Will New Brunswick choose a ‘small, modular’ nuclear reactor that’s not small at all (among other problems)?

NB Power seems determined to build at least two experimental reactors at the Point Lepreau nuclear site, but their chosen designs are running into big problems.

One possible alternative is the reactor design Ontario Power Generation (OPG) hopes to build at the Darlington nuclear site on Lake Ontario. OPG is promoting it as a “small, modular” nuclear reactor.

Consider a building that soars 35 metres upwards and extends 38 metres below ground. That’s 10 stories up, 11 stories down. At 73 metres, that’s almost as tall as Brunswick Square in Saint John, or Assumption Place in Moncton, the tallest buildings in New Brunswick. Would you call such a structure small?

That’s the size of the new reactor design, the first so-called “Small Modular Nuclear Reactor” (SMNR) to be built in Canada, if the Canadian Nuclear Safety Commission gives OPG the go-ahead in January. It’s an American design by GE Hitachi that requires enriched uranium fuel – something Canada does not produce. If the reactor works, it will be the first time Canada will have to buy its uranium fuel from non-Canadian sources.

The new project, called the BWRX-300, is a “Boiling Water Reactor” (BWR), completely different from any reactor that has successfully operated in Canada before. Quebec tried a boiling water CANDU reactor several decades ago, but it flopped, running for only 180 days before it was shut down in 1986.

The Darlington BWR design is not yet complete. Its immediate predecessor was a BWR four times more powerful and ten times larger in volume, called the ESBWR. It was licensed for construction in the U.S. in 2011, the same year as the triple meltdown at Fukushima in Japan. The ESBWR design was withdrawn by the vendor and never built.

The BWRX-300 is a stripped-down version of ESBWR, which in turn was a simplified version of the first reactor that melted down in Japan in 2011. To shrink the size and cut the cost, the BWRX-300 eliminates several safety systems that were considered essential in its predecessors.

For example, BWRX-300 has no overpressure relief valves, no emergency core cooling system, no “core catcher” to prevent a molten core from melting through the floor of the building. Instead, it depends on a closed-loop “isolation condenser” system (ICS) to substitute for those missing features.

But is the ICS up to the job? During a 1970 nuclear accident, the ICS failed in a BWR at Humboldt Bay in California. At Fukushima, the ICS system failed after a few hours of on-and-off functioning.

Because CNSC, the Canadian nuclear regulator, has no experience with Boiling Water Reactors, it has partnered with the US Nuclear Regulatory Commission (NRC). They both met with the vendor GE-Hitachi several times.

The regulatory approach of the two countries has been very different: in February 2024, the U.S. NRC staff told GE-Hitachi that a complete design is needed before safety can be certified or any licence can be considered. But In Canada, the lack of a complete design seems no obstacle.

CNSC public hearings in November 2024 and January 2025 are aimed at giving OPG a “licence to construct” the BWRX-300 – before the design is even complete, and before the detailed questions from U.S. NRC staff have been addressed.

Building the BWRX-300 will require a work force of 1,000 or more. The entire reactor core, containing the reactor fuel and control mechanisms, will be in a subterranean cylindrical building immersed in water, not far from the shore of Lake Ontario.

There is nothing modular about this reactor. The idea that such an elaborate structure can just be trucked in, off-loaded, and ready to go, is a fantasy cultivated by the nuclear industry as a public relations gimmick.

The BWRX-300 will not be small. It will not be modular. And so far, its design is incomplete. An initial analysis of the design has identified unanswered safety questions.

If CNSC is prudent, it will not grant OPG a licence to construct the reactor next year. There are too many unanswered safety-related questions.

And if OPG is prudent, It will count on a doubling or tripling of the estimated cost. Already we have seen SMR projects in Idaho and Chalk River in Ontario run into crippling financial roadblocks.

The financial problems of the current SMNR designs in New Brunswick are the latest examples of private capital shunning nuclear investments. If New Brunswick is prudent, it will think very hard before diving into another nuclear boondoggle. The potential fallout will not be small at all.

Dr. Gordon Edwards is the president of the Canadian Coalition for Nuclear Responsibility based in Montreal.