Nuclear fusion holds the promise of nearly limitless, zero-emission energy. But its success hinges on one rare and costly ingredient – tritium, a volatile isotope of hydrogen essential for deuterium-tritium (D–T) fusion but scarcely available.
Thanks to a Los Alamos National Laboratory effort to convert decades of stored nuclear waste into a tritium production factory with a novel molten-salt, accelerator-driven system, that could soon change.
The tritium challenge
Tritium doesn’t exist abundantly in nature, and its supply is dwindling. Experts estimate that a 2-gigawatt D–T fusion plant would require about 112 kilograms of tritium annually.
Yet, researchers believe that just 25 kg currently exist worldwide, most from nuclear reactor byproducts, and are unavailable commercially.
Fusion developers rely on heavy-water reactors like Canada’s CANDU reactors to supply limited tritium.
Even then, projections for a future DEMO-class reactor – meant to follow the experimental ITER – suggest available tritium from global sources may range from zero to just 28 kilograms by 2055.
This scarcity raises a critical question: How can fusion go commercial without a renewed tritium supply?
Los Alamos’ molten-salt accelerator system
Enter Terence Tarnowsky’s team at Los Alamos, who are exploring a system that uses particle accelerators and molten lithium salt to produce commercial tritium from nuclear waste.
The process leverages neutron generation in the salt to convert dissolved lithium into tritium – with no nuclear chain reaction involved, providing a potential safety edge.
Early simulations indicate promising potential: a 1-gigawatt version could yield about 2 kilograms of tritium annually – comparable to Canada’s current output – while being over ten times more efficient per unit power than fusion-based breeding.
Tarnowsky is advancing design models, including cost estimates, and integrating molten lithium salt as a coolant. This would enhance security and traceability in handling radioactive materials.
Global competition in tritium production
The U.S. isn’t the only player tackling tritium shortfalls. In Europe, ITER aims to test tritium breeder blankets – layers of lithium designed to regenerate fuel from fusion-generated neutrons.
These experimental systems are still vital for achieving tritium self-sufficiency in reactors.
Meanwhile, the UK and Canada have launched a joint research initiative to enhance tritium production and processing infrastructure – a geopolitical necessity with fusion commercialization on the horizon.
Commercial innovation is emerging, too. Astral Systems, a fusion startup in the UK, recently became the first private firm to breed tritium from a lithium blanket in their experimental reactor – a major step in solving fusion’s fuel supply challenge.
Fusion’s momentum in recent years has been notable. The U.S. Fusion Industry Association reports that nearly $9.7 billion was raised by 53 fusion companies worldwide – up from $1.9 billion a few years ago.
Major players like Microsoft and Google are already committing to buy fusion-generated power, underscoring growing confidence in the technology.
Commonwealth Fusion Systems aims to deliver net energy from its SPARC tokamak by 2027 and bring the first commercial-scale power plant online in Virginia in the early 2030s.
But tritium remains the linchpin. Without a stable, scalable supply, even the most advanced fusion concepts risk running out of fuel before power generation begins.
Why Los Alamos’ approach matters
The accelerator-driven, molten-salt concept offers flexibility, safety, cost control, and connects with existing waste streams. It promises a scalable path to unlocking fusion’s potential – converting a liability (nuclear waste) into a strategic advantage.
Whether its method will outpace other tritium-generating approaches remains to be seen.
But in an industry racing from lab breakthroughs to grid-scale energy, securing the fuel may be just as critical as containing the plasma.
One fusion analyst noted, “Creating tritium at scale may make or break our ability to achieve clean fusion power; Los Alamos may have found a game-changing path.”
