Sonofusion: a working nuclear-fusion reactor that uses bubbles to produce power at a fraction of today’s energy costs and creates almost no pollution.By Cosmo Garvin (Photo By Larry Dalton)
Just who does Ross Tessien think he is? Even Ross Tessien wonders.
"To think some goofy mechanical engineer from Chico State is saying, 'I know how to drive nuclear fusion.' It's ... " he trails off, as if he isn't sure what to make of himself.
His company, Impulse Devices Inc. (IDI), is navigating a strange and obscure corner of science called "sonofusion," or sometimes "bubble fusion." Tessien believes it is possible to use acoustic waves--sound--to squeeze together hydrogen atoms and force them to fuse with each other, releasing tremendous amounts of energy in the process.
Sonofusion, in theory at least, sidesteps some of the problems that have dogged other approaches to fusion. It takes advantage of an intriguing but little understood form of mechanical energy: the power of collapsing bubbles. If they are right, the discovery will turn the field of nuclear-fusion research upside down. It also could do the same to the global energy industry.
The fuel that would drive such a fusion reactor is deuterium. One gallon of water potentially contains enough deuterium for the equivalent energy of 300 gallons of gasoline.
In sonofusion, a nuclear reactor is much smaller and simpler than a conventional nuclear-power plant: a clear glass flask of a liquid called deuterated acetone chilled to nearly zero degrees.
Around the flask, a transducer that gives off sound waves sets up a standing wave in the jar making the molecules of acetone vibrate tens of thousands of times a second.
Tessien turns up the transducer to 60 kilohertz, well above the range of human hearing. Then, after a few moments, engineer Satterwhite introduces “the source.”
The source is a metal alug of americium and beryllium isotopes on the end of a 4-foot pole. These radioactive elements send millions of neutrons in every direction.
As soon as Satterwhite pokes the source near the glass cell, the liquid inside starts to sizzle and ping. The neutrons flying off of the source are tearing very small, almost microscopic, holes in the liquid. You can see bubbles flickering in the center of the liquid, where the sound waves are focused.
The temperatures inside these bubbles as they collapse can get to at least 20,000 degrees Celsius -four times hotter than the surface of the sun. Now parts of the liquid are a plasma of nuclei floating freely in an incredibly hot atomic soup. At bubble temperatures of 10 million degrees, deuterium atoms should begin to fuse with each other, just as they do on the inside of a star.