The construction of Canada’s first new nuclear reactor in over 30 years has officially commenced on the north shore of Lake Ontario. In a significant milestone reached in late April, the Ontario government announced the placement of the reactor’s foundation, which was lowered into a 35-metre-deep vertical shaft by one of the world’s largest crawler cranes. This foundation, weighing more than 950 tonnes—equivalent to the weight of three Airbus A380s—marks the start of a challenging journey for Ontario Power Generation (OPG) and its partners as they work towards completing the Darlington small modular reactor (SMR) by the end of 2030.
A Clock is Ticking
With the foundation now laid, the countdown has begun. For OPG, the Darlington SMR has been under construction for nearly a year, but according to industry standards, the official construction phase is only recognised when the concrete foundation is poured. OPG, in collaboration with GE Vernova Hitachi Nuclear Energy, Aecon Group Inc., and AtkinsRéalis Group Inc., has a tight timeline of just four years and seven months to finish the project and connect it to the electrical grid. Once operational, this new reactor could generate enough electricity to power approximately 300,000 homes, making it a crucial component of Ontario’s ambitious energy strategy that anticipates more reactors in the years ahead.
Challenges Ahead
The construction of the Darlington SMR is no small feat. On any given day, the site may host as many as 1,500 workers, all focused on a complex set of tasks. OPG’s responsibilities include building the first-ever BWRX-300 reactor, along with a robust containment facility, a control building housing the main control room, and a structure for the turbine generator. Additional support structures will be necessary, comprising a water cooling system with underground tunnels and a switchyard.
Historically, the construction of nuclear reactors has proven to be a lengthy and intricate process. The last nuclear plant completed in Canada was over 30 years ago, and the 25 Candu reactors that were built from 1958 to 1985 took, on average, more than seven years to reach commercial operations. The Darlington SMR serves as a prototype, akin to the Douglas Point reactor constructed in the 1960s, which took 8½ years to build.
Global Context and Comparison
In the global landscape, China’s dominance in nuclear construction is evident, with 44 of the 75 reactors that began construction since 2016 located there. However, even in China, few reactors are finished within five years. In contrast, the Western world has witnessed a series of delays and cost overruns with its nuclear projects. Only two reactors have been completed in the past four decades, both in the United States, and even those faced significant delays.
The reasons behind such setbacks are numerous, ranging from incomplete engineering designs at the outset to quality control issues during construction. The V.C. Summer units in South Carolina, for example, began construction without a complete set of blueprints, leading to costly reworks and disputes.
OPG’s Optimism and Strategy
Despite the challenges that lie ahead, OPG exudes confidence in the capabilities of the BWRX-300, touted as the simplest boiling water reactor yet. This design is based on mature American technology, with over 100 reactors currently in operation worldwide, which lends credibility to its foundational principles.
To expedite the construction process, OPG plans to employ modular building techniques. The base mat for the Darlington SMR, for instance, consists of 56 sections that were pre-manufactured off-site and then assembled on-site. This method is expected to enhance efficiency and reduce the risk of delays. Furthermore, OPG aims to use standardised components, such as the turbine and generator, to streamline the project.
An “integrated project delivery contract model” will also be utilised, encouraging collaboration among stakeholders and promoting shared risk and rewards, which is critical in navigating unforeseen challenges.
Why it Matters
The successful completion of the Darlington SMR is pivotal not only for Ontario’s energy strategy but also for the future of nuclear technology in Canada and beyond. As the only remaining SMR project from a decade of promises, its outcome will likely influence global perceptions of small modular reactors, which are marketed as quicker and more cost-effective alternatives to traditional large reactors. If OPG can deliver on time and on budget, it may set a precedent that revitalises interest and investment in nuclear power worldwide. Conversely, failure could stall further nuclear developments and reshape energy policies both domestically and abroad, highlighting the stakes involved in this landmark project.
