Energy in Ontario

Table 1: Total Ontario energy generation by selected fuels, and related lifecycle pollution emissions, from midnight to 00:00 on Oct 23 2017
FUEL MWh CO2, tons PM, kg NOx, kg SOx, kg
Nuclear 10,053 186 80 392 231
Gas 179 86 4 111 1
Wind 962 7 11 20 18
TOTAL 11,194 279 95 523 250
Wind + Gas 1,141 93 14 131 19
The combination of wind and gas generators produced 1,141 megawatt-hours (MWh) in the hour ending 00:00, and emitted 93 tons of carbon dioxide (CO2), 14 kg of particulate matter (PM), 131 kg of oxides of nitrogen (NOx), and 19 kg of oxides of sulfur (SOx).

Had a combination of wind and gas replaced the 10,053 MWh that the nuclear fleet produced, the total environmental impact would have been:
  • 3,963 tons of CO2
  • 215 kg of PM
  • 5,157 kg of NOx
  • 130 kg of SOx



The combination of wind and gas generators produced 1,141 MWh between midnight and 00:00 on Oct 15 2017, and emitted 93 tons of CO2, 14 kg of PM, 131 kg of NOx, and 19 kg of SOx.

Had a combination of wind and gas replaced the MWh that the nuclear fleet produced, the total environmental impact would have been:
  • tons of CO2
  • 201 kg of PM
  • 5,027 kg of NOx
  • 111 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.