“The small modular reactor has been the nuclear industry’s favorite slide for about a decade. Utilities pitch it, governments model it, conference panels argue about it, and for years that was as far as it got in the Western world: a promising design nobody had actually built at the scale of a power grid. Then this spring, a crane in Ontario lowered a 953-tonne slab of steel and concrete into a shaft 35 meters deep and quietly ended the talking phase…

The press releases lean hard on the word ‘first,’ so it helps to pin down which kind of first you are looking at. Both OPG and GE Vernova are careful to say Western world’s first, or G7’s first, grid-scale SMR, and that scoping matters. Russia and China already operate small modular reactors, and Argentina has a pilot under construction, so this is not the first SMR on Earth. It is the first one a G7 country has built and wired to a major grid.

It is also a different machine from the other advanced-reactor projects breaking ground right now. Bill Gates’ TerraPower just started building a sodium-cooled reactor in Wyoming, and a company in Italy is testing a full-scale lead-cooled rig with electric heaters standing in for the fuel. Those are fast reactors chasing exotic coolants. The BWRX-300 is the opposite bet: a deliberately conventional, water-cooled reactor scaled down and built in a factory-style sequence, designed to be boring and repeatable rather than novel. And none of this is making electricity yet. OPG is targeting the end of 2030 for grid connection, with construction itself wrapping up around 2029.”

From Autonoción.