The NRC approval of a NuScale design is an important milestone for new nuclear power. The design features failsafe capabilities:
- The control rods which stop the chain reaction are not lowered by power. Instead they are held up with power and fall down without power, turning the reactor off.
- The cooling is by immersion in water which cools by convection. The water near the reactor warms and rises, moves to the side where it cools and falls, thus cycling around without the need of power.
For a nuclear powered ship we will use seawater to quickly cool the inner (pure) water, so that not as much is required normally. Power would be used to pump the seawater out, so that the ship doesn't carry more than needed, but when the power is cut the seawater will fill a space so that there is enough to do power-free cooling, as above.
I'm a supporter of CANZUK, in fact I independently invented the acronym before I knew other had beaten me to it (seven years ago: https://grampsgrumps.blogspot.com/2015/05/the-canzuk-solution.html). However we'll leave NZ out of the following because they are so anti-nuclear. Let us consider a CANAUSUK federation of Canada, Australia and the UK. Our united country might well be called The Maritime Kingdom, or Maritimia.
Maritimia is a natural ally of the US, but it is a parlimentary democracy and Kingdom. It is well connected by Internet and air transport, but to move substantial physical stuff around it would be nice if sea transport was faster and carbon-free. The ideal solution is nuclear powered shipping. A nice advantage that Maritimia has, is that it is not opposed to government led commercial activity. Indeed I think public acceptance of nuclear shipping will be enhanced if it was under the direct control of the well-trusted CANAUSUK governments,
Beyond that, the whole world will be well served by nuclear shipping free of carbon and other pollution. The CANAUSUK governments are well respected and I think many places would be comfortable using nuclear shipping from such a confederation government. Shipping is a part of the world's CO2 problem, and this is a way to address it.