US Scientists Have A Wild Plan To Convert Nuclear Waste Into Fuel For Nuclear Reactors
For decades, the world has grappled with how to safely and permanently dispose of vast amounts of highly radioactive waste from fission reactors. Now, a bold solution has emerged that could turn this liability into a valuable asset. Researchers are advancing a concept that could use spent nuclear fuel to produce tritium, a rare and critical fuel source for the next generation of clean energy, i.e. nuclear fusion.
The research, spearheaded by physicist Terence Tarnowsky and his team at Los Alamos National Laboratory, could address two large energy problems at once. Today's nuclear power plants generate energy by nuclear fission, the process of splitting heavy atoms like uranium. This creates long-lived radioactive waste that requires expensive, long-term storage. Meanwhile, the future of clean energy is widely believed to be nuclear fusion, the same process which powers the sun, by fusing light atoms. While fusion promises a near-limitless supply of energy with minimal waste, its widespread adoption has a major hurdle: it requires a reliable supply of tritium.
Tritium is a radioactive isotope of hydrogen, alongside its stable sister, deuterium. While deuterium is abundant in seawater, tritium is incredibly scarce and costly. According to Tarnowsky, a pound of commercial tritium can be worth around $15 million, and the United States currently has no domestic production capability.
Tarnowsky and his colleagues' proposed solution involves an accelerator-driven system (ADS). This theoretical reactor design would use a particle accelerator to bombard spent nuclear fuel with particles. This process would induce controlled fission reactions, releasing neutrons that would then be harvested in a molten lithium salt medium to create tritium.
Simulations of this process have shown promising results. A 1 gigawatt ADS could potentially produce approximately 2 kilograms (4.4 pounds) of tritium annually. This is a remarkable output, on par with the total yearly production from all current Canadian reactors, which are currently a major commercial source. The most significant finding is that this new system would be incredibly efficient, producing more than ten times as much tritium as a fusion reactor operating at the same thermal power. This efficiency could drastically reduce the cost barrier for future fusion plants.
No doubt, the proposed system also offers a solution to the nuclear waste problem. By consuming long-lived transuranic elements in spent fuel, the process would effectively nullify the most hazardous components of the waste, reducing the required storage period from hundreds of thousands of years to just a few centuries.
This groundbreaking new concept is still in the simulation and modeling stage, however. The next steps for the researches involve refining their models to improve efficiency and performing a detailed cost-benefit analysis. Ultimately, the goal is to provide policymakers with a viable, cost-effective, and safe roadmap to production scale implementation of the technology.
