Discover magazine Runs Article on Focus Fusion

Posted by Admin on May 06, 2008 at 04:14 PM
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Click here to see the full article. And here is the text of the section on Fusion:

2) Fusion On Tap
Plasma physicist Eric Lerner has a dream: a form of nuclear energy so clean it generates no radioactive waste, so safe it can be located in the heart of a city, and so inexpensive it provides virtually unlimited power for the dirt-cheap price of $60 per kilowatt�far below the $1,000-per-kilowatt cost of electricity from natural gas.

It may sound too good to be true, but the technology, called focus fusion, is based on real physics experiments. Focus fusion is initiated when a pulse of electricity is discharged through a hydrogen-boron gas across two nesting cylindrical electrodes, transforming the gas into a thin sheath of hot, electrically conducting plasma. This sheath travels to the end of the inner electrode, where the magnetic fields produced by the currents pinch and twist the plasma into a tiny, dense ball. As the magnetic fields start to decay, they cause a beam of electrons to flow in one direction and a beam of positive ions (atoms that have lost electrons) to flow in the opposite direction. The electron beam heats the plasma ball, igniting fusion reactions between the hydrogen and boron; these reactions pump more heat and charged particles into the plasma. The energy in the ion beam can be directly converted to electricity�no need for conventional turbines and generators. Part of this electricity powers the next pulse, and the rest is net output.

A focus fusion reactor could be built for just $300,000, says Lerner, president of Lawrenceville Plasma Physics in New Jersey. But huge technical hurdles remain. These include increasing the density of the plasma so the fusion reaction will be more intense. (Conventional fusion experiments do not come close to the temperatures and densities needed for efficient hydrogen-boron fusion.) Still, the payoff could be huge: While mainstream fusion research programs are still decades from fruition, Lerner claims he requires just $750,000 in funding and two years of work to prove his process generates more energy than it consumes. �The next experiment is aimed at achieving higher density, higher magnetic field, and higher efficiency,� he says. �We believe it will succeed.�