While Ontario has made strides in power generation from multiple sources and successfully phased out coal, power transmission remains a weakness, not just within but between provinces. Additionally, aggressive growth targets for housing will require upgrades in generation and delivery.

Ontario’s plan to build an additional 1.5 million homes will require substantial upgrades in power generation and delivery. Areas like downtown cores will require substantial upgrades before they can support a large amount of intensification, and the Government of Ontario must be prepared to make this investment if housing targets are to be met.

Ontario currently has 30,000 km of transmission lines and 260,000 km of distribution lines. To meet the target of 1.5 million new homes, it’s reasonable to assume an additional 8,600 km of high-voltage circuits (230 kV/500 kV) and 74,000 km of feeders and service drops would be required, as well as an extra 14.3 TWh of energy per year (a 9% increase) and an additional 3 GW of peak capacity – roughly equivalent to 3 new nuclear reactors or 4-5 gas plants.

The GNCC calls for critical transmission lines to be included in the Government of Ontario’s infrastructure package to support housing development, reflecting our view that power-grid capacity is a foundational element of any strategy to accelerate housing supply.

2023-ongoing