As the world looks to meet rising energy needs, a small but powerful nuclear technology has taken centre stage: small modular reactors (SMRs).  

SMRs are driving a new era for the nuclear industry but putting them into widespread use will require overcoming complex challenges. At McMaster, researchers are tackling some of the key questions shaping SMR deployment globally, from mitigating corrosion in reactor components and strengthening containment structures to managing waste and exploring the business case for SMRs. 

Advancing sustainable materials solutions for SMRs

As with any new technology, SMRs come with a host of materials challenges, explains Materials Science and Engineering professor Joey Kish. 

Unlike traditional nuclear reactors, SMR components can be factory-made, which simplifies deployment, especially in smaller, northern and remote communities. There are several kinds of SMRs, including molten-salt reactors, which use hot liquid salt instead of water to carry the heat required to generate energy. 

While molten-salt reactors are attractive for their efficiency, enhanced safety features and potential for modular deployment, corrosion remains a major materials challenge. 

“The high temperatures in these reactors, the high levels of radiation and the chemistry of the molten-salt coolant can all exacerbate corrosion,” explains Kish. 

His lab aims to develop strong, corrosion-resistant metallic components that can withstand the demanding conditions inside these reactors.   

His research team is getting ready to use a hot cell at the McMaster Nuclear Reactor to see how materials in molten-salt reactors corrode over time while being exposed to gamma radiation.    

They’re also looking ahead to SMR decommissioning and waste management. With $1.4 million in support from the Canadian government, Kish’s team is developing a safe, eco-friendly and cost-effective laser decontamination technology that can significantly reduce metallic waste. 

Having nuclear facilities on campus means his team can test their solutions in real radiation environments, and students gain unique hands-on research experience, says Kish. 

“We’re really making the most of the resources and talent we have on campus to move this research forward. That’s the really cool part of it — the big players in the future of this industry could be people that we helped train here at McMaster.” 

Optimizing concrete for more resilient nuclear infrastructure

Materials science isn’t the only discipline at McMaster turning its focus to nuclear.  

Ousmane Hisseine, assistant professor of Civil Engineering, is developing sustainable and resilient concrete solutions for nuclear infrastructure projects, including SMRs. 

Concrete plays a major role in the nuclear energy supply chain, says Hisseine.  

“From the containment structures that enclose nuclear reactors, to the canisters used to safely store spent fuel, concrete is the ultimate physical safety barrier for nuclear facilities,” he says.  

Concrete is also cost-effective – the ingredients needed to make it are non-toxic, highly abundant and found in the earth’s crust.    

Hisseine’s research team is developing what they’ve coined Damage-Tolerant Radiation-Shielding Ultra-High-Performance Concrete or DT-RS-UHPC.  

Five times stronger than the concrete used in residential buildings, DT-RS-UHPC can withstand Canada’s toughest environmental conditions, including salt exposure and freeze-thaw cycles, making it particularly useful for SMRs that are deployed in the north and in underground containment structures. 

It’s also optimized for radiation shielding. Hisseine’s team has created PARSO (Particle-packing and Radiation Shielding Optimizer), a software tool that tests thousands of ingredient combinations to find the ideal DT-RS-UHPC recipe for shielding against different types of radiation while providing exceptional mechanical strength and durability. 

Funded as part of the federal government’s Small Modular Reactors Research Grant Initiative, the project opens new possibilities for safer, more versatile and highly damage-tolerant reactor containment structures, says Hisseine. 

“We’re developing materials, we’re developing the tools to optimize those materials, and we’re training students,” he says, noting that one PhD student and three master’s students have graduated through his research program, with all three master’s graduates now working in the nuclear sector. 

Building Canada’s SMR strategy

SMRs are not only a decision about Canada’s clean energy future, they’re also a business decision, says Goran Calic, associate professor of Strategic Management at McMaster’s DeGroote School of Business. 

The global race to deploy small modular reactors is well underway, notes Calic. In 2023, the Ontario government approved construction of four SMRs at the Darlington nuclear site, which could power up to 1.2 million homes and create up to 18,000 new jobs. 

Calic is exploring policy and supply chain challenges in the energy industry, with a specific focus on how the nuclear workforce must evolve to meet future demands. 

The federal government estimates that approximately 30 per cent of Canada’s nuclear workforce will retire over the next decade and that global demand for nuclear skills will require roughly 1.1 million new personnel by 2050. 

“We’re going to need more people to operate, maintain and regulate SMRs, and more people across the supply chain to support new nuclear builds across the country,” says Calic. 

On top of that, organizations will need help picking the right SMR technology.  With over 100 different SMR technologies out there, says Calic, it can be a challenge to pick the one best suited to a community.  

Calic’s lab develops project profiles to help those planning for SMR deployment anticipate the infrastructure, labour needs and costs involved. 

They’ve also harnessed AI to create a tool that helps nuclear operators stay up to date on the latest regulation requirements. 

“We’re hoping it can help the industry address regulatory compliance needs quicker, reducing costs and freeing up time to focus on further enhancing safety at nuclear facilities,” says Calic. 

From business and science to engineering and medicine, nuclear research at McMaster spans disciplines, and its hands-on education programs have trained thousands of alumni who now work in the nuclear industry.  

Read more about how McMaster is preparing the next generation of nuclear leaders.