The global push for carbon neutral and zero-emissions power generation has brought renewed interest in nuclear power, particularly for smaller units that are scalable and in some cases mobile, able to provide power in remote areas.

Analysts say smaller nuclear reactors are more cost-effective, as they’re considered a more manageable investment for power generators as opposed to construction of large reactors. They also can help repurpose retiring fossil fuel generation, with small modular reactors (SMRs) able to be positioned at brownfield sites such as decommissioned coal-fired power plants.

Learn more about Canada’s nuclear power program and its role in advancing global nuclear technology.

X-energy, a Maryland-based nuclear reactor and fuel design engineering company, is among several groups developing nuclear technologies to serve a host of purposes, from power generation to space travel. The company manufactures TRISO-X, its own proprietary version of tri-structural isotropic (TRISO) particle fuel. Its Xe-100 reactor is a Gen-IV high-temperature gas-cooled reactor (HTGR), in this case an 80-MWe reactor that can be scaled into what X-energy calls a “four-pack” 320-MWe power plant.


The company says the modular design of the reactor means installations can scale up as needed, to provide more electricity. X-energy in 2019 signed a deal with Jordan to provide that country with its technology.

Katherine Moshonas Cole, president of X-energy Canada, recently spoke with POWER about the company’s technology and how it fits with Canada’s burgeoning nuclear power program. Cole has served as an executive board member of the Canadian Nuclear Association (CNA) and chair of the Regulatory Affairs Advisory Committee of the CNA.

POWER: X-energy has said the 80-MWe reactors can be scaled up to a 320-MWe plant. Are there any sites that have been identified, or are being considered, to receive the Xe-100 reactor(s)?

Cole: X-energy is actively working toward the opportunity to site our Xe-100 four-pack in Canada at the OPG Darlington site in Clarington, Ontario. After a tremendously rigorous due diligence process in the second quarter of 2020, Ontario Power Generation (OPG) selected X-energy and our Xe-100 as one of three technologies to further consider for siting at Darlington.

Katherine Moshonas Cole is president of X-energy Canada.

We continue to make significant progress on all our commitments to Canada’s SMR Action Plan, supporting the federal government’s pan-Canadian strategy in the development and deployment of SMRs across the country. Central to our efforts is building strategic partnerships and supply chain; engaging with the CNSC [Canadian Nuclear Safety Commission] and the Nuclear Waste Management Organization; promoting diversity in the emerging SMR workforce; and building meaningful relationships with our stakeholders, including Indigenous communities.

Outside of Canada, the U.S. Dept. of Energy [DOE] selected X-energy in October 2020 as part of the DOE’s Advanced Reactor Demonstration Program [ARDP]. This program is designed to spur domestic private industry to demonstrate advanced reactors in the United States. The DOE will invest approximately $1.23 billion to this $2.5 billion project, enabling us to build the world’s first commercial scale advanced nuclear reactor with Energy Northwest in Washington state by 2027. In March, X-energy signed a cooperation agreement that officially begins our participation in the ARDP. (Editor’s note: The DOE chose more projects for the ARDP program in December 2020.)

POWER: Does X-energy have a target date to have the Xe-100 in commercial operation (recognizing design approval, etc.)?

Cole: In Canada, we are focused to have our first Xe‑100 in commercial operation by 2028.

We are working closely with our partners in the U.S. and Canada to advance the design, engineering, analysis, and licensing work for the Xe-100. X-energy is engaged in two regulatory streams with the U.S. National Regulatory Commission and the CNSC.

X-energy plans to have its first Xe-100 reactor in commercial operation by 2028. Courtesy: X-energy

We have made significant progress in a CNSC pre-licensing Vendor Design Review (VDR), where we are providing submissions to demonstrate X-energy’s and the Xe-100’s alignment with Canadian regulatory requirements. We recently submitted our second VDR Focus Area package, providing documents in 12 focus areas, including a complete submission on our TRISO-X fuel design and development.

POWER: How important is the Xe-100 to Canada’s nuclear power industry?

Cole: It is critical for Canada’s nuclear industry to get behind a technology that has the potential for long-term sustained growth. The Xe-100 is founded on true Generation IV technology: a high-temperature gas reactor using robust TRISO fuel. The future of nuclear power depends on remarkably safe, simple, and scalable reactor designs like the Xe-100, and it is important that Canada join as an early mover. Deploying an Xe-100 in Canada will provide a fantastic opportunity for Canada’s well-exercised nuclear industry to participate at the ground level and be at the forefront of delivering this SMR technology nationally and beyond, for many years.

We are leveraging years of advancement in Gen-IV HTGR technology with numerous innovations for economic, environmental and safety benefits. Deployment of the Xe-100 will support Canada’s goals relative to the economy, skills development, environment, and climate goals.

We also manufacture our own proprietary nuclear fuel, TRISO-X, to ensure supply and quality control. Called “the most robust nuclear fuel on Earth” by the DOE, our TRISO-X fuel leverages 40-plus years of prototype and full-scale demonstration. We aspire to site a commercial fuel fabrication facility in Canada to supply our Canadian fleet of reactors. We see this as an exciting opportunity to create greater economic value inside Canada to our abundant uranium resources.

POWER: How important is the Xe-100 to supporting renewable power integration to the grid?

Cole: The Xe-100 design is ideal as the linchpin in an integrated energy system. It can pair up with renewable power, providing stability during times of intermittent generation as it load-follows effortlessly, adjusting power output by 5% per minute between 40% to 100% full power, as demand for electricity fluctuates. Alternatively, the excess power, in the form of high-quality 565 degrees C steam, can be used for alternative uses such as hydrogen generation, process heat applications, mining, and more. This technology is remarkably adaptable as the safety and performance of the reactor is not coupled to the downstream application.  

Darrell Proctor is associate editor for POWER (@POWERmagazine).