Rants, rambles, news and notes from another geek

Water for Gas and the First Law of Thermodynamics

snake-oil I’m always amazed at the things people will believe. Today I got trackback spam from a “water for gas” site on my miles per gallon post. (The trackback has since been deleted.)

I hadn’t run across this particular “technology” yet, so I dug into it a bit. It turns out there are dozens of sites out there claiming you can add a water-based fuel system to your car to significantly improve your gas mileage.

The gist of what they’re claiming is simple:

  1. You use energy from your car’s electrical system to electrolyze water into Hydrogen and Oxygen.
  2. You then run the gaseous hydrogen and oxygen back into your intake manifold where it burns in your engine’s combustion chamber, resulting in more power with less gasoline used.

Sound oh so simple. Except that this is yet another instance of someone peddling a perpetual motion machine.

Here’s the problem: The first law of thermodynamics states:

The increase in the internal energy of a system is equal to the amount of energy added by heating the system, minus the amount lost as a result of the work done by the system on its surroundings

In layman’s terms, this means you can’t get something for nothing. Applying that to the water for gas system, it basically means you will use more energy electrolyzing the water into hydrogen and oxygen than you will get combining them back together when you burn them in your engine.

**In other words, if you took the gasoline completely out of the equation, you would eventually have your battery die because the engine wouldn’t make as much energy as it produced. **(See this breakdown of the math if you want more info.)

What is more interesting than the bunk science displayed here is the willingness of people to be duped by this and respond with things like “but my friend has one and it works great”. Here we have some guy in middle-America (with little or no scientific or engineering experience and certainly without any of the proper equipment necessary to actually test this) telling you that the last 200 years of science and engineering are false and that perpetual motion (or snake oil) are real. The fact is, most of these scams are actually MLMs and Pyramid Schemes, do I guess we shouldn’t be surprised at the misleading information.

Remember people: If something seems too good to be true, it almost always is! The ultimate test for this in on, however. Bruce Simpson has offered up a million dollars to the first person who can prove it works. Read more over at the One Million Dollar HHO Challenge site. (He’s got a bunch of other great links to the real science involved here in case you want more info.)

So thanks to the trackback guy for letting me learn a bit about this new form of Snake Oil. Hopefully this will help a few more people save their money for things that actually will save money on fuel, like cars that get better mileage.