Energy in Ontario

Table 1: Total Ontario energy generation by selected fuels, and related lifecycle pollution emissions, from to 08:00 EDT on Apr 29 2017
FUEL MWh CO2, tons PM, kg NOx, kg SOx, kg
Nuclear 776 14 6 30 18
Gas 139 66 3 86 1
Wind 0 0 0 0 0
TOTAL 915 81 9 116 19
Wind + Gas 139 66 3 86 1
The combination of wind and gas generators produced 139 megawatt-hours (MWh) in the hour ending 08:00, and emitted 66 tons of carbon dioxide (CO2), 3 kg of particulate matter (PM), 86 kg of oxides of nitrogen (NOx), and 1 kg of oxides of sulfur (SOx).

Had a combination of wind and gas replaced the 776 MWh that the nuclear fleet produced, the total environmental impact would have been:
  • 365 tons of CO2
  • 18 kg of PM
  • 474 kg of NOx
  • 10 kg of SOx



Table 2: Total Ontario energy generation by selected fuels, and related lifecycle pollution emissions, from midnight to 08:00 EDT on Apr 29 2017
FUEL MWh CO2, tons PM, kg NOx, kg SOx, kg
Nuclear 9,315 172 75 363 214
Gas 1,251 598 26 776 9
Wind 0 0 0 0 0
TOTAL 10,566 770 101 1,139 223
Wind + Gas 1,251 598 26 776 9
The combination of wind and gas generators produced 1,251 MWh between midnight and 08:00 on Apr 29 2017, and emitted 598 tons of CO2, 26 kg of PM, 776 kg of NOx, and 9 kg of SOx.

Had a combination of wind and gas replaced the 9,315 MWh that the nuclear fleet produced, the total environmental impact would have been:
  • 4,184 tons of CO2
  • 186 kg of PM
  • 4,658 kg of NOx
  • 102 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.