9/16/2023 0 Comments Nuclear fission reactor typesImproved fuels and growth in small reactors could be a big part of a nuclear power rebirth.All nuclear fission power reactors run on fuel containing uranium and other isotopes, but fueling a nuclear reactor is a lot more complicated than driving up to them with a dump truck filled with uranium ore and filling ‘er up. (Rosatom is making small reactors, too.) And a group of Western states has entered a tentative deal with NuScale Power in Oregon for a dozen of its modular reactors. Meanwhile Senator Lisa Murkowski of Alaska is advocating for very small, modular reactors being developed at Idaho National Laboratory. legislators proposed measures to restart licensing for the Yucca Mountain nuclear waste repository in Nevada, touted since 1987 as the country’s leading storage site. This spring, surprisingly, more than a dozen U.S. In the U.S., lack of a permanent, deep geological repository for spent nuclear fuel has long put a brake on expanding the industry. China reportedly intends to connect a demonstration helium-cooled reactor to its grid this year. Manufacturers are also experimenting with “fourth generation” models that use liquid sodium or molten salt instead of water to transfer heat from fission, removing the possibility of dangerous hydrogen production. Westinghouse and other companies have incorporated passive safety features into their updated designs as well. Russia is also deploying other safety measures recent installations at home and abroad by the state-run company Rosatom have newer “passive” safety systems that can squelch overheating even if electrical power at the plant is lost and coolant cannot be actively circulated. These markets could be lucrative for the manufacturers of these new fuels. and is being phased out in Germany and elsewhere, Russia and China are building aggressively. In a bonus, the new fuels could help plants run more efficiently, making nuclear power more cost-competitive-a significant motivation for manufacturers and electric utilities because natural gas, solar and wind energy are less expensive.Īlthough nuclear power has stalled in the U.S. Thorough in-core testing, which has begun, would have to prove successful, and regulators would have to be satisfied. The new configurations could be slipped into existing reactors with little modification, so they could be phased in during the 2020s. In others, zirconium and even the uranium dioxide are replaced with different materials. In some of the variations, the zirconium cladding is coated to minimize reactions. Manufacturers such as Westinghouse Electric Company and Framatome are hastening development of so-called accident-tolerant fuels that are less likely to overheat-and if they do, will produce very little or no hydrogen. (The 1986 Chernobyl accident was caused by faulty reactor design and operation.) and the 2011 explosions and radiation release at Fukushima Daiichi in Japan. That scenario fed two of the world’s worst reactor accidents: the 1979 potential explosion and partial meltdown at Three Mile Island in the U.S. Trouble is, if the zirconium overheats, it can react with water and produce hydrogen, which can explode. Zirconium allows the neutrons generated from fission in the pellets to readily pass among the many rods submerged in water inside a reactor core, supporting a self-sustaining, heat-producing nuclear reaction. That risk could be greatly reduced.Ĭommercial reactors have used the same fuel for decades: small pellets of uranium dioxide stacked inside long cylindrical rods made of a zirconium alloy. Controlling carbon in the atmosphere will require a mix of energy technologies-potentially including nuclear reactors, which emit no carbon but are seen as risky because of a few major accidents.
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