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Learn about the IESO, Ontario's power system, how the electricity market works and what consumers can do to use electricity more efficiently.

About the IESO

The Independent Electricity System Operator (IESO) works at the heart of Ontario’s electricity system, ensuring that electricity is available where and where it is needed. Here’s how the IESO manages the electricity grid.

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Ontario’s Electricity Grid

Ontario’s demand for electricity varies throughout the day, requiring different forms of supply to perform different roles to meet reliability. Learn how Ontario’s electricity system works.

The Evolving Grid

New technologies are transforming the way we produce and use electricity. The IESO is at the forefront of this change, driving and guiding the electricity sector’s evolution. See how Ontario’s power system is transforming.

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Electricity Pricing Explained

Ontario’s electricity markets drive competition and affordability. Learn more about what influences electricity pricing in Ontario.

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Electricity Facts and Tools

Ontario’s electricity system has many moving parts, all working together to ensure electricity supply remains reliable, affordable and sustainable. Here are some quick facts, videos and online tools to help boost your energy IQ.

Pathways to Decarbonization

While Ontario benefits from one of the cleanest electricity systems in North America, the process of eliminating all emissions from the grid is a significant and complex undertaking. This report explores two scenarios that could see Ontario begin moving toward a decarbonized grid this decade.