you try the same with normal gass from i.e. a gass burner (not an alcohol burner), you just get a big flame, not an explosion (ok.. if you call "pop" an explosion)

      anyways, since hydrogen is not working against its own combustion, the efficiency of this ICE suddenly becomes verry interesting
      95% is not uncommon for pure HHO ...
      with HHO added, you won't get anywhere near this high value since the "normal" fuel still has to be broken down, the HHO just makes it go faster

      for this reason i'm gonna go for 100% HHO, i allready found a place where i can get the protection for the engine parts but i like to see how it works before i do this since its kinda costly (ceramic layer on the pistons, the valves and the combustion chaimber)
      after the initial testing this will be done since you can earn it all back pretty fast (no more electricity bills)

      unfortunately for the car, i'm only alowed to add HHO since some law sais that the car isn't insured becouse its not running on the intended fuel (or something like that)
      but additives are alowed
      it is possible to get it tested on new fuel but that verry verry expensive (as far as i know)

      btw, burn power compared to explode power...
      if you just burn gass in an engine or next to a brick wall.. all you get is burning power, thats a bit of heat ...
      the engine will never run on something that just burns
      and a wall will never go down if something burns next to it

      now compress the gass and make it explode...
      the engine runs on exploding stuff in it, and a wall would definately go down
      same power ? i think not

      rambler
      • 4 Months Ago
      Hi folks,


      Yes I am new to the forum. I would like to say that I followed a NASA diagram for a vapor injection system. For about $10.00 I added a water bottle with an aquarium air stone and a plastic shutoff valve to my son’s car. With no other adjustments his mileage went from 31 mpg to 39 mpg the first week. He does not have a "light foot". In fact we often tease him about his NASCAR potential (heh heh). I have since found the same concept on many performance auto sites. Back in the 70's there was a device called the Gas Mizer. I laughed at it then only to find out now that it is common knowledge for many race enthusist. My neighbor who races dragsters has been using it for years. Apparently the water vapor causes the gas to burn smoother which is supposed to be the equivalent of higher octane prevenying premature detonation (knocking). My son says that his car runs smoother now and has more power.


      I have been researching the HHO generators. I believe that with a thorough examination of Stanley Meyer's generator many more of you may believe that a new process for generating H2 O2 may have been developed.

      1. His death was very suspicious.
      2. He did have government contracts to develop his system.
      3. He had just completed negotiations to acquire a huge tract of land for a research facility.
      4. His friends and neighbors support his cloak and dagger claims, he was often visited by men in limousines wearing turbans and robes, often shortly followed by Military vehicles.
      5. Many noteworthy individuals, scientist and professors have agreed that his devices worked.
      6. His patents were approved by actual testing and analysis.
      7. His conviction of fraud was a highly irregular and contested case and they never disproved his case.
      8. Many of the processes he described that were called bad science are now recognized as common knowledge (resonant cavities in microwave ovens, ionic wind, LC resonant circuits, etc...)
      9. His system does not violate any laws, he said so himself. He has simply developed a process for extracting energy from a source. Gasoline must be processed and refined before being used as a fuel. He claims to have found a way to refine H2O into H2 and O2 with a very low power input. Not electrolysis!


      Many scientist and inventors are ridiculed until there is a broad base of understanding to support their work.

      I don't need to understand all about electricity to use my toaster oven. I don't need to understand machine language programs to surf the internet. I don't have to understand organic chemistry to eat a good meal.

      There is an overwhelming amount of evidence to support the claim that HHO generators can improve mileage. I am constructing a unit now for further testing. If it works, great! If not....ok. For whatever reason it seems to be working for many people. What if they have found a true process but we just haven't discovered the actual mechanism and explanation for why it works. If it works (?) let's find out why! And share it with others.

      I have a friend who is an electrical engineer. He has one on his car and tested it on a vacation from Virginia to Ohio. He has an older Toyota Camry. His mileage almost doubled. I know him well. If it is working for him, I need to try it. He is no scammer. Just a regular guy who likes to experiment.

      By the way, I am a Mechanical Engineer with over 30 years experience and several degrees. I know that there are many phenomena that are odd and cannot be explained very well, like quantum physics and politics or my wife’s thinking process (smile).

      Please, let's keep an open mind and investigate the phenomena we may all be in for a pleasant surprise.

      After all remember this Quote by Albert Einstein?

      "There is not the slightest indication that [nuclear energy] will ever be obtainable. It would mean that the atom would have to be shattered at will. " "Atom Energy Hope is Spiked By Einstein / Efforts at Loosing Vast Force is Called Fruitless," Pittsburgh Post-Gazette (29 December 1934)


      Oops got a little carried away....

      Adi

        • 4 Months Ago
        Lets examine those Stan Meyer claims:
        - 1. His death was very suspicious.
        No. The coroner did a thorough examination, death was due to a ruptured cerebral aneurism - an artery swelled up and burst in his skull, the bleeding caused pressure and damage to his brain. It is a natural cause of death. Those claiming "poison" haven't examined the body, have done no toxicology tests, have no evidence whatsoever.
        - 2. He did have government contracts to develop his system.
        And your evidence is? Simply because he claimed he did? Scam artists like Meyers are known for their big lies.
        - 3. He had just completed negotiations to acquire a huge tract of land for a research facility.
        A "huge tract of land" isn't required for research. More likely, it was a way to invest all the loot.
        - 4. His friends and neighbors support his cloak and dagger claims, he was often visited by men in limousines wearing turbans and robes, often shortly followed by Military vehicles.
        Again, a big lie to promote the scam. Those "friends" could be shills, or the "visits" were staged. When Arab oil officials visit the US, they usually wear neatly tailored suits, not robes.
        - 5. Many noteworthy individuals, scientist and professors have agreed that his devices worked.
        "Worked" as in passing electricity through water makes hydrogen that can fuel an engine - but since it takes 14 TIMES THE TOTAL ENGINE POWER OUTPUT TO PRODUCE ENOUGH HYDROGEN TO RUN THE ENGINE, it cannot even run itself, let alone power a car. It didn't work as a "water powered car".
        - 6. His patents were approved by actual testing and analysis.
        That's not how the patent process works. The Patent Office does not require a working model except for "perpetual motion" devices, thus does no actual testing. The analysis is to see if someone else might have patented it, and see if the design appears to be functional. Practicality is not an issue. Meyers patent assumes a battery powering his electrolysis cell to fuel the engine, which technically would work for a short time until the battery ran down. At 7% efficiency, it's a really silly idea, but still potentially patentable. His patent application does not mention his claim that it is self-powering, as that would have caused a denial of patent.
        - 7. His conviction of fraud was a highly irregular and contested case and they never disproved his case.
        The fraud was that he took money from developers and customers with promises to deliver the devices, and he didn't deliver. It was his customers that brought the case, they got tired of his endless excuses, and he was convicted in an open court of law. It is a straightforward breach of contract. Meyers was the one that couldn't disprove the case.
        - 8. Many of the processes he described that were called bad science are now recognized as common knowledge (resonant cavities in microwave ovens, ionic wind, LC resonant circuits, etc...)
        Sorry, wrong again. Resonance has a long and well known history in science, it has NEVER been considered "bad science".
        - 9. His system does not violate any laws, he said so himself.
        You're taking the word of a convicted fraud?
        - He has simply developed a process for extracting energy from a source. Gasoline must be processed and refined before being used as a fuel. He claims to have found a way to refine H2O into H2 and O2 with a very low power input. Not electrolysis!
        Using an electrical current to split chemical bonds is "electrolysis", whether it is DC or pulsed DC or AC doesn't matter, it IS electrolysis. Refining oil is simply a process of separation of a mixture of already flammable substance, no chemical bonds need to be broken. Splitting water molecules is not a simple separation, the chemical bonds between H and O must be broken, and that takes a lot of energy, 14 times more energy than can be recovered by burning in an internal combustion engine. Meyers cell produced a large volume of gas with a low power input, but that is only because hydrogen is a very low density "lighter than air" gas. A full gallon of that "electrolysis gas", uncompressed, is the energy equivalent of just a droplet of gasoline.

        "Improving fuel economy" was not Meyers claim, he claimed to run without any fuel but water.
        The fuel economy improvements reported by HHO enthusiasts are due to reduced performance and the placebo effect.
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