I remember that Toshiba was/is developping a nuclear electricity generator, a box 2x2 meters (or so), completely sealed, which provides energy in remote location. After about 20 years, the box supposed to be returned for decomission. No maintenance required.

I was seriously interested to buy one to put it under my garden, but:

- the output is constant and difficult to manage, so it would also require to build a swimming pool to direct the extra output there and hope it would not boil, or convince surrounding residents to join the local nuclear club.

- it was more expensive than to be on a grid

- local nuclear agencies would likely raise its concern to have an unsecured nuclear asset in a residental area. Not to mention, that fellow resident were not too exited about a prospect having sort of nuclear power station just down the road.

But army is a different categoy :-)