For about four years now we've been covering modular nuclear reactors in the "base load" section of our basic sustainability course, and in more detail in the energy course.
But even though this technology has been in the pipeline for quite a while, to my knowledge there has been no actual implementation.
Which is a great pity, because some of the modular technology is ground-breaking. Small nuclear reactors, using much safer fuel and more fail-safe systems than the larger commercial plants currently used, might easily be the ticket that lets us harden, decentralize, and smarten-up the aging grid, while providing the back-up power needed to make sense out of decentralized "rooftop" solar and offshore or land-based wind.
The new federal budget is out, in draft form, and $500m is being asked for to bring one or more modular technologies to the next scale, essentially to bring it through the "valley of death" whereby new ideas fail because private venture capital can't be convinced to back it in sufficient amounts.
Hopefully, Congress can be convinced to leave this relatively small program alone.