Development of Novel-Fuels with Enhanced Safety Characteristics for Use in Nuclear Power Generation

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Many emerging economies are considering construction of hundreds of new nuclear plants to supply electricity for increasingly electrified economies (including power for electric vehicles) and to offset climate changing emissions. In North America the focus is on life-extensions of existing power stations. Irrespective of new build or refurbishment plans nuclear power continues to play an important role as a base-load generator with carbon emissions rated below that of natural gas or even solar power [source: NRCAN 2015]. Since the accident at the Fukushima nuclear power plant in Japan in March 2011, the topic of nuclear safety and severe accident mitigation have dominated activity within the field of nuclear engineering. In order to make transformative changes in nuclear safety we must innovate our nuclear power technologies. While next-generation concepts such as GEN-IV reactor designs have given rise to substantive changes for future new-reactor builds, they cannot change the basic features of existing plants which may have 30-60 years of additional generation life. The objective of this research program is to develop and test new nuclear fuel concepts, known as accident tolerant fuels (ATF), to radically improve safety in existing operating reactors.***Within the nuclear safety field, two metrics are predominantly used to evaluate safety characteristics: a) Core Damage - CD and b) Large Early Release - LER. Postulated events that cause fuel melting/dislocation are classified as potential CD events. Extreme events that may release radioactivity to the environment and with insufficient time for implementation of emergency measures are termed LER. This Discovery Grant examines new Accident Tolerant Fuels with the following characteristics:***a) Better heat transfer such that margins to sheath and fuel failures are significantly increased thereby reducing the probability of CD.***b) Improved retention of radio nuclides in the event of fuel failures (those that occur both chronically during normal operation and in particular during a nuclear event), thereby reducing the amount of radiological inventory which might be released in an accident.***c) Avoid the rapid-oxidization reactions which give rise to hydrogen production during CD events, thereby preventing hydrogen detonations which may cause the event to progress to a LER.***Based on the results of over 10 years of research on nano-particle heat transfer and nuclear safety, I believe the best potential ATF may involve a hybrid of nano-structured materials and nuclear fuels. In the available literature only 1 paper was found examining the potential improvement to the Canadian CANDU design, and the focus of that work was Plutonium mixed-oxide fuels, and not on the existing fuel supply chain (natural to slightly enriched Uranium). This work will provide a firm basis for ATF concepts and will generate HQP with knowledge in this emerging area.