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Ontario’s Electricity Production

Where does Ontario’s electricity come from?

If you visit the Independent Electricity System Operator’s (IESO) website, you can find out the Ontario’s electricity grid contributors by type, on a day to day basis. Nuclear power plants supply over 50% of our electricity within the province, at all times. This is OEP_2014because nuclear power output does not vary easily, and therefore supplies Ontario’s steady electricity base-load. As shown in the graph, nuclear power plants produced over 60% of Ontario’s electricity production alone in 2014.

Hydro-electric power is the 2nd largest, but only produces around 20-25%. Natural gas (and oil) fired plants produce another ~10%. These two generator types are relied on heavily to supply the grid during peak demand periods throughout Ontario. They meet Ontario’s peak demands by controlling the turbines and reserving energy. Energy is not only stored via fuel, but also within water reserves.

Wind makes up the majority of renewables in both capacity and production. Unfortunately, Ontario still has a lot to make up for in terms of renewable and sustainable electricity production. The first step remains to be conservation.

The solar electricity production within the renewables category accounts for grid-connected generation only, and does not account for the production of off-grid systems. However, almost all solar generation in Ontario is connected to the distribution system.

Article Submitted by:
Mike Potter,  C. Tech. | Energy Auditor
Efficiency Engineering Inc.