"NuScale uses a light water reactor—by far the most common type of reactor in commercial nuclear power plants—but that’s about where the similarities end. NuScale’s reactor is 65 feet tall and 9 feet in diameter, and is housed in a containment vessel only slightly larger. About the size of two school buses stacked end to end, you could fit around 100 of them in the containment chamber of a large conventional reactor. Yet this small reactor can crank out 60 megawatts of energy, which is about one-tenth the smallest operational reactor in the US today."
https://www.wired.com/story/the-next-nuclear-plants-will-be-small-svelte-and-safer/
https://www.wired.com/story/the-next-nuclear-plants-will-be-small-svelte-and-safer/