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Larsen RADAX Hydrogen Internal Combustion Engine Video

While doing a little searching on the Internet for hydrogen engines, I stumbled across a video of the Larsen RADAX (Radial and Axel) hydrogen internal combustion engine (ICE) that I thought would be of interest to the inventors in the crowd.

The hydrogen engine was invented by Mel Larsen and has been reviewed by the American Hydrogen Association Northwest. Mel Larsen has claimed that his Larsen RADAX engine has set the word record for in thermal efficiency for an engine. The Larsen RADAX is an 8-cylinder, 2-stroke, 300 hp ICE that has an efficiency range of 45 – 54 percent, which far exceeds the 20 – 30 percent efficiency of a standard gasoline engine.

About Hydro Kevin Kantola

Hydro Kevin Kantola
I'm a hydrogen car blogger, editor and publisher interested in documenting the history and the progression of hydrogen cars, vehicles and infrastructure worldwide.

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  1. This seems to be an incredible piece of machinery, why is’nt in vehicles already. is it a real possibility to be in the equipment of now or the future, if so how far off and what is the cost comparison between it and other internal combustion engines?

  2. Unfortunately the engine no longer exists in free hands and is no doubt ensconced in some black lab being carefully dissected for its secrets. This is a very discouraging story, but it needs to be told. Mel Larson died about a year ago now. In his last days he was quite ill and was in the hospital. One night someone or some corporation’s henchmen broke into Mel’s workshop and with hoists and a truck stole his prototype engine and other equipment. This was a man’s lifework and it was callously ripped from him, as he lay seriously ill. No doubt this was the final straw in the life of the very talented inventor and engineer. He was no doubt devastated by the loss because he died a few days after the burglary. May those SOB’s get their just cosmic reward one day. Mel, we will carry on your work despite this sordid insult to your legacy.

  3. given the resources i am confident i could reproduce the prototype


  5. They’ll get what’s coming to them, and they’ll be exposed once something similar is out on the market.

  6. really?! that is awesome! What did you use for the cylinders??

  7. I believe I have found Mr Larsen engine in Dubai under a company call AVEC. The engine is featured combined with two 100 kw generators on our web site

  8. This article is four years old. Where is Mel Larsen now and where is his motor? HMMMMMM?????

  9. After Watching the video on the “” website I became concerned about one important point…They wish to sell the hydrogen for a engine that can run off of water. instead of creating its own hydrogen from water they want to continue to milk money from people by selling the hydrogen.

    This makes absolutely no since at all. Why would i want to buy fuel for something that can make its own. If my car can convert its own fuel and I am not forced to buy fuel whats the point in the whole thing.

  10. This is not the AVEC engine nor is is a swash plate engine as one utube viewer suggested. A lot of engines have common design aspects but what sets them apart is the sum of the ideas that are put together into a particular design. I have been investigating efficient ICE engines for over 20 years as a hobby and I can tell you this engine has almost all the major design elements that I would put in my own super efficient engine (if I had the means to build it). The science is all good on this and the man was a true genius to be able to conceive of and build this engine.

    The thing to learn about this is that the information to make more efficient engines is well known and has been for years. If you look at the math and find what represents losses and then try to minimize them then you will gain efficiency. That is what Larsen did and he did it well. But he wasn’t the only one who can. People with the money need to connect with the people who know the math and people who have the skills to build such engines so that they can become available. Large corporations will only release new ideas a piece at a time so as to preserve their future market share, at best. At worst they will just sit on it if it is a technology that will hurt their bread and butter business. Small businesses are the only hope to save the economy and the environment.

  11. N.J. – The hydrogen has to be separated from the H20 (water) and that takes energy. An engine that can produce it’s own fuel and have power output is called a perpetual motion machine and is considered mythical. The attainable goal here is efficiency gains.

  12. the only reason it was considered myth, the perpetual motion machine, is because of lack of knowledge. Hydrogen has existed, way before man did. And Tesla,
    gave the basics to do this with. Today, it is reality.
    BUT, Greed of men, stop the production.
    They may even be responsible for causing the 9.0 quake in Japan.

  13. Hydrogen fuel is the future of global energy demands. The problem is not in the production of hydrogen in the vehicle itself. Plenty of hydrogen can be produced at home to fuel the vehicle. The sticking point is storage. Gas vs. liquid. There have been breakthroughs in low pressure H2 gas storage in hydride tanks that can be safely stored in the vehicle.

  14. A very interesting point tim brings up, but storage of hydrogen is very easy, with lithium-6 deuteride. Too bad this is a ban substance because of its minor use in the making of nuculear wepons. Goverment regulated.

    Bob lazar has a eye opening video on youtube about how he converted his corvette into a running hydrogen vechile. he uses the hydride method because he has his own particle accelerator and is able to produce the substance under a licens agreement with the goverment.
    check it out

  15. How would you guys feel about prototyping my Rocket Hydra Engine/Hydrogen Rocket Body Pack Engine? Here is my link on Peswiki feel free to add me on FaceBook Too all the links are on my Peswiki page here

    My engine is over unity and completely self powered. If indeed your engine is not over unity and free energy, it is probably because Hydrogen and Oxygen gas are more spongy and less ridged than the exhaust gases of gasoline and diesel. So when you get your power stroke the gases are becoming repressed inside the cylinders making a loss. The HHO in my engine cannot be repressed because it just escapes. My engine also has fewer friction points than piston engines and a longer lever attached to the crank. Regular engines have about 6 to 10 inches of lever, mine has 12. These are things to consider if you choose to invest in me. Not to mention you wouldn’t ever actually need to manufacture and sell my engines because residual incomes can be had from energy buy back programs in many states. My state pays 2 cents per kilowatt hour and my engine will power a 40 kilowatt generator at 75% throttle, that’s over $800 an hour or about $500,000 a month. Get it in gear guys? Also my power stoke is constant unlike your piston style engine.

    Sincerely, Jesse Denson
    find me on FaceBook?

  16. WEll, now we have more than one to deal with, for Tesla is on the move. Their idea is starting the Worlds Largest Battery Factory. Reno… So, they will be having the mode for electric engines, as in the Tesla Car. However, what is the ticket is, to get them to accept the Electrolysis process to put onboard, using the new tecnology for the 10 times the size smaller batteries, and use that to make fuel to fuel the Cells that power the vehicle. Right now, they are with the dual engine in the car. Part Gas, Part Battery. We hope to persuade them on this, so that the vehicle will actually power itself, with no need to refuel anything. Now, there is a bunch in Germany, that has already made a car that runs on air pressure. So we have the hydrogen engine here, the dual engine at, and an air car somewhere in Germany. Lets organize the whole thing folks, so we never have to depend on oil ever again.

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