[wafflemaker]

In many places in the world people don't live on ranches or in 1000 m² houses, but in 80-150 m² twin houses or even flats.

In such tighter conditions, you can easily have enough inhabitants per km² that it would justify building small mobile nuclear reactors.

Who would like to live next to a reactor if it can melt down? Well, you have reactors using fuel pellets locked in marbles that due to their diameter can never meltdown.