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LLNL, Ampera partner to develop thorium-based TRISO fuel
Lawrence Livermore National Laboratory has formed a strategic partnership with Ampera to develop the company’s nuclear fuel concept through a project named THUNDER, for Thorium Unimodal Droplet Ejection for Reactors.
The focus of THUNDER is fabricating TRISO made with kernels of thorium rather than the usual uranium. LLNL and Ampera will evaluate and optimize liquid metal–jetting technology to produce highly uniform, spherical kernels of thorium-232 for later processing into TRISO fuel.
Milorad Dusic, Mark Dutton, Horst Glaeser, Joachim Herb, Javier Hortal, Rafael Mendizábal, Fernando Pelayo
Nuclear Technology | Volume 188 | Number 1 | October 2014 | Pages 63-77
Technical Paper | Reactor Safety | doi.org/10.13182/NT13-16
Articles are hosted by Taylor and Francis Online.
In 2009 the International Atomic Energy Agency (IAEA) published “Deterministic Safety Analysis for Nuclear Power Plants Specific Safety Guide,” Specific Safety Guide No. SSG-2 (hereinafter referred to as SSG-2). SSG-2 addresses four options for the application of deterministic safety analyses. Option 1, which has been used since the early days of civil nuclear power and is still used today, uses conservative codes/models and conservative initial and boundary (I&B) conditions. Option 2, which is frequently used worldwide, uses realistic codes/models but with conservative I&B conditions. Option 3 uses realistic codes/models and realistic I&B conditions and therefore needs also to consider the associated uncertainties. Today, option 3 is known as the Best Estimate Plus Uncertainty option. Option 4 is not developed in SSG-2 and only indicates that option 4 is an attempt to combine insights from probabilistic safety analyses with a deterministic approach, which results in a risk-informed safety analysis. In options 1, 2, and 3, the availability of safety systems is based on conservative assumptions, whereas in option 4, the availability of safety systems is derived by probabilistic means. This paper explains in more detail the approach proposed for option 4 and provides illustrative examples for its application, recognizing the fact that option 4 is still a research option and will remain so for some time.