Uranium has two to three million times the energy density of coal, so one kg of uranium equals several thousand metric tons of coal.
I imagine a pellet is no larger than a marble, so it seems same proportion.
Relevant xkcd: https://www.xkcd.com/1162/
It is hard to get away from that energy density, yeah. I remember seeing an old black and white photo in a book as a child where each pellet of uranium was equal to like a ton of coal in terms of electrical production.