Energy in Ontario

Table 1: Total Ontario energy generation by selected fuels, and related lifecycle pollution emissions, from to 13:00 EDT on Jun 27 2017
FUEL MWh CO2, tons PM, kg NOx, kg SOx, kg
Nuclear 773 14 6 30 18
Gas 236 113 5 146 2
Wind 0 0 0 0 0
TOTAL 1,009 127 11 176 19
Wind + Gas 236 113 5 146 2
The combination of wind and gas generators produced 236 megawatt-hours (MWh) in the hour ending 13:00, and emitted 113 tons of carbon dioxide (CO2), 5 kg of particulate matter (PM), 146 kg of oxides of nitrogen (NOx), and 2 kg of oxides of sulfur (SOx).

Had a combination of wind and gas replaced the 773 MWh that the nuclear fleet produced, the total environmental impact would have been:
  • 410 tons of CO2
  • 20 kg of PM
  • 533 kg of NOx
  • 10 kg of SOx



Table 2: Total Ontario energy generation by selected fuels, and related lifecycle pollution emissions, from midnight to 13:00 EDT on Jun 27 2017
FUEL MWh CO2, tons PM, kg NOx, kg SOx, kg
Nuclear 10,856 201 87 423 250
Gas 3,317 1,586 70 2,057 23
Wind 0 0 0 0 0
TOTAL 14,173 1,786 157 2,480 273
Wind + Gas 3,317 1,586 70 2,057 23
The combination of wind and gas generators produced 3,317 MWh between midnight and 13:00 on Jun 27 2017, and emitted 1,586 tons of CO2, 70 kg of PM, 2,057 kg of NOx, and 23 kg of SOx.

Had a combination of wind and gas replaced the 10,856 MWh that the nuclear fleet produced, the total environmental impact would have been:
  • 5,765 tons of CO2
  • 217 kg of PM
  • 5,428 kg of NOx
  • 119 kg of SOx

Definitions

NOx: Nitrogen oxides (NOx) consist of nitric oxide (NO), nitrogen dioxide (NO2) and nitrous oxide (N2O) and are formed when nitrogen (N2) combines with oxygen (O2). NO2 directly affect a human’s health by causing acute bronchitis or pneumonia and by causing a lowered resistance to respiratory infections. Long term exposure can also cause chronic lung impairment. NO2 can also affect both terrestrial and aquatic vegetation.

SOx: SOx refers to all sulphur oxides, the two major ones being sulphur dioxide (SO2) and sulphur trioxide (SO3). The most obvious health effects are irritation and inflammation of body tissues that are contacted by the gas. SO2 can increase the severity of existing respiratory diseases such as asthma, bronchitis and emphysema. It also constricts air passages making it difficult to breathe. SO2 can also harm animals and vegetation. It also corrodes metal, causing building materials and textiles to deteriorate and weaken.

PM: Particulate matter (PM) is a complex mixture of extremely small particles and liquid droplets. PM is made up of a number of components, including acids (such as nitrates and sulfates), organic chemicals, metals, and soil or dust particles. PM can increase susceptibility to respiratory infections and can aggravate existing respiratory diseases such as asthma and chronic bronchitis, as well as heart diseases, in some cases leading to premature death.