Actually, Toshiba has been working on this for about a decade. It is a pretty cool idea. It is inheritely safe, due to a sliding neutron reflector used to sustain the chain reaction in the core. The reflector is heat controlled, when it is hot enough, it stops. When it cools, it slides down until it gets hot again. Simple and elegant.
The whole reactor is a cylinder, with 2 pipes coming out of it. One for water in, and one for steam out. There is no need for personnel to run it. Once it is turned on, it stays on until it is exhausted, in 40 years. Security would not be a problem, because you build a bunker with a whopping concrete lid, and slip it in, and drop the lid on. No maintenance, no repairs, and secure. When it is used up, you pull the entire thing out and ship it back.
You would have to have a steam turbine and power generators, along with the afore mentioned building, people, and maintain and repair that, though. I never said that it was a free lunch.
> Actually, Toshiba has been working on this for about a decade. It is a pretty cool idea.
Yes, I know. I’ve been following the announcements for some time. However, 200 kilowatts is the smallest reactor they have ever discussed - 50 times smaller than the 10 megawatt models that I have usually seen mentioned.
The power output of this reactor is minuscule. One horsepower equals 746 watts, so 200 kilowatts is only about 269 horsepower. The reactor core itself is designed to require no maintenance over its entire 350,000 hour continuous operating life, but I doubt you will be able to find a 270 horsepower steam turbine or AC generator which is designed to be completely maintenance-free for 40 years of 24/7 operation.
The reactor may be designed to require no onsite staff, but good luck getting the NRC to allow you to operate a reactor without one.
A simple “large concrete bunker” may seem like enough security, but will that be enough to protect the core if some jihadists dig a 500 meter tunnel to the closest point outside the concrete and set off a couple of tons of high explosive against it?