Almost all the electricity Hydro-Québec distributes to its customers is generated from renewable resources which means there are few or no greenhouse gas (GHG) emissions. Hydro-Québec and Environment Canada publish different electricity-associated GHG emission rates because they meet different needs, such as to produce a GHG emissions inventory or to make meaningful comparisons across provinces.

GHG Emissions Inventory

Annual data

The fact sheet entitled Energy Supplies and Air Emissions [pdf 174 KB] lists CO2, SO2 and NOx emissions directly associated with the electricity distributed by Hydro-Québec. It also gives a percentage breakdown of the primary energy sources comprising Québec’s electricity mix (most recent information available).

This fact sheet is helpful to companies wanting to measure their GHG emissions inventory using ISO 14064-1:2006 or the Greenhouse Gas Protocol (GHG Protocol) and required to report electricity consumption GHG emissions. For such companies, electricity emissions are considered indirect emissions (Level 2).

Historical data

The fact sheet entitled CO2 Emissions and Hydro-Québec Electricity [pdf 80 KB] gives CO2 emission rates since 1990.

This fact sheet is helpful for companies wanting to include historical emissions in their GHG reporting.

Important information

  • Both fact sheets concern electricity generated and produced by Hydro-Québec. They do not include electricity for which renewable energy certificates were sold to third parties or electricity from off-grid systems (generated mainly by thermal plants). The CO2 emission rates listed are for generation of electricity only and are thus not based on a life cycle assessment.
  • The fact sheets indicate rates of CO2 emissions, not CO2-equivalent emissions, because only CO2 emissions data are available for certain energy supplies. However, since thermal plant emissions expressed as CO2 equivalents are more than 99% CO2, these emission rates are considered identical.
  • GHG emissions generated by creating reservoirs used to produce electricity are not considered when calculating emissions or Hydro-Québec’s carbon footprint. As indicated in the National Inventory Report : Greenhouse Gas Sources and Sinks in Canada, Environment Canada considers such emissions to be related to a land-use change.
  • Part 3 of the National Inventory Report gives electricity GHG emissions by province and territory. The Québec data cover emissions associated with the production of electricity (Hydro-Québec and independent power producers), including that of off-grid systems (Hydro-Québec). The data do not, therefore, reflect GHG emissions associated with electricity distributed by Hydro-Québec on its main grid. In addition, the data are not based on a life-cycle assessment. For these reasons, it is not recommended that industrial customers use these data to perform life-cycle assessments, calculate their carbon footprint or determine a GHG emissions inventory. They can, however, be used to make comparisons between provinces and territories.

Life cycle

Companies wishing to

  • perform a life-cycle assessment as described in ISO 14040:2006/ISO 14044:2006,
  • calculate the carbon footprint of a product as described in ISO/TS 14067:2013 or
  • issue an environmental declaration for a product as described in ISO 14025:2006

must consider emissions generated in all stages in the life cycle of the product, including those where electricity is consumed. Such emissions are calculated at a rate of 20.72 g CO2 eq/kWh. This rate reflects the life cycle of electricity generated, transmitted and distributed by Hydro-Québec, including purchased and imported electricity. However, it does not reflect the life cycle of electricity from off-grid systems. For more information, consult the report entitled Comparing power generation options and electricity mixes [pdf 7.4 MB].

All environmental indicators associated with the electricity generated, transmitted and distributed by Hydro-Québec are included in the ecoinvent database. These data may be obtained from the International Reference Centre for the Life Cycle of Products, Processes and Services (CIRAIG) at Montréal’s École Polytechnique.