HOW TO SAVE THE PLANET

Understanding Nuclear Fusion at the INL

BY HARPER CRABTREE

Last December, the Lawrence Livermore National Laboratory in California passed a scientific milestone by achieving a net positive through nuclear fusion, which is a different process than nuclear fission. I know what you’re thinking. Even simplified, these scientific terms sound nebulous and confusing because they’re invisible in our daily lives. Seeking answers for the normal person, I traveled to the Idaho National Laboratory (INL) in Idaho Falls to understand nuclear fusion and how it might impact our future and the environment.

The recent breakthrough in fusion ignition is being compared to the Wright Brothers’ first flight at Kitty Hawk. Why? Because it heralds the first step in our very necessary environmental need for clean, limitless energy. In the words of Joe Campbell, a communications liaison for the Idaho National Laboratory, “Fission reactors were like the first quantum leap over fossil fuels. And then fusion is the next quantum leap past that.”

Photo courtesy of the Idaho National Laboratory

Scientists have been chasing the concept of fusion since the 1930s. The event at Lawrence Livermore National Laboratory means that they finally accomplished a demonstration of producing more energy from a fusion reaction than they put into it.

What is the process of fusion exactly? How does it differ from fission, which was discovered in 1938 and provided the basis of the atomic bomb and nuclear reactors at the heart of today’s nuclear power plants? More relevant, perhaps, is why we should pay attention to scientific developments when TikTok is far more accessible and entertaining.

ATR canal operators, experiment engineers and radiological control teams install a Navy experiment into the ATR Gamma Tube for irradiation. The Gamma Tube uses irradiated ATR fuel elements as a radiation source for experiments needing high gamma dose rates.

Photo courtesy of the Idaho National Laboratory

Fusion happens when atoms slam together to form new, heavier atoms, due to incredible temperatures and immense amounts of pressure. Fusion reactions are most commonly found in the core of stars, where temperatures average around 20 million degrees fahrenheit.

Alternatively, nuclear fission occurs when a neutron slams into a larger atom, forcing it to split into two smaller atoms. When each atom splits, energy is released. Fission reactors then use this reaction to heat up large amounts of water, and spin turbines with the resulting water vapor.

STAR lab scientists perform innovative experiments to understand Tritium and its permeability.

Photo courtesy of the Idaho National Laboratory

Nuclear fusion reactions can release massive amounts of energy, and don’t need to spin turbines. “Almost 100% of the universe’s energy comes from nuclear fusion,” said Masashi Shimada, the principal investigator at the INL’s Safety and Tritium Applied Research (STAR) lab. Think about it. Harnessing fusion means that we humans just created our own first spark of the same endless energy that powers the sun. And unlike fission, fusion does not create radioactive byproducts.

How safe is fusion? “Every energy source has its trade offs,” said Chase Taylor, a senior staff scientist at the INL’s STAR facility. “The trade-off for fusion is that the vessel holding the fuel becomes radioactive…that’s not an environmental concern, but it means that everything must be handled with care. This is due to a property of tritium, a radioactive isotope of hydrogen, the main fuel for fusion. Tritium dissolves in all metals, just kind of like dissolving sugar in your Kool Aid,” Taylor said.

Photo courtesy of the Idaho National Laboratory

Right now, Shimada, Taylor, and Fuerst are among a group of INL’s STAR lab scientists performing cutting edge experiments to better understand tritium and its permeability with other materials. This research is so innovative that they are required to invent their own tools. “Some metals dissolve tritium really well, but other metals don’t dissolve it at all. So one material can be used as a barrier for tritium, while other materials can be used to allow the tritium to pass through,” Taylor said.

Photo courtesy of the Idaho National Laboratory

“Fusion has the highest energy density of any sort of energy source with zero carbon emission,” Fuerst explained. In other words, no global warming, no Chernobyl, or vast amounts of radioactive waste with an endless shelf life. The byproduct of nuclear fusion is helium, and the world is actually in a helium shortage right now. So the next time you hear about a fusion breakthrough, remember that one small step in clean energy development is taking us closer to saving the planet—and our own lives— for thousands of years into the future.