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.
Ontario’s grid is
connected to electricity systems in neighbouring provinces and states, allowing
the province to be both an importer and exporter of electricity. Being a part
of a larger North American network is an advantage for electricity customers in
Ontario – it helps maintain the affordability, reliability and sustainability
of Ontario’s electricity system.
The Value of Imports and Exports
Having an electricity grid that is connected to the larger
North American network provides Ontario with access to a number of neighbouring
electricity systems, which enhances operational planning flexibility. These
intertie connections help:
Maintain reliability: If there is an unexpected shortfall due to equipment malfunctions or extreme weather conditions, Ontario can draw on neighbouring electricity generators to supply its energy needs and maintain the stability of its grid.
Drive cost-effectiveness: When electricity is imported or exported, it is being bought or sold. The cost of electricity generated in neighbouring systems is sometimes lower than the cost of electricity generated in Ontario. Being able to import lower-cost electricity helps keep energy bills down for everyone in Ontario.
Make use of surplus electricity generation: At times, Ontario produces more electricity than it needs. This happens most often at night and on weekends when demand for electricity is low, but power plants are still operating. The ability to export to neighbouring grids allows the province to sell surplus electricity that would otherwise be wasted.
Staying Within Our Limits
Ontario maintains grid connections with Manitoba, Quebec, Minnesota, Michigan and New York, actively importing and exporting electricity on a daily basis. The amount of energy intertie transmission lines can transport at one time is limited.
The IESO’s system operators are constantly balancing these limits with Ontario’s energy needs, ensuring we import and export electricity as efficiently and cost-effectively as possible.
