58% as per https://www.ieso.ca//en/Learn/Ontario-Electricity-Grid/Supply-Mix-and-Generation https://www.ieso.ca//en/Learn/Ontario-Electricity-Grid/Suppl... > M

58% as per https://www.ieso.ca//en/Learn/Ontario-Electricity-Grid/Supply-Mix-and-Generation https://www.ieso.ca//en/Learn/Ontario-Electricity-Grid/Suppl... > Most of the electricity produced in Ontario is generated at nuclear and hydro plants... Nuclear: 58% Hydro: 24% Like I said, most of Ontario's power comes from nuclear.