Does the S Still Stand for Small?

Small modular reactors (SMRs), designed to be faster to build and easier to site, have long been touted as a replacement for conventional reactors. SMRs—the International Atomic Energy Agency classifies the technology as reactors generating less than 300 MW of electricity—are conceived as a means to make nuclear power simpler and less challenging to add to the grid. But questions remain as to just what size is optimal for SMRs.