Ontario has just finished one of the most closely watched nuclear projects on the planet, and it did something critics often claim is impossible: it delivered a massive reactor overhaul early and below its approved budget. The completed work at the Darlington nuclear station is now locked in to provide decades of low‑carbon electricity at predictable prices, while keeping consumer bills in check. In a world struggling to decarbonize without driving up costs, the Darlington upgrade is a concrete demonstration that nuclear power can be both clean and affordable when projects are managed well.
What stands out is not only the engineering feat, but the way the project has been woven into Ontario’s broader economic and climate strategy. The refurbishment has extended the life of a major generating station, anchored a domestic supply chain, and set the stage for new technologies such as small modular reactors. Taken together, it offers a template for how other jurisdictions can pair nuclear investment with industrial policy to keep lights on and emissions down.
How Darlington was rebuilt, on time and under budget
The Darlington nuclear station east of Toronto has been a worksite for nearly a decade, as Ontario Power Generation, or OPG, undertook a full refurbishment of its four CANDU reactors. The utility describes the Darlington refurbishment as a multi‑year effort to replace key reactor components and modernize systems so the plant can operate safely for decades. Earlier planning documents projected roughly 30 million hours of work over about ten years, a scale that was underlined when initial estimates for Refurbishing Darlington were first laid out. The work ultimately involved taking each reactor offline in sequence, opening up the core, and replacing thousands of specialized components.
By early 2026, OPG announced that construction on the final unit was complete and that the four‑unit Project had wrapped up ahead of schedule. Detailed figures show that workers replaced 1,920 fuel channels and 3,840 feeder pipes, the kind of intricate, high‑precision tasks that typically drive up costs on nuclear projects. Instead, Ontario officials now say the refurbishment finished about $150 million under its approved budget, with some reports describing it as CAD150 million below plan.
Billions spent now to lock in cheap, clean power for decades
Refurbishing a nuclear station is never cheap, and Darlington was no exception, with the total cost of the work pegged at about $12.8-billion. Ontario officials emphasize that this $12.8 billion figure includes interest and cost escalation, which makes the under‑budget finish more striking. The payoff is long‑term: the work extends the station’s operating life to at least 2055, locking in a large block of non‑emitting baseload power for roughly three more decades. In a province where Nuclear power already supplies about 50 per cent of electricity, keeping that fleet running is central to both climate and affordability goals.
Officials in Ontario argue that the refurbishment is one of the most cost‑effective climate investments available, because it preserves a large asset instead of replacing it. The province’s own release on the project notes that the renewed station will continue to power up to 3.5 million homes and support an increasingly electrified economy, a point highlighted in the Content from CLARINGTON where Today, Minister Stephen Lecce framed the outcome as proof that “we’ve done it again” on large infrastructure. A companion summary from Ontario Delivers Darlington Refurbishment Project Ahead of Schedule and Under Budget, shared by Andrea Khanjin, MPP, stresses that the renewed plant will continue to power 3.5 million homes, underscoring how a single site can anchor system reliability.
A made‑in‑Ontario industrial strategy
Beyond the kilowatt‑hours, Darlington has been treated as an industrial project designed to maximize local benefits. OPG reports that the refurbishment is expected to generate about $90 billion in economic benefits to Ontario over its life, with 96 percent of project spending staying in the province. That local focus is echoed in a social media post from Minister Stephen Lecce, where a short video celebrating the work attracted 307 likes and highlighted that 96 per cent of the Darlington refurbishment was #MADEINCANADA. That kind of messaging is not just political branding, it signals a deliberate attempt to build and retain nuclear expertise at home.
Local leaders have been quick to frame the project as a point of civic pride. A statement Municipality of Clarington quotes Clarington Mayor Adrian Foster calling it a “proud moment” and noting that all eyes are on Darlington as a model for large‑scale clean energy construction. A separate municipal release from Municipality of Clarington reinforces that message, tying the station’s success to local jobs and long‑term investment. When a Facebook page titled Moving to Canada proclaims that ONTARIO MAKES GLOBAL, it captures how the project has become a symbol of provincial capability as much as a power plant upgrade.
Global signal: nuclear megaprojects can be delivered
International observers have taken notice of what has been achieved at Darlington. A post from the World Nuclear Association argues that Canada is now leading the world in demonstrating that large nuclear projects can be delivered reliably, describing the refurbishment as a foundation for future builds and praising the industrial capabilities and supply chain strength behind it. That assessment is captured in a Facebook update from the World Nuclear Association, which frames the project as a benchmark for other countries. A similar sentiment appears in a second post from the same organization, which stresses that Canada is now on this front.
Industry‑focused outlets have echoed that framing, describing the work as a Showing the world what is possible when nuclear megaprojects are tightly managed. A technical briefing on Darlington Refurbishment notes that Construction was completed ahead of schedule and under budget, reinforcing the message that cost and schedule discipline are achievable. Another analysis of the Massive Nuclear Reactor Refurbishment in Ontario Completed Ahead of Schedule underlines that the project stayed within its financial envelope even when including interest and escalation, a detail that matters for investors and regulators.
From refurbishment to next‑generation reactors
Darlington’s story does not end with the last refurbished Unit returning to service. The site is also home to The Darlington New Nuclear Project, which aims to build Canada’s first grid‑scale Small Modular Reactor. OPG’s project page explains that the Small Modular Reactor initiative is intended to help meet increasing demand from electrification, with Upcoming milestones that include site preparation and early construction. A separate update on the Darlington New Nuclear underscores that this SMR will be the first of its kind in the country.
Provincial leaders have already linked the refurbishment’s success to confidence in this next phase. A Facebook post from Stephen Lecce notes that Construction on the first of four small modular reactors at a nuclear station east of Toronto is set to begin this year, with the province saying the units are expected to operate for 65 years. A separate summary of the SMR budget explains that The Ontario Energy Board will review how OPG recovers the costs of this project through regulated prices, and that the levelized cost of electricity is expected to be competitive with other low‑carbon options, as outlined in an analysis from Ontario Energy Board and OPG. In effect, the refurbished station is becoming a launchpad for the next generation of nuclear technology.
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*This article was researched with the help of AI, with human editors creating the final content.
