nuclear fusion breakthrough

The U.S. is on the cusp of announcing a scientific breakthrough that has eluded researchers worldwide for decades — one that could, decades from now, turn nuclear fusion into a practical source of clean, inexpensive energy that doesn’t create long-lived radioactive waste or worsen global warming.

The findings, which Energy Secretary Jennifer Granholm is expected to announce Tuesday, still leave many obstacles to be resolved in turning the nuclear process that powers the sun into a source of Earth-bound energy. But scientists are embracing the historic milestone nonetheless, cheering that researchers have finally created a fusion reaction that produces more energy than it takes in.

Turning that discovery into a source of power for everyday life would probably take decades and cost several hundred billion dollars, said Dale Meade, a retired fusion expert who worked at the Princeton Plasma Physics Laboratory in New Jersey, one of the Energy Department’s national labs. But such a massive effort would be worthwhile, he said.

“Perhaps the greatest challenge of all is whether the U.S. has the foresight and will to move forward,” Meade said.

The Financial Times first reported the research breakthrough Sunday. A person familiar with the findings confirmed to POLITICO that DOE will announce that its Lawrence Livermore National Laboratory had used lasers to produce a fusion reaction that generated 1.2 times more energy than was needed to create it.

If reports of the experiment’s results prove accurate, “it’s one of the biggest results of science in the past 20-30 years,” said Gianluca Sarri, a professor at Queen’s University Belfast who researches laser and plasma physics. But even then, hope of a fusion-generation power plant is still more than a decade away, he said.

Fusion, which uses extreme heat to combine two atoms and produce massive amounts of energy as a byproduct, is the engine that powers the sun and the stars, as well as advanced thermonuclear weapons. Unlike existing nuclear plants, which harness heat from a chain reaction of splitting atoms in a process called fission, fusion reactors don’t generate a panoply of radioactive waste or pose a risk of meltdowns. Since the 1950s, supporters of the technology have claimed that fusion could someday produce energy that’s cheap and essentially limitless.

But showing that a fusion reactor is even a practical goal has been difficult. A little over a year ago, though, Lawrence Livermore’s National Ignition Facility announced that it was finally nearing the step of creating a fusion reaction that produces a net-positive amount of energy.

That still leaves plenty of enormous technological and regulatory challenges, such as finding ways to convert the energy released in the fusion process into electricity.

Former Rep. Rush Holt (D-N.J.), a physicist who was assistant director of the Princeton Plasma Physics Lab, said in an interview that he found the news of the breakthrough "technically interesting, but I'm skeptical about its practicality."