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Division Spotlight
Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
Meeting Spotlight
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
L. B. Freeman, B. R. Beaudoin, R. A. Frederickson, G. L. Hartfield, H. C. Hecker, S. Milani, W. K. Sarber, W. C. Schick
Nuclear Science and Engineering | Volume 102 | Number 4 | August 1989 | Pages 341-364
Technical Paper | doi.org/10.13182/NSE89-A23647
Articles are hosted by Taylor and Francis Online.
The light water breeder reactor (LWBR) operated at the Shippingport Atomic Power Station from 1977 to 1982, serving the electric power grid for the Greater Pittsburgh area. The LWBR was a pressurized water reactor (PWR) with several unique features: It was designed and proved to be a breeder with an end-of-life fissile fuel content ∼1.3% greater than beginning of life; the reactor used the 233U-Th fuel system; and it had a large Doppler coefficient, low reactivity worth of transient xenon, and a significant reactivity effect from transient 233Pa. There were no control rods or soluble poison, and reactivity was controlled by movable fuel. Core operations went extremely well. The design lifetime of 18 000 effective full-power hours was exceeded by 60% by utilizing a gradual reduction in power level. The overall capacity factor was 65%. Physics experiments showed good agreement with predictions of movable fuel reactivity worth, most temperature coefficients, breeding, power distribution, and xenon stability. Unexpected results occurred in measurements of flow coefficient of reactivity, zero power temperature coefficients early in life, and bred fissile fuel distribution. The LWBR technology has demonstrated that water-cooled breeder reactors can operate in existing water power plants much like conventional PWRs.