spent fuel

Spent fuel refers to the used radioactive material removed from a nuclear reactor after it has generated energy. When nuclear fuel, typically uranium, is used in a reactor, it undergoes fission, releasing energy to produce electricity. Over time, the fuel becomes less efficient and accumulates radioactive byproducts, making it hazardous. This used fuel is carefully stored, often in cooling pools or dry casks, to shield people and the environment from radioactivity. While it no longer efficiently produces energy, it remains highly radioactive and needs secure, long-term management due to its potential health and environmental risks.