On the contrary, you gain economies of scale. The way the economies of scale work is if you build n identical widgets, it costs you less than n times the cost of building one single widgets. In other words the unit cost of a widget goes down as the number of produced widgets increases.
If you want to produce a bigger widget though, you generally have diseconomies of scale. For example the Saturn V rocket was about 20 times bigger than the Titan 2 rocket (from which it was derived) but cost about 60 times more.
So, if a Gigawatt-size nuclear power plant is too expensive to build, you build 20 plants of 50 MW each. This is how you achieve economies of scale.
I'm not sure if the goals for this project are the same, or if the goal of a low-maintenance reactor are even possible, but it sounded pretty cool.