CNN
—
U.S. Department of Energy officials on Tuesday announced a historic achievement for nuclear fusion: For the first time, U.S. scientists have generated more energy from fusion than the laser energy they used to power the experiment.
The so-called “net energy gain” is a major milestone in the decades-long attempt to harvest clean, limitless energy from nuclear fusion — the reaction that occurs when two or more atoms fuse together.
The experiment delivered 2.05 megajoules of energy to the target and produced a fusion power output of 3.15 megajoules — 50 percent more energy than the input. This is the first time the experiment resulted in a meaningful increase in energy.
Live Update: U.S. Officials Announce Nuclear Fusion Breakthrough
“This monumental scientific breakthrough is a milestone for a clean energy future,” said the Democratic U.S. senator. Alex Padilla of California, in a statement.
A breakthrough was made on Dec. 5 by a team of scientists at the National Ignition Facility at Lawrence Livermore National Laboratory in California, a facility the size of a stadium and equipped with 192 lasers.
Energy Secretary Jennifer Granholm called the breakthrough a “milestone” on Tuesday.
“Ignition allows us to replicate for the first time certain conditions found only in stars and the sun,” Granholm said. “This milestone moves us closer to the possibility of zero-carbon, abundant fusion energy to power our society.” an important step forward.”
Granholm said the work being done by Livermore and scientists at other national labs will help the United States quickly transition to clean energy and maintain a nuclear deterrent without nuclear testing.
“This is what American leadership looks like, and we’re just getting started,” Granholm said. “If we can advance fusion energy, we could use it to produce clean electricity, transportation fuels, electricity, heavy industry and more.”
Arati Prabhakar, director of the White House Office of Science and Technology Policy, talks about how, as a young early-career scientist, she spent three months at Lawrence Livermore working on its nuclear fusion project.
Prabhakar looks back at the generations of scientists who made nuclear fusion what it is today. “It’s not just one generation, it’s generations that are pursuing this goal,” she said. “It’s been a century since we discovered that what’s going on in our sun and all the other stars is nuclear fusion. In that century we’ve made so many different types of advances that eventually came together that we can make replicate this fusion activity.”
We’re still a long way from getting fusion power into the grid, experts warn. Tony Roulstone, a fusion expert at the University of Cambridge’s engineering department, told CNN that the U.S. project, while groundbreaking, only produces enough energy to boil about 2.5 gallons of water.
That might not seem like much, but this experiment is still very important, as the scientists proved that they could create more energy than they started with. While there are many steps ahead before it becomes commercially viable, this is the main hurdle in getting past fusion, experts say.
On Tuesday, Lawrence Livermore National Laboratory director Kim Budil called her lab’s breakthrough a “foundational building block” for the eventual realization of fusion power generation. She estimated that it would be “decades” before it could be used commercially.
“I think it’s coming to the fore, and maybe with a joint effort and investment, decades of research into the underlying technology could allow us to build a power plant,” Budir told reporters. “With real investment and real focus , this time scale can be closer.”
Past fusion experiments, including those in the UK, produced more power, but not by such a large energy gain. Earlier this year, for example, British scientists generated a record 59 megajoules of energy—roughly 20 times more than the US project. Even so, the UK project has shown an energy gain of less than 1 MJ.
Anne White, chair of MIT’s Department of Nuclear Science and Engineering, told CNN that neither the U.S. nor the U.K. project “has the hardware and the steps to convert fusion neutrons into electricity.”
Magnet fusion projects in Europe and laser systems in the United States could work together to move fusion forward, Budil said. The federal government also welcomes private investment in fusion, Granholm added.
Budil stresses that there are still many steps to be taken in the coming decades before fusion power can light our lights and heat our water.
“I don’t want you to think that we’re going to connect the NIF to the grid; that’s not how it works,” she said.
But Roulstone points out that ambitious, large-scale nuclear power projects have to start somewhere: In 1942, scientists in Chicago ran the first fission nuclear reactor for just five minutes on its first run; Nuclear power plants come online in Pennsylvania.