![]() 14 Managing nuclear waste requires very long-term planning. ![]() Ten years after use, the surface of a spent fuel assembly releases 10,000 rem/hr of radiation (in comparison, a dose of 500 rem is lethal to humans if received all at once).In 2011, 27% of spent fuel was held in dry casks, after sufficient cooling in storage pools. Dry casks, large concrete and stainless steel containers, are designed to passively cool radioactive waste and withstand natural disasters or large impacts. spent fuel pools are reaching capacity, necessitating the use of dry cask storage. The process reduces waste and extracts 25-30% more energy than non-reprocessed fuel. Many countries, though not the U.S., reprocess used nuclear fuel.Spent fuel is placed in a storage pool of circulating cooled water to absorb heat and block the high radioactivity of fission products.Spent fuel is 95% non-fissile U-238, 3% fission products, 1% fissile U-235, and 1% plutonium. During reactor operation, fission products and transuranics that absorb neutrons accumulate, requiring a third of the fuel to be replaced every 12-18 months.annually accumulates about 2,000 mt of spent fuel. For PWRs and BWRs most environmental impacts are caused by the extraction and production of fuel elements.Uranium is mostly extracted by open pit mining (16.1%), underground mining (20%) and in-situ leaching (ISL) (57.4%).Nuclear power plants consume 270-670 gallons of water/MWh, depending on operating efficiency and site conditions.The life cycle GHG intensity of nuclear power is estimated to be 34-60 gCO 2e/kWh-far below baseload sources such as coal (1,001 gCO 2e/kWh).Although nuclear electricity generation itself produces no GHG emissions, other fuel cycle activities do release emissions.Each kWh of nuclear electricity requires 0.1-0.3 kWh of life cycle energy inputs.16 Typical reactors hold 18 million pellets. height and diameter) contains the energy equivalent of one ton of coal or 149 gallons of oil. plants currently use “once-through” fuel cycles with no reprocessing. Powering a one-gigawatt nuclear plant for a year can require mining 20,000-400,000 mt of ore, processing it into 27.6 mt of uranium fuel, and disposing of 27.6 mt of highly radioactive spent fuel, of which 90% (by volume) is low-level waste, 7% is intermediate-level waste, and 3% is high-level waste. The nuclear fuel cycle is the entire process of producing, using, and disposing of uranium fuel. nuclear plants have typically been 2 to 3 times higher than original estimates. Estimated LCOE for new nuclear plants built in the near future are about two times higher than estimates for solar, wind, and combined cycle natural gas plants.Estimated LCOE for plants built in the near future are: combined cycle natural gas: 3.99 ¢/kWh advanced nuclear: 8.17 ¢/kWh and biomass: 9.02 ¢/kWh. Levelized cost of energy (LCOE) includes the lifetime costs of building, operating, maintaining, and fueling a power plant.Countries generating the next largest amounts of electricity using nuclear were France, China, and Russia. generated nearly a third of the world’s nuclear electricity. ![]() 3,4 As of May 2022, 55 reactors were under construction, including 2 in the U.S.
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