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Water For gas a scam?

  1. Aug 19, 2008 #1
    Hi,

    I am not a student. I Have been searching the net trying to find good info and I thought this might be a good place to ask a question.

    I have been hearing a lot about a system you can hook to your car using water baking soda and your car battery to create hydrogen which is suppose to boost your mpg. It sounds like a scam to me.

    It has been a long time since physics and chemistry for me, but I remember a little. My main thought... You can only get out of a reaction what you put into a reaction. So this electrolisys contraption is powered by the battery which is powered by the motor. Which would mean that that the amount of energy produced would have to be less than what was used to create the energy because of friction etc.....

    Is my assumption correct....
     
  2. jcsd
  3. Aug 19, 2008 #2

    LowlyPion

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    Welcome to PF.

    This subject has been discussed a number of times here.

    This discussion link below was locked, but it touches on the very issues you are asking about.
    https://www.physicsforums.com/showthread.php?t=249170

    Conservation of energy has not been revoked as you seem inclined to already understand.
     
  4. Aug 19, 2008 #3
    thank you very much for your assistance sir. Trying to get a handle on science and math, but I will get it.
     
  5. Aug 19, 2008 #4

    CRGreathouse

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    You do remember enough to show that all of these systems are a scam. Good for you.
     
  6. Aug 20, 2008 #5

    uart

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    Yeah it sure sounds like a scam. The only other things that come to mind are

    1. If some "additive" promotes more complete combustion then it can of course give a small increase in mileage without violating any physical laws. Mind you the talk of numbers like 40% improvement in that other thread are way out of line with the small gain that might be possible due to increased combustion efficiency.

    2. You could cheat in a short duration trial by flattening your battery during the event, though it would be more efficient to use a surreptitious electric motor to boost the drive train. From a practical point of view this is of course completely useless
     
  7. Aug 20, 2008 #6

    uart

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    BTW this all reminds me of some snake oil fuel booster product that was recently exposed in here in Australia. This one was interesting because the scamsters appeared to have a lot of evidence that their system worked and were able to fool politicians to give them all sorts of grants to promote and export the product (which of course made it a bit of a political issue when it was exposed as a scam).

    It was quite a funny story in some ways, one of their "proofs" of the system particularly amused me. They took it over to India and convinced a local bus company to give it some critical trials. The bus company decided to fit it to one bus and trial it on the usual route and compare with their existing fuel consumption data. One of the scamsters boarded the bus as a passenger and gave the driver about $100 (or the equiv in local currency) and told him if he stopped and put in $10 of fuel "no questions asked" then he could keep the change. He did so and the company recorded almost $10 fuel saving on the route. This trial was touted as one of their most impressive proofs. Funny stuff.
     
  8. Aug 20, 2008 #7
    Your right with your assumptions. This is why many people say that such devices are a scam. However, I disagree based on personal experience. See the following thread for some good info and sources about this topic--pages 3 and up, starting at post #38, are the ones worth looking at.

    https://www.physicsforums.com/showthread.php?t=240385&page=3

    A key point that people fail to realize is that hydrogen supplementation modifies the combustion process. Hydrogen has a higher flame velocity than gasoline. Since hydrogen is also very diffusive, this leads to a faster burn of the combustion gases if sufficient hydrogen is input into the cylinder. A faster burn could cause the gases to expand much nearer TDC, which increases the overall work done by the combustion gases on the piston; work = force x distance. Hydrogen also causes a more complete burn of the gasoline as well, although most gasoline is burned during normal combustion conditions.

    I truly believe that beneficial results occur because somehow the device causes the engine to run leaner. I say this because I have observed my engine to run cooler with the device attached than without it, and this was observed over numerous times for the same car trip. A leaner engine has more air in the engine cylinders during combustion. Therefore, after the spark ignition, more heat from combustion is transferred to the gases rather than the cylinder walls, which is why the engine runs cooler and also why the thermal efficiency of the engine is increased.

    The question I have been trying to figure out lately is how the device can cause such engine conditions. I think that the sensors voltage measurements are affected somewhere, which causes the ECU to shorten the pulse-width for fuel injection--for example, in my vehicle the outflow from the electrolysis device just happens to be set up so that the ambient air temperature sensor is by-passed and the hotwire Mass-Air-Flow sensor is the first sensor in contact with the electrolysis gases, which include hydrogen, oxygen, and even steam. If this general hypothesis is true, then this explains why people, who only attach the device and who do not make car-leaning modifications, obtain negative or no results while others obtain positive results--the sensor setup and ECU algorithm to control fuel-injection pulse-width are likely to vary across manufacturers and car models. Of course, it is also possible that if an engine is lean then the O2 (lambda) sensor will detect excess oxygen in the gas and more gasoline will be added to even out the mixture.

    Many people make modifications to their car to obtain these lean engine conditions. A lean engine is proven to give better mileage, but does pose risks such as engine knocking and pre-ignition and increasing emissions. This is where hydrogen plays its most important role. It permits the engine to operate at these conditions without a large fear of such engine damaging risks and can reduce emissions below their normal values. This is proven over and over again in research articles from peer-reviewed academic journals. For example, researchers at MIT developed a plasmatron fuel converter that modifies a portion of the gasoline already on-board into hydrogen and use a turbocharger to obtain very lean conditions--note that the general and associated physics, such as thermodynamic laws and efficiency losses, are very similar to the ones used to supposedly "debunk" the electrolysis device.

    Don't settle on thermodynamic law as the simple and absolute explanation to refute this device, because as I have shown, this controversial topic is richer than what a lot of people suggest.
     
    Last edited: Aug 20, 2008
  9. Aug 20, 2008 #8

    russ_watters

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    I hadn't seen that thread before. Without double-checking the numbers myself, your post #65 gives a good calculation illustrating why the device can't improve performance at all, much less improve it by the 40% often claimed: replacing 1% of the gas with hydrogen to produce a 9% improvement in thermodynamic efficiency saves you almost enough energy to generate the hydrogen you need.

    You also made the classic mistake from the crackpot advertising claims early in the thread: you asserted that there is unused energy in the alternator. There isn't. You claim that alternators are self-sustaining (they don't require mechanical energy to continue to spin once started). They aren't. Getting 1kW out of a generator requires putting 1kW into it (assuming 100% efficiency).

    Please note: though that thread was reasonably scientific (though it started off bad and really should have been locked), threads of this type are on a very short leash due to the tendancy of the subject-matter to be crackpottery in nature. Scientific analysis/debunking is fine, but this isn't a "debunk my crackpot claims" forum.
     
    Last edited: Aug 20, 2008
  10. Aug 20, 2008 #9
    russ_waters,

    I have seen some of your posts in other threads. You have a keen scientific mind, but you are wrong in regards to this topic. Moreover, you have pulled specific comments, while neglecting others that were logically sound, from my previous posts in an attempt to discredit my knowledge on the subject. You are committing a large disservice to the members of the forum with your biased comments and reporting.

    I realize that I have made mistakes with previous posts and have used poor logic to explain why the device should work, such as the alternator idea that you refer to. However, I admitted my mistakes in my posts, and began to offer what everybody was asking for instead, scientific data that proves that the idea works. So, I shall do the same here by analyzing your previous arguments.

    From post #8 on the thread
    https://www.physicsforums.com/showthread.php?t=249170
    you said,
    Your statement and analysis on post #13 of the same thread suggests that this mysterious extra energy only comes from the combustion of hydrogen. This is a large misconception, but if this was all there were to how explain why it works, then you would be correct in saying that it is a violation of energy conservation. However, this is not the role of hydrogen.

    The role of hydrogen is to enhance and modify the combustion of the gasoline. Hydrogen has a flame velocity of 2.0 m/s relative to the 0.4 m/s flame velocity of gasoline and is extremely diffusive. So, when sufficient amounts of hydrogen are added to the combustion of gasoline, it has the following effects. First, the gasoline burns faster. This means that a smaller volume change occurs between the initial volume of the piston-cylinder system before combustion and the final volume after the combustion. Said another way, the gasoline burns closer to TDC (top dead center). This has the effect of increasing the work done on the piston, and thus increases thermal efficiency. Second, the chemical energy of the gasoline is released more homogeneously. This means that localized air charges with extreme temperature gradients between various small spaces in the engine are mitigated. The result here is an increase in the thermal efficiency.

    In this thread, you said
    Yes, according to the data presented, the device does not work when a 1% mass fraction of hydrogen relative to gasoline is used in the analysis. However, you completely misrepresented the essential point to take home from this post.

    The 1% mass fraction line on the plot was the smallest one that I could use in my analysis, so I offered some important ideas that readers should consider. First, it is impossible for standard 80 amp alternators to produce a 1% mass fraction, so ideally, this should not even have been used in the analysis. Second, based on the behavior of all of the mass fraction plots, if one assumes that mass fraction ratios lower than 1% mass fraction follow similar behavior, we would find that we have a net increase in energy. Yes, it is not significant, but it does prove that the device can work, if you take the assumption regarding the plots to be true. This is the important point that shatters the simplistic and absolute argument of energy conservation or thermodynamic law. Do note that this study was from 1989, and that it would be very unlikely that all cars would yield the same exact results, so the data from this study should not be used to make the assumption that 30% inefficiency increases are ludicrous. However, a 100-200% increase is ludicrous.

    Note that the graph from this post shows plots for lean engine conditions. This is the key to making the device work properly, since a lean engine is proven to yield MPG increases. The effects of hydrogen addition apply here as well. Another small effect would be a more complete combustion of the gasoline due to the extra air. I believe that I already explained in a previous post on this thread why hydrogen permits a vehicle to run under lean conditions. Many marketers of these electrolyzers do suggest that you modify your car to run lean. Now, some people have claimed to obtain positive results without these modifications, such as I, but this line of argument is a lot tougher to argue--I've stated a hypothesis in a previous post in this thread.

    Here is something else quite interesting. The National Hydrogen Association has as one of its members a Canadian company that markets and installs these water electrolyzers. The notables among the Board of Directors would not approve such garbage would they? Here is a description of the company article:
    http://www.hydrogenassociation.org/newsletter/ad101_canada.asp
    NHA members which includes the Canadian business:
    http://www.hydrogenassociation.org/about/members.asp?sort=2
    membership application which states that applicants must be approved by the board:
    http://www.hydrogenassociation.org/join/regApplication.pdf
    NHA Board of Directors:
    http://www.hydrogenassociation.org/about/board.asp

    It is important to think outside the box, rather than being hopelessly lost among the stars.
     
    Last edited: Aug 20, 2008
  11. Aug 21, 2008 #10

    russ_watters

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    I don't have time to go through that now, but I think I can, at least, articulate where the line is for me:

    Discussion of a scientific paper is ok.
    Unreferenced (scientific reference) of a crackpot claim is not.

    None of the scientific sources I've yet seen has suggested this process can break even, much less provide 30% (or whatever) improvement in overall efficiency. That makes any mention of a 30% improvement in efficiency a crackpot claim. And since you are providing many of the sources and claims, that makes your thought process very unscientific: you are still making the claim, despite posting scientific evidence that shows the claim is wrong.

    So that's the standard I'll be looking for: does any scientific reference actually say they see a potential for a significant improvement in overall efficiency?
     
    Last edited: Aug 21, 2008
  12. Aug 21, 2008 #11

    HallsofIvy

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    By the way, the gas a "baking soda" solution gives off is Carbon Dioxide, not hydrogen or oxygen and can not be used to produce energy.
     
  13. Aug 21, 2008 #12
    Your right. I have made around a 30% claim, which is based on personal experience. Readers can choose to determine the validity of this claim for themselves. Skepticism should persist because of the controversial nature of the topic, so your standard is very fair.

    However, if one looks at post #'s 48 and 63 on the thread, they will find another graph, which easily shows a value much closer to %30, if a 1% hydrogen mass fraction production via electrolysis is analyzed. Of course, the study was done on a test engine, so the argument can be made that the transformation of the results to an actual car engine may not be the same.

    Here is the graph
    https://www.physicsforums.com/attachment.php?attachmentid=14729&d=1216251641
    and the experimental setup and test engine specs
    https://www.physicsforums.com/attachment.php?attachmentid=14746&d=1216420235


    You have made a claim as well, which was proven to be inconsistent with the presented facts.

    So, where does this leave us? It should appear to any reader with little research on the topic that the idea is at least plausible, and that the idea may require experimental testing rather than armchair science, since cars and their parts associated with the operation of the device vary over a wide spectrum.
     
  14. Aug 21, 2008 #13
    This is not the role of baking soda either. Baking soda is to be used as an electrolyte to permit a greater current to exist between the electrodes submerged in water. Many other electrolytes can be used as well, such as KOH. The key with using electrolytes is to use one that is not thermodynamically favored to undergo chemical reactions more so than water. So, when choosing an electrolyte, one must look at the reduction potentials for each half-reaction. There are electrolytes that exist, and when used properly, they participate in virtually no reactions.

    The energy to make hydrogen and oxygen comes from the electrical input (ultimately, the gasoline) to the electrolyzer.
     
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