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Small Modular Reactors or CANDUs? Why not both?

Among the ongoing debates about how to develop a clean energy system that will be able to support a net zero carbon emissions society is whether to build many small modular reactors (SMRs) or fewer full-sized nuclear generating stations like the ones Ontario has today. Looking toward a future that will need at least double the amount of electricity available today, the answer is that Ontario needs both.

SMRs benefit from being manufactured off site and assembled relatively easily, requiring less space to operate, and having standardized operating and maintenance procedures that make them less costly to keep in service. Providing just 300 MW of power each (less than 10% of Pickering Nuclear Generating Station’s capacity), SMRs are ideally suited to powering major industrial sites like mines and remote communities. SMRs can also adjust the amount of energy they produce more quickly than a traditional nuclear reactor so they have the potential to replace natural gas as a suitable back-up for wind or solar power.

Full-sized generating stations, on the other hand, are the workhorses of Ontario’s energy system and will continue to be in the future. With more than 50 years in commercial operation, made-in-Canada CANDU reactors have an established local supply chain and workforce to support them. The refurbishment projects underway at Bruce and Darlington Nuclear Generating Stations have demonstrated that major nuclear infrastructure can be built on time and on budget. While each 300 MW SMR would need to go through its own lengthy regulatory process to gain approval, one full-size generating station of 3,000 to 6,500 MW could be approved in a single regulatory process.

SMRs and new, full-sized CANDU generating stations both have their place in a net zero emissions Ontario. The key is to move forward as quickly as possible with both technologies to limit the need for natural gas power in the medium- and long-term.

Read the full Nuclear Power white paper