Scientists Close to Producing Fusion Energy

ALBUQUERQUE, N.M. (August 6, 1997 00:15 a.m. EDT) -- The world's most powerful X-ray generator at Sandia National Laboratories is fast approaching the torrid region in which fusion energy might be produced.

The generator has achieved a temperature of 1.5 million degrees Celsius, strengthening the labs' hand in asking the U.S. Department of Energy to pay for a bigger successor to the Z accelerator -- the $300 million X-1 accelerator.

Scientists say fusion would be a cleaner source of electricity than coal, oil or the nuclear-fission energy that powers nuclear reactors.

With the new X-1, Sandia scientists believe they could demonstrate fusion technology for energy production and for nuclear-weapons simulations.

"If fusion can be made to work in a very cost-effective way, there will not be future wars over oil in the Persian Gulf or anywhere else and the injury to the environment caused by civilization will be reduced," said Don Cook, director of Sandia's Pulsed Power Sciences Center.

Pulse power is the foundation Z technology in which Sandia is a world leader. It allows the accelerator to bank energy and then release it instantly at a target. The trigger creates a spectacular rush of lightning across a pool of water used to transmit the energy.

"We have told DOE that we would be knocking on the door," Jeff Quintenz, Sandia's program manager for Inertial Confinement Fusion, said of the latest test results from the Z accelerator. Inertial Confinement Fusion is a military program.

A formal proposal may be made this year if the next round of experiments equals or breaks 1.7 million degrees, he said.

While the lab cannot predict when the mark will be reached, Quintenz said, Z has dramatically climbed the fusion thermometer, notching records in months that were expected to take years.

At that rate, Quintenz said, "by Christmas we'll be melting down the universe."

Fusion energy, the nuclear reaction that powers the sun, stars and nuclear bombs, requires intense temperatures in the range of 2 million to 3 million degrees.

The latest Z results are being broadly praised across the country and compared to Sandia's competitor, the $1.2 billion National Ignition Facility.

The NIF is a fusion laser under construction at Livermore National Laboratory in California and is designed to ignite a hydrogen fuel pellet to produce fusion energy.

The NIF laser project, which is DOE's top simulator for nuclear-weapons blasts, is being questioned by nuclear-weapons scientists.

Some scientists have said the country needs the NIF, X-1 and other simulators to maintain reliable warheads without nuclear testing. But others have questioned whether NIF will work as promised and whether it has any application to weapons stewardship.

Sandia's X-ray accelerator, some scientists say, may be a cheaper alternative and a better bet for military uses and fusion-energy reactors.

"The implications are beginning to dawn on people," Cornell University physicist David Hammer said in an article last month in the journal "Science."

Hammer described Sandia lab's experiments as "spectacular." A companion piece was headlined "A Harsh Light Falls on NIF."

Carl Ekdahl, program manager for Sandia's high-energy density physics program, is an enthusiastic Z-accelerator supporter. His scientists are conducting weapons-related experiments at Sandia.

"My program is and will continue to be one of the largest users of Z for weapons physics," he said. "Sandia researchers are way ahead of schedule. They fill a niche that no other facility in the world fulfills."

DOE's assistant secretary for defense programs, Vic Reis, sent Sandia his "heartiest congratulations." Reis is an ardent supporter of the National Ignition Facility.

"With this world record result, the Z machine proves once again that the people at Sandia are up to the challenge of science-based (nuclear weapons) stockpile stewardship," he said.

Z technology is the conversion of Sandia's ion-beam blaster, the Particle Beam Fusion Accelerator II, which did not reach scientific milestones.

Sandia managers have decided for now to abandon ion-beam research beginning with the 1999 budget to concentrate on the Z approach, Quintenz said.

By LAWRENCE SPOHN, The Albuquerque Tribune