VALVE MAGAZINE Winter 2025

NUCLEAR POWER

energy as 3 million pounds of coal — making it an incredibly efficient fuel source despite potential safety risks. Radiation is measured in “half-life” or the length of time it takes a material to lose half of its radioactivity. U-238, the most common form of uranium in nuclear plants, has a half-life of 4.5 billion years, and uranium U-235 of about 700 million years. With that in mind, it’s critical that there are safe and effective handling, disposal and storage mechanisms for spent fuel to maintain nuclear as a viable option. Use and recycling of nuclear fuel According to the World Nuclear Association, recycling today is largely based on converting U-238 to plutonium. This plutonium can then be used again as fresh fuel for fission power generation, as is currently the case in Japan, France, Russia and China, but other countries are not yet reprocessing the materials. By reprocessing used material to recover uranium and plutonium, operators not only avoid wasting valuable materials but also eliminate some of the

These spacer grids were designed through a Westinghouse/ Carnegie Mellon collaboration then 3D printed as one piece replacing a very complicated assembly requiring joining many pieces with one piece. Source: Additive Manufacturing

waste stream. To date, World Nuclear estimates about 30% of spent fuel from nuclear power plants has been reprocessed. In the U.S., the Nuclear Waste Policy Act of 1982, as amended, declares that the federal government is responsible for providing a place to permanently store high-level radioactive waste, while those who generate the waste are responsible for all costs of permanent disposal. This Act has been amended over time, and the U.S. government has designated Yucca Mountain, Nevada, as the permanent site for nuclear waste for the U.S., although the facility is still on hold so there is currently no waste at the site, or a completed facility for storage. Other sites may be considered in the future but must have crystalline rock formations and partic ular geological qualities to deem them suitable for permanent and safe storage. Nuclear fuel is solid and is used as small ceramic pellets of enriched uranium oxide, encased in metal cladding to form fuel rods. The rods are bundled together into assem blies that are placed into the

Source: World Nuclear Association

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WINTER 2025

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