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by rnhmjoj 480 days ago
> One common question is, why not fission? Fission works technically, but not practically. Small Modular Reactors (SMRs) could power ships, but licensing fission reactors on land is already brutally hard and expensive—doing it for vessels moving between international ports with enriched uranium is nearly impossible

What makes you think that licensing a fusion reactor will be easier? Safely handling tritium is fantastically more complicated that the fuel of a fission power plant.

Also, do you plan on breeding your fuel aboard the ship? If no, how do you plan to produce, store the tritium and refuel the ship? If yes, I'd like to know how you are planning to host the massive chemical plant to purify coolant, recycle unburt fuel, separate isotopes, detriatiate water and refuel that comes with your tokamak.

2 comments

Safely handling tritium is fantastically more complicated that the fuel of a fission power plant - I disagree with this, especially when considering the infinitely long HLW with fission fuel. Handling Tritium isn't easy but it's much more manageable.

Tritium breeding: we will have a FLiBe blanket and breed tritium, but we won't be processing and pulling out the Tritium on board, that will happen on land, so at port you drain the Tritiated FLiBe and replace it with Li-6 enriched FLiBe. There's a few companies working on the Tritium fuel cycle technology that are making great progress.

> infinitely long HLW with fission fuel

You don't have to process high level wastes on your ship, but you do with tritium. Even if you don't plant to extract the tritium from the blanket modules, you do need to recycle the unburnt fuel (the burn-up fraction is at best a few percent).

Tritium is radioactive hydrogen: it's a gas that explodes in air at low concetrations, it reacts with organic compunds, it has high mobility in pretty much any material, by decaying it produces Helium bubbles that can embrittle metals, its β radiation crack glasses etc.

unless you're the US Navy...