Despite Ontario’s relatively cheap electricity supply (fourth lowest in Canada), our thirst for energy is rapidly expanding. A new report by the province’s Independent Electricity System Operator (IESO) projects Ontario’s electricity demand will grow by 60 per cent by 2050. This means we need to develop additional sources of power – and the clock is ticking.

One promising solution is the advent of small modular reactors (SMRs) and microreactors: emerging technologies that produce lesser amounts of power than traditional nuclear plants like those on the Great Lakes such as at Bruce Power or Ontario Power Generation’s (OPG) Pickering and Darlington facilities. The world’s first 300 megawatt SMR (designed by GE Hitachi Nuclear Energy) is scheduled to be operational at the OPG Darlington Nuclear Generating Station before the end of the decade. Other SMRs are expected to be brought online in Canada and around the world in the 2030s, and beyond.

How big is ‘small’?

Very small SMRs (microreactors), roughly the size of a semi-trailer on a site about the size of a football field, offer the advantages of being deployable almost anywhere and serving smaller, remote communities, or even power a hospital. Some SMRs can adjust power input as system demand fluctuates.

Individual SMRs produce just a small fraction of electricity compared to traditional CANDU-based nuclear plants. But, if you build enough of them to complement the existing nuclear infrastructure, and place them strategically, over time you will have the added capacity needed to meet Ontario’s and Canada’s soaring power demands. Ontario Tech University will play a key role in this energy transition.

Ontario Tech receives national funding to study SMR fuel performance

On May 7, the Natural Sciences and Engineering Research Council of Canada (NSERC) and Natural Resources Canada (NRCan) awarded a new research grant to Ontario Tech to develop a gamma-ray imaging system to examine SMR fuels and materials. Through a four-year special NSERC Alliance-NRCan joint partnership grant (valued at $537,900), Dr. Kirk Atkinson of the Faculty of Engineering and Applied Science, and Director of Ontario Tech’s Centre for Small Modular Reactors, will assess SMR fuel composition and integrity.

“We need to understand the long-term performance and behaviour of these newer uranium fuels, which are somewhat different from those used in traditional CANDU reactors,” says Dr. Atkinson. “This grant will help us establish the tools and capability needed to confirm predictions and assure safety.”

Dubbed ‘RIDGEBACK 2’ the university’s gamma-ray imaging system won’t generate or emit radiation itself, rather just measure it in a special way. The imaging system will be smaller than a person, and developed on campus, in the Centre for SMRs, housed in Ontario Tech’s Energy Research Centre.

“Gamma rays are routinely studied in medical scans in nuclear medicine,” explains Dr. Atkinson. “Patients are injected with a radioactive substance and technicians measure the gamma rays emitted and construct images of body structures and functions to figure out if people are healthy or not. Similarly, used nuclear fuel contains radioactive fission products from which we can detect gamma rays and create images to check the fuel’s behaviour.”

While traditional CANDU reactors use natural enrichment fuel, SMRs like the one that will be deployed in the coming years at Darlington uses conventional low-enriched uranium fuel, which is somewhat novel in Canada.

“Understanding, monitoring, inspecting, and verifying these new-to-Canada fuels is one of the impetuses of this grant. With fuel integrity, we are thinking about its shape and condition. We are talking about assuring there are no defects or leaks over time. With verification, we are confirming the fuel is what we think it is (that it hasn’t been tampered with) and that internally it is performing as we expect.”

Quote

“Professor Atkinson’s new research project is an outstanding example of Ontario Tech’s energy leadership: to find innovative solutions to foundational societal problems and challenges. The university is grateful to NSERC and NRCan for its continued support of our important research in nuclear energy, as Canada’s energy sector transitions to net-zero carbon emissions.”
-Dr. Les Jacobs, Vice-President, Research and Innovation, Ontario Tech University

Nine questions with Dr. Kirk Atkinson, Director, Centre for Small Modular Reactors at Ontario Tech University

How much power does an SMR provide?

• A 1-megawatt electric (MWe) plant could produce enough power for say 1,000 homes; and a 10 MWe plant would serve about 10,000 homes. By comparison, Ontario’s current collective nuclear infrastructure generates about 13,000 MW of electrical power.

What does an SMR actually look like, compared to conventional nuclear reactors?

• It’s a spectrum, actually: SMRs come in many shapes and sizes, but the plant footprint is much smaller than a conventional reactor. SMRs are said to provide 300 MW of electricity or less. Microreactors are said to produce 10-to-20 MW or less of electricity. Smaller is possible. Some vendors have SMR designs that fit in a shipping container that could be transported by railcar or by truck.

Have SMRs been deployed anywhere before?

• Many naysayers claim SMRs haven’t been built yet so are unproven. However, SMRs have been made in factories and used safely in submarines and ships for decades, so there is nothing technically impossible about them.  

Do SMRs need cooling sources like conventional reactors?

• During operation, the smallest microreactors may cool passively, while larger SMRs may need active cooling (such as water or cooling fans). However, when a reactor shuts down, it is still hot, and initially still generating about one-tenth of its original power. This dissipates quickly over the following hours, days, and weeks, and where necessary, SMR designs have features that allow this heat to be lost in passive ways.  

How do SMRs connect with the grid? Do they complement existing infrastructure, replace it, or both?

• They can connect to the grid like any other electricity generating technology, or they could drive independent grids or microgrids in remote locations.

Will my electricity bills get more expensive with SMRs?

• Ontario has the fourth cheapest electricity in Canada, and it is about 60-per cent nuclear-powered. So, no, they don’t have to.

SMRs vary from the CANDU design because fuels are ‘enriched’ and each design uses a different type of fuel. Can you explain enrichment?

• Think about it like concentrated orange juice. Orange juice has water in it. If you remove some water it becomes more concentrated. Natural uranium has two parts: the energy-useful Uranium-235 isotope (0.7 per cent) and the less useful Uranium-238 isotope (99.3 per cent). Enrichment processes reduce the amount of U238 relative to U235. This doesn’t happen in Canada at the moment.
• Enrichment to 5 per cent U-235 is typical in the United States today, but some of these SMRs/microreactors will use ‘High Assay Low Enriched Uranium Fuel’ (HALEU) fuel, perhaps up to 19.75 per cent enrichment. Above 20 per cent enrichment is not allowed to avert risk of nuclear weapons proliferation. The supply chain for HALEU at the quantities needed for SMRs is in its infancy.

How long does SMR fuel last vs conventional reactors?

Reactors fueled with enriched fuels typically need refueling every few years. Some SMRs will have the same, others perhaps 5 or 10 years, depending on the design. CANDU reactors need refueling while they are online.

Is spent SMR fuel safe?

• It’s no less safe than how used fuel is stored around the world today.

Media contact
Bryan Oliver
Communications and Marketing
Ontario Tech University
289.928.3653 (mobile)
bryan.oliver@ontariotechu.ca