ENERGY SECURITYFueling the Future of Fusion Energy
Long considered the ultimate source of clean energy, nuclear fusion promises abundant electrical power without greenhouse gas emissions or long-lasting radioactive waste. The process has fueled the core of the sun for more than four billion years – with billons more to go. Nore scientists are joining the global pursuit of harnessing that reaction.
Long considered the ultimate source of clean energy, nuclear fusion promises abundant electrical power without greenhouse gas emissions or long-lasting radioactive waste. The process has fueled the core of the sun for more than four billion years – with billons more to go. Now, the U.S. Department of Energy’s Thomas Jefferson National Accelerator Facilityis joining the global pursuit of harnessing that reaction.
Twice in the past year, scientists at DOE’s Lawrence Livermore National Laboratory in California have announced a net energy gain created by combining two or more atomic nuclei. These breakthroughs were decades in the making, and the applied technology has a long way to go be near a commercially viable scale.
That’s why Jefferson Lab and a team of science partners from across the U.S. are working to improve the hardware – and the nuclear fuel. The project has just been awarded funding by DOE’s Fusion Energy Sciences Office.
A Rare Collaboration
Jefferson Lab is on the ground level of a multi-year, combined research venture to measure spin-polarized fusion (SPF). If achieved, SPF will lower the requirements for the ignition of a burning plasma in a fusion reactor.
Atomic nuclei have a behavior akin to a spinning top. Low temperatures and high magnetic fields can be used to “polarize” all the nuclei in a fuel pellet by forcing them to all spin in the same direction. When polarized, particles spin parallel to the surrounding magnetic field. Aligned this way in a fusion reactor, deuterium (heavy hydrogen) and helium have a 50% greater chance of fusing. In a large-scale power reactor this should produce 75% more power production, according to recent fusion simulations.
What scientists don’t know, however, is just how long that spin alignment can last. The fuel can be polarized near absolute zero, but the key question is how long that alignment will survive in the hundred-million-degree plasma of a fusion reactor. Only tens of seconds are needed to garner the power boost, and theory predicts the spin alignment should outlast that. But a plasma is the most unstable form of matter, and an experimental test is essential. That is the goal of Jefferson Lab’s research partnership.
Staff Scientist Xiangdong Wei will lead Jefferson Lab’s segment of the effort, which includes researchers from the University of Virginia in Charlottesville; Oak Ridge National Laboratory in Tennessee; University of California, Irvine; and General Atomics’ DIII-D National Fusion Facility in San Diego.
