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Rickover's quote on new reactors vs existing ones is apt to every development in this field. Sodium cooling is temperamental with the US navy abandoning it due

by wbl 6y ago

Rickover's quote on new reactors vs existing ones is apt to every development in this field. Sodium cooling is temperamental with the US navy abandoning it due to leak problems, and France having mixed experiences. The coolent catching fire whenever it leaks is not so fun. Fast spectrum with metallic fuel and pyroprocessing was demonstrated in the IFR but is messier than you might naively expect, with leaks of xenon that need control. The HEU for startup is also problematic but maybe derated plutonium could be used.

jabl 6y ago
> Rickover's quote on new reactors vs existing ones is apt to every development in this field. Indeed, it's easy to get carried away by the promises of new exiting tech on the horizon. Then again, we're never going to innovate if we expect everything new to immediately prove superior economics. > Sodium cooling is temperamental with the US navy abandoning it due to leak problems, and France having mixed experiences. The coolent catching fire whenever it leaks is not so fun. Indeed, sodium has downsides. As well as upsides, which is why most fast reactor designs to date have used it as coolant. > Fast spectrum with metallic fuel and pyroprocessing was demonstrated in the IFR but is messier than you might naively expect, with leaks of xenon that need control. Well, isn't that true for all reprocessing? When you crush or otherwise process the spent fuel, the radioactive noble gases will escape. > The HEU for startup is also problematic but maybe derated plutonium could be used. HEU for civilian applications is non-viable, I think. Modern fast reactor designs are designed to work with HALEU, before (potentially) switching to a U-Pu closed cycle. One can of course quibble where to draw the line between HEU and HALEU. The current 20% is certainly a conservative choice. But it's also a quite minor hill to die on.

by wbl 6y ago

jabl 6y ago

> Rickover's quote on new reactors vs existing ones is apt to every development in this field. Indeed, it's easy to get carried away by the promises of new exiting tech on the horizon. Then again, we're never going to innovate if we expect everything new to immediately prove superior economics. > Sodium cooling is temperamental with the US navy abandoning it due to leak problems, and France having mixed experiences. The coolent catching fire whenever it leaks is not so fun. Indeed, sodium has downsides. As well as upsides, which is why most fast reactor designs to date have used it as coolant. > Fast spectrum with metallic fuel and pyroprocessing was demonstrated in the IFR but is messier than you might naively expect, with leaks of xenon that need control. Well, isn't that true for all reprocessing? When you crush or otherwise process the spent fuel, the radioactive noble gases will escape. > The HEU for startup is also problematic but maybe derated plutonium could be used. HEU for civilian applications is non-viable, I think. Modern fast reactor designs are designed to work with HALEU, before (potentially) switching to a U-Pu closed cycle. One can of course quibble where to draw the line between HEU and HALEU. The current 20% is certainly a conservative choice. But it's also a quite minor hill to die on.