Breakthroughs over the last three months in both inertial and magnetic containment fusion challenge the U.S. government to get serious about commercial fusion power. Today, the House Committee on Science, Space, and Technology’s Subcommittee on Energy held a hearing entitled, “Fostering a New Era of Fusion Energy Research and Technology Development.” Chairman Jamaal Bowman (D-NY), in his own way, put wind and solar as a byproduct of fusion: “It is a simple fact that this fundamental phenomenon [of the Sun’s fusion process] is essential to existence of vital renewable energy sources like solar and wind energy, and indeed to life on Earth.” Then he described the two breakthroughs. On Aug. 8, “the National Ignition Facility (NIF) at DOE’s Lawrence Livermore National Laboratory produced the first so-called ‘burning plasma’ in a man-made experiment. A burning plasma is a condition in which the fusion process itself provides the primary heat source to sustain the fuel’s high temperatures that keep the fusion process going.” Then, on Sept. 5, Commonwealth Fusion Systems (CFS) and its partners at MIT achieved a successful test of a high-temperature superconducting magnet up to a field strength of 20 tesla, the most powerful magnetic field of its kind ever created on Earth. Such a magnet could enable fusion systems that are significantly smaller, lower cost, and faster to build than what was previously thought possible.”
In 2018, the Department of Energy’s Research and Innovation Act called for producing a long-range strategic plan for commercial fusion, including resolving how to “prioritize research activities and facility construction plans under a range of plausible budget scenarios.” That team has delivered its long-range plan, entitled “Powering the Future: Fusion and Plasmas,” which was central to today’s testimony. At the end of the hearing, Bowman said this was an “amazing hearing … about a topic that I think will take our economy and humanity into the future.” [https://science.osti.gov/-/media/fes/fesac/pdf/2020/202012/DRAFT_Fusion_and_Plasmas_Report_120420.pdf?la=en&hash=0BC10F27FAFFCDF79867E08ECDF762C16434F8D5]
Prof. Troy Carter, the director of the Plasma Science and Technology Institute, is on the DOE’s Office of Science Fusion Energy Sciences Advisory Committee (FESAC). He chaired the team that produced the 10-year strategy for fusion and plasma technologies. He testified that the super-heated, ionized gas “has myriad applications beyond fusion energy,” but he focused in upon the task of achieving commercial fusion: “The main message of my remarks is that now is the time to move aggressively toward the development and deployment of fusion energy,” because of “important scientific and technological progress” including “advances in our understanding of fusion plasmas and achievement of new performance records.” NIF’s August breakthrough achieved “extremely high fusion gain ... enabled by recently acquired scientific understanding” and would be described by Prof. Tammy Ma (below). And the CFS “high-temperature superconducting (HTS) magnet” would be addressed by their CEO, Bob Mumgaard.
Dr. Tammy Ma, whose title is Program Element Leader for High-Intensity Laser High Energy Density Science, National Ignition Facility & Photon Science, described the inertial confinement breakthrough at Lawrence Livermore National Laboratory. Ma has been involved in the inertial confinement fusion (ICF) experiments at NIF since 2009. There were breakthroughs in both the “capsule gain” and the “burning plasmas” which “have placed us on the threshold of fusion ignition where energy gain from nuclear fusion in the capsule exceeds the laser energy delivered.” The 2020 FESAC Long Range Strategic Plan calls for inertial fusion to be brought up closer to magnetic confinement research.
Specifically, a yield of 1.35 megajoules was achieved at NIF, using 1.9 megajoules of laser input—or about 70% of so-called breakeven. This was eight times better than a few months before, and 100 times better than a year ago. So, the work there has gone from less than 1% of what’s needed, to less than 9%, now to 70%. NIF’s massive laser results from amplifications through thousands of optical elements. It is then focused onto a miniature, highly engineered target the size of a BB, with fusion fuel inside the capsule. Their initial analysis indicates that more than 10 quadrillion watts of fusion power was achieved for 100 trillionths of a second from a 50-micron-size burning plasma. And the energy released over energy absorbed by the capsule was greater than five.
