In which the press and the government prove they don't understand scientific basics

[unixronin]

ERIE, Pa. - An Erie cancer researcher has found a way to burn salt water, a novel invention that is being touted by one chemist as the "most remarkable" water science discovery in a century.

John Kanzius happened upon the discovery accidentally when he tried to desalinate seawater with a radio-frequency generator he developed to treat cancer.  He discovered that as long as the salt water was exposed to the radio frequencies, it would burn.

[...]

The radio frequencies act to weaken the bonds between the elements that make up salt water, releasing the hydrogen, Roy said.  Once ignited, the hydrogen will burn as long as it is exposed to the frequencies, he said.

[...]

Roy will meet this week with officials from the Department of Energy and the Department of Defense to try to obtain research funding.

The scientists want to find out whether the energy output from the burning hydrogen — which reached a heat of more than 3,000 degrees Fahrenheit — would be enough to power a car or other heavy machinery.

OK.  Who else sees the beginner-obvious problem with this "discovery"?

Hint:  The Laws of Thermodynamics.

This is, of course, beyond both the AP and the government bureaucracy.

Comments

[unixronin.livejournal.com]

It's really not the water that's the issue. And your water supply doesn't need to be salt water — you can re-use the salt, just add new water as you electrolyze it. (That's all this really is, just a different method of electrolysis using RF energy instead of direct electrical current.) The issue, really, is that you're not gaining any energy — all you're doing is electrolyzing water, leaving you with hydrogen gas that's rather more difficult to store and transport than it would be to just use the electrical energy that you electrolyzed it with for power instead in the first place. Whether you supply it directly as current or as RF, it takes a certain amount of energy to break the hydrogen-oxygen bonds, and you're always going to have to put at least that much energy in to break them, and you're only ever going to get at most that much energy back out by recombining them. The only thing it's really adding is conversion losses.

GM is experimenting with fuel cells and high-pressure hydrogen storage tanks in its Hy-Wire (http://auto.howstuffworks.com/hy-wire.htm) project, which has a stack of 200 fuel cells running off three carbon-composite high-pressure hydrogen tanks buried inside the "skateboard" and producing 124 kilowatts peak power, 94 kilowatts sustained. The Hy-Wire does a good job of illustrating the problem. The Hy-Wire's tanks weigh 165lb, but hold just 4.5lb of hydrogen compressed to 5,000psi (350 bar). GM is hoping to double that to 10,000psi in future versions, to increase range.

GM is being pretty cagey about what the vehicle's current range is, but we can do a back-of-the envelope calculation. The calorific value of hydrogen is 150 kJ/g, three times that of gasoline (http://home.att.net/~cat6a/fuels-VII.htm), so that 4.5lb of hydrogen is the energy equivalent of 13.5lb of gasoline ... which, at 737.22 kg/m³, or about 6.15 pounds per gallon (http://en.wikipedia.org/wiki/Gasoline), is just barely less than 2.2 gallons. A vehicle the size of a minivan doesn't go far on 2.2 gallons of gas. On most vehicles, that's about when the "low fuel" light comes on. Granted, fuel cells are more efficient than IC, but I'd still be surprised if the Hy-Wire's range to empty is much over a hundred miles, and very surprised if it's over 120.

(Compressing that 4.5 pounds of hydrogen to 5,000psi in the first place takes a fair bit of energy, too. Calculation of the actual amount of energy required is left as an exercise for the reader.)