SAN DIEGO--Fifty years after the laser was born, its descendants include devices that could soon peer through three feet of steel and detect the smallest cancers. But its most important offspring could be a technology that puts a clean energy future in reach within decades, experts said at the AAAS Annual Meeting.
Using powerful lasers to slam hydrogen atoms together at speeds of a million miles per hour, researchers at the National Ignition Facility outside of San Francisco hope to create a source of fusion energy, said project director Edward Moses, "similar to building a very small star on Earth."
If they succeed, the fusion technology could solve "one of the great challenges of humanity," said Moses, by providing "unlimited, carbon-free" energy to power the planet within the next three to four decades.
A metallic case called a hohlraum holds the hydrogen fuel capsule for National Ignition Facility experiments.[Credit: Lawrence Livermore National Laboratory]
A metallic case called a hohlraum holds the hydrogen fuel capsule for National Ignition Facility experiments.
[Credit: Lawrence Livermore National Laboratory]
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The research at the National Ignition Facility is in its early stages--the scientists still need to ignite a fusion reaction. But its early experiments have been successful, and Moses said researchers have already begun talking to power utilities and Silicon Valley manufacturers about ways to scale up the technology for public use if progress continues.
Fusion power comes from the immense energy released when two lightweight atoms collide and join. It's a process that happens in the sun's core, where intense gravitational pressures easily meld atoms, but the same kind of reaction is difficult to produce on Earth. The history of fusion power is littered with false starts, dead ends, and even some cases of outright scientific fraud.
Moses' fusion project is "built on lasers that were thought about 50 years ago and are operational now," he said. The powerful lasers fire on a pencil eraser-sized capsule containing hydrogen, but future power plants would probably be fueled by the hydrogen molecules in water. "A swimming pool of water has enough energy," said Moses, "to power California for a year."
Well-equipped with their own laser pointers and flashing lapel pins, the AAAS panel included Thomas Baer, executive director of the Stanford Photonics Research Center; physicist Margaret Murnane of the Joint Institute for Laboratory Astrophysics; Christopher Barty, a program director at Lawrence Livermore National Laboratory; and Wim Leemans of the Lawrence Berkeley National Laboratory.
The speakers said advances in the power, focus, and speed of laser technology could prove useful in medical imaging, the detection of clandestine weapons, and techniques to watch chemical and biological reactions unfold in real time.