Canada's CANDU Strategy: The Nuclear Fuel Advantage for Newcomer Markets
Every country building its first nuclear power plant eventually runs into the same practical problem: enriched uranium fuel requires access to enrichment services, and enrichment capacity sits in the hands of a small number of countries, mainly Russia, the United States, France, and China. A newcomer market negotiating a reactor purchase is also negotiating, whether it realizes it fully at the outset or not, a long-term dependency on whichever country supplies its enriched fuel. Canada's CANDU reactor design was built around a different answer to that problem, and it is worth examining on its own, separate from anything else Canada's nuclear industry is doing.
A Design Choice Made for a Different Reason That Solves Today's Problem
CANDU reactors run on natural uranium, not enriched uranium. This was originally a Canadian design decision made in the 1950s to avoid needing enrichment infrastructure at all, using heavy water as the moderator instead to make natural uranium fission efficiently. The tradeoff was the added cost of producing heavy water, offset by savings from skipping the enrichment step entirely and by lower reactor downtime for refuelling.
For a country building its first nuclear programme today, this tradeoff lands very differently than it did when Canada first made the choice. A newcomer market does not need to secure a long-term enrichment supply contract, does not need to build political or commercial dependency on an enrichment-holding state to keep its reactor fuelled, and does not have to factor enrichment services into its geopolitical risk calculation the way it would with a light-water reactor design. The natural uranium fuel cycle removes an entire category of external dependency from the country's energy security planning, at the cost of a domestic fuel fabrication step that Canada has already shown can be run economically, since Canadian fuel fabrication plants convert Canadian-refined uranium dioxide directly into CANDU fuel bundles without any enrichment process involved.
The Track Record Already Exists
This is not a theoretical advantage. Twelve CANDU units have already been sold and built outside Canada, in South Korea, Romania, India, Pakistan, Argentina, and China, along with the engineering expertise to build and operate them, and 25 CANDU reactors are operating today across five countries.
The Enhanced CANDU 6 (EC6) represents one of the newest generations of CANDU reactor designs, referencing technology deployed at Qinshan in China. Following its corporate restructuring, Candu Energy pursued new build deployment opportunities for the EC6 model alongside receiving Canadian government development funding to support the completion of the EC6 development program. In late 2023, Canadian firm AtkinsRéalis introduced a new Candu Monark design, a 1000 MWe unit with passive safety features that is currently going through a preliminary regulatory design assessment with Canada's nuclear regulator, using the refurbished Darlington plant as its reference facility. In March 2026, Candu Energy signed a memorandum of understanding with Türkiye Nuclear Energy Company (TÜNAŞ) to assess deployment of the design there, a live example of the natural uranium fuel cycle being evaluated by a market outside Canada's existing customer base.
Fuel Cycle Flexibility Beyond the Enrichment Question
CANDU designs are being adapted to run on alternative fuels, such as recycled uranium from light-water reactors, allowing them to complement light-water reactor operations rather than compete directly with pressurized and boiling water designs. To support this fuel adaptability, Candu Energy entered into agreements in 2012 and 2016 with China National Nuclear Corporation and other partners to finalize the design and build the Advanced Fuel CANDU Reactor (AFCR).
For a country that already operates, or plans to operate, light-water reactors from another vendor alongside a CANDU unit, this creates a second-order benefit. A country's spent fuel from its light-water reactors can be adapted into a usable fuel source for CANDU units, allowing CANDU designs to complement operators of pressurized and boiling water reactors abroad rather than compete with them.
What This Means for a Business Evaluating the Market
For a firm assessing where Canada's nuclear industry fits into a newcomer market's vendor decision, the natural uranium fuel cycle is a genuine point of differentiation that exists independently of reactor price, construction timeline, or financing terms, the criteria that usually dominate vendor comparisons. A country weighing energy security risk as part of its nuclear decision has a concrete, already-proven reason to give the CANDU family serious consideration, beyond whatever commercial terms a given bid includes. The relevant diligence question for any market evaluating its first or next reactor is not only which vendor offers the best financing or the fastest construction schedule, but which vendor removes the fewest or the most future dependencies from the country's own energy security position, and Canada's fuel cycle answer to that question has thirty years of operating history behind it in markets that started, as many of today's emerging nuclear buyers are starting now, with no enrichment access of their own.
