Quick answer
Not today, but Ontario needs new supply soon. The IESO expects new energy needs of 8.5 TWh by 2032, rising to 37 TWh and 3,800 MW of new capacity by 2040, as demand grows and contracts expire.1
The forecast
- Electricity demand is forecast to grow 65% by 2050, and up to 92% in a high-demand scenario.1
- New energy needs of 8.5 TWh emerge by 2032.1
- New capacity needs start in 2034 and reach 950 MW in 2035 and 3,800 MW in 2040.1
Why
- Economic and population growth, data centres and electrification of vehicles, heating and industry.1
- Resources reaching the end of their contracts.1
- Nuclear units offline for long refurbishments.23
This was flagged years ago
In 2019 the IESO noted that "a capacity need will arise in 2020" that could grow in 2023 as contracts expired and nuclear reactors went offline.4
The plan
- Demand-side management targeting 900 MW of peak savings from 2025 to 2027.1
- New procurements, including up to 1,000 MW of capacity for 2032–2034.1
- New nuclear, including small modular reactors at Darlington.5
Common follow-up questions
What's the difference between energy and capacity needs?
Energy (TWh) is the total electricity used over time; capacity (MW) is the power available at any moment, especially at peak.
How can homes help?
Using less power at peak times, through efficiency, smart thermostats, batteries and off-peak EV charging, reduces what the grid has to supply.
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Answers are general information as reported by the sources listed on the date shown, not personal financial or technical advice. Programs, prices and rules change. Canadian Energy Standard is an independent company, not affiliated with any government, utility or program named here.
- IESO, 2026 Annual Planning Outlook (March 2026)
- insauga, $26.8 billion nuclear refurbishment to begin in Pickering early next year (August 2026)
- Bruce Power, Life-Extension Program and Major Component Replacement
- Financial Post, OPG's gas-plant purchases partly prompted by shifting nuclear landscape (August 2019)
- Ontario Power Generation, Darlington small modular reactors