In Ontario, electricity is produced from a number of sources. For a close to real-time supply mix breakdown, please visit the Independent Electricity System Operator website. 

Ontario's system-wide Electricity Supply Mix in 2020
Electricity Sources                         Ontario Electricity Mix
Nuclear Energy 56.8%
Water Power 24.4%
Natural Gas  6.3%   Includes Lennox and dual fuel (natural gas, bioenergy)

Wind

8.7%
Solar PV 2.4%
Bioenergy 0.5%   IESO embedded generation combines biomass and gas

Non-Contracted

0.9%   Variety of fuel types not categorized by IESO