When it comes to creating energy you can't make something out of nothing, says the BBC newsreader, from behind the very important desk. "Until now, because British scientists seem to have turned this fundamental law of physics upside down." The Mail on Sunday loved it too. "Amazing British invention creates MORE energy than you put into it - and could soon be warming your home," it said. Taste the excitement. "It violates almost every known law of physics."

Well, that'll teach those so-called scientists a lesson. The device is a heating element made by a company called Ecowatts, and it is claimed to make more heat energy than you put into it. Has anybody validated this claim?

"Jim Lyons, of the University of York, independently evaluated the system," says the Mail. Oh. He's a "business development manager" in York's enterprise and innovation office, although he does have a fun science hobby. "As a member of the British Society of Dowsers, he undertakes research into the geo- and bio-physics of Earth energies. His special research topic is the mechanism of dowsing, based on quantum ideas in consciousness studies."

I contacted a working scientist who was previously reported - in the Telegraph in 2003 - to have independently validated a similar device from the same company. He wishes to remain anonymous, because he is bored with getting long conspiracy theory emails from free-energy cranks, but he is now a leading electrochemistry researcher at a Russell Group university.

He was employed to do a single, very specific test, using measuring equipment provided by Ecowatts, and the conclusions in his report were very guarded: "Using the apparatus supplied by Gardner Watts and the procedures of analysis suggested by the company there appears [my italics] to be an energy gain in the system."

Using the apparatus provided, it's true, this scientist could get incredible results: the meters would read zero, and yet water would boil in around five minutes. Because the meters provided weren't working.

The problem stems from the difference between measuring alternating current and direct current. Stick with me, science is fun when you're making people look stupid. The meters he was given were to measure direct current: there was a diode in the circuit (this is a "one way street" for electricity), so theoretically the current could only flow one way, making it DC.

Unfortunately, at high voltages the special, magic free energy cell went into "oscillation": that meant that the current was alternating at high frequencies that were beyond the threshold of the diode, so beyond its ability to control the electrons.

Therefore the current could flow in both directions, therefore it was alternating current, and therefore the current measurement was invalid. I speculate that the "inventor" made the same mistake, and I can honestly say I find the little histories of these devices fascinating.

Anyway, in these tests, the investigator saw the current steadily increase with applied voltage and then fall to almost zero as the system went in to oscillation. An "energy gain, breaking the laws of physics," was only recorded when the system was oscillating in such a way that the measurement of "energy going in" simply became invalid.

So did our man try measuring the current properly? Yes, he did. He placed a magnetic choke on the system, which prevented the system going into oscillation and removed any energy gain, and also measured the (large) alternating current with his own meters in the circuit. No energy gain.

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