Oklo’s nuclear reactor design uses highly enriched low-enriched uranium (LEU), a fuel with a much longer lifespan than the LEU currently used in conventional light-water reactors. It can operate for a decade or more without requiring refueling. Today’s nuclear power plants require refueling every 18 to 24 months. At that rate, a light-water reactor would require refueling five times, while the Oklo plant would only require one.