Free Energy Debunking
High voltage and amateur science have long been uneasy bedfellows of pseudoscience and free energy. 4hv.org, like the rest of mainstream science, deliberately takes a very skeptical stance on free energy. This article will take a quick and very cynical look at a few of the most common quackeries floating around the Internet, without naming any names in particular.
These are devices claimed by their inventors to be perpetual motion machines of the second kind. Typically, they are electric or electromechanical devices that take a steady flow of electrical input, and convert it to pulses before feeding it to a load. Pulsed electrical current is difficult to measure accurately, so if you place voltage and current meters on the inputs and outputs of the apparatus, it's quite possible to fool the meters into saying that more power is coming out than what is going in. The inventor then goes on to reason that if the electrical output of the machine were fed back to the input, it would become a perpetual motion machine, and maybe even generate surplus electrical power.
Some people build complex and beautifully crafted examples of these machines, that include flywheels, generators, spark gaps and rechargeable batteries to cloud the issue even further. But the fact of the matter is that there is no evidence that anyone has ever got one to exhibit perpetual motion of the first kind, let alone "over-unity" behaviour. Still, they keep trying. One "over-unity" enthusiast once said that he had improved his machine from 75% to 90% efficiency, so he was confident that 110% wouldn't be far off.
An afternoon with a Kill-A-Watt meter, or a digital sampling oscilloscope and Matlab, would suffice to do away with the simpler examples of these machines. But once batteries are involved, things get more complex. Batteries contain surprising amounts of energy and can run a small machine for a very long time indeed. The Oxford Electric Bell has been ringing since 1840 powered by dry batteries, so many scientists in the 20th century would have been born and died while it was ringing, and hence would have no evidence that it was anything but a perpetual motion machine. But no scientist considers it to be one.
The way to debunk an "Over-unity" device including batteries is to try and induce it to give out more energy than the batteries can possibly contain. You can estimate this from the weight of the batteries and some chemistry. Remember not to go round to the inventor's lab for testing, as he may have sneaked hidden wires into the device. Have him mail it to you, and search the postman for extension cords ;-) Again, there is no evidence that any device has passed this test.
These are devices claimed by their inventors to overcome the force of gravity, cause objects to levitate, etc. The inventors often believe that electric fields interact with gravity, and hence their devices tend to be based on odd-shaped capacitors charged to high voltages.
There is a grain of truth in this, since electric fields do generate mechanical forces, as anyone knows who ever rubbed party balloons on a wool sweater and stuck them to the ceiling, or did the pie plate and Van De Graaff experiment. These electrostatic forces can be remarkably strong, and it is possible to build electrostatic motors that generate sizeable fractions of a horsepower. (Think of a Van De Graaf backwards.)
Electric fields also ionize gases, and the electrostatic forces then cause the ions to move. This generates thrust just like a jet or rocket engine. This is how the "lifters" often built by hobbyists work, and they often work remarkably well. Ion engines on spacecraft work like this too, although they have to carry gas to ionize, since outer space has no gas in it.
However, there is no evidence for any effects outside of the two explained above. Electric fields do not warp the space-time continuum and cancel gravity, or whatever. Lifters would not work outside of the atmosphere, unless they were converted to ion engines, which has already been done. Websites that show sleek lifter-powered craft soaring to the far reaches of the solar system are pretty much science fiction.
The car that "ran on water"
A few years back, an inventor claimed to have made a car that was powered by tap water. We'll finish by having a look at this claim.
First of all, is water a fuel? Simple chemistry suggests not. Water is hydrogen oxide: what you get when you burn hydrogen and oxygen. So from a chemist's perspective, it's already been burnt once and won't burn again. (Leaving nuclear fusion out of it for now.)
The plans for this car were in fact published, and it turned out that it used a gas generator that burned aluminium wire under water with an electric arc. Now, aluminium is a fuel, and it will burn under water, turning into aluminium oxide and hydrogen gas, which could be used by the engine.
So, the car didn't run off water. It ran off aluminium. Bcause aluminium is refined electrolytically, the energy released by burning the aluminium came from electricity, so it was really just a very inefficient electric car. And that assumes you took the aluminium oxide back to be refined again.
The inventor mysteriously disappeared, and one can only assume that he took a lot of investors' money with him. There are many exciting alternative fuels for automobiles, but this was not one of them.