Accident tolerant fuel completes first lifecycle at the Vogtle Nuclear Power Plant.

[NNadir]

Accident tolerant fuel completes first lifecycle at Vogtle

Framatome’s enhanced accident tolerant fuel assemblies recently completed a third 18-month fuel cycle at Southern Nuclear’s Vogtle-2 plant—the first of this type of fuel to reach this milestone in the U.S., the company said.

Framatome’s GAIA fuel assemblies with Protect enhanced accident tolerant fuel (EATF) technology have operated over four and a half years since being inserted in 2019 at Vogtle, which concludes the full timeline assessment of the lead fuel assemblies concept and supports licensing activities to achieve market readiness.

“This is a significant milestone for our program, and through our collaboration with the U.S. Department of Energy and Southern Nuclear we bring this new and innovative technology one step closer to commercial operations,” said Lionel Gaiffe, senior executive vice president for the Fuel Business Unit at Framatome. “The success of this project demonstrates accident tolerant fuel readiness for the safe and reliable generation of our clean energy future...

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The reactors at the big bogeyman at Fukushima failed because of a hydrogen explosion resulting from the steam oxidation of the zirconium cladding in the fuels when the heat removal was interrupted because of the inundation of the back up diesel generators. (A similar occurrence took place at Three Mile Island, but the hydrogen was vented, preventing a hydrogen explosion.) The new fuels are an approach to engineering away this risk in the future.

The trick in this accident tolerant fuel as I understand it, if I recall correctly is to place a think layer of a chromium alloy on the surface of the fuel to prevent the formation of hydrogen according to the high temperature reaction with steam:

Zr + 2H₂O_(g) -> ZrO₂ + 2H_2(g)