Darlington New Nuclear Project: A Significant Investment in Ontario's Future Energy Supply
The Darlington New Nuclear Project (DNNP) represents a significant investment in Ontario’s future energy supply. Located at the existing Darlington Nuclear Generating Station, the project aims to deliver clean, dependable, and affordable electricity, not only for Ontario but potentially for wider distribution. The core of the initiative involves deploying four BWRX-300 Small Modular Reactors (SMRs), a cutting-edge Generation IV reactor design supplied by GE Hitachi Nuclear Energy (GEH). Ontario Power Generation (OPG) is spearheading the project, holding the necessary licenses and responsible for operations.
A collaborative network of key players is crucial to the DNNP’s success. Beyond OPG and GEH, SNC-Lavalin serves as the project's Architect-Engineer, while Aecon leads the construction efforts. A specialized Tunnel Boring Machine, dubbed "Harriett Brooks," from Germany, is slated for arrival and assembly in 2026. The Tennessee Valley Authority (TVA) is partnering on similar BWRX-300 projects in the United States, with companies like Bechtel and Sargent & Lundy also contributing to TVA’s Clinch River SMR project.
The total investment for the Darlington New Nuclear Project is substantial, budgeted at C$20.9 billion, encompassing site preparation, engineering, design, and the construction of all four reactors. The first BWRX-300 reactor is projected to cost C$7.7 billion, with C$6.1 billion dedicated to the reactor itself and C$1.6 billion for common systems and services. Project planners anticipate cost reductions for subsequent reactors due to improved efficiencies. To manage costs and protect ratepayers, OPG is exploring various financial instruments and pursuing potential equity partnerships with First Nations communities. The construction phase alone is expected to inject over C$500 million into Ontario’s economy.
Milestones for the project include the arrival of the "Harriett Brooks" Tunnel Boring Machine in Germany (2026) and the delivery of the generator rotor to the site by summer 2027. The TVA has already submitted the initial portion of its construction permit application to the U.S. Nuclear Regulatory Commission in April 2025. While the complete construction timeline remains undefined, it is projected to span several years.
The economic and social benefits of the DNNP are considerable. The project is anticipated to create approximately 3,700 jobs annually over 65 years and contribute an estimated C$38.5 billion to Canada’s GDP during that same period. Furthermore, roughly 80% of project spending is expected to remain within Ontario, boosting local businesses and creating a ripple effect throughout the province’s economy. A key focus is also placed on fostering equitable partnerships with First Nations communities.
To ensure project efficiency and minimize potential risks, the Darlington New Nuclear Project is employing an Integrated Project Delivery (IPD) framework, uniting the expertise of OPG, GEH, SNC-Lavalin, and Aecon. This collaborative approach is designed to streamline decision-making and prevent cost and schedule overruns.
