Marginal Greenhouse Gas Emissions of Ontario’s Electricity System and The Implications of Electric Vehicle Charging

To reduce emissions from the transportation sector, electric vehicles (EVs) are promoted in many regions around the world. However, it is important to account for greenhouse gas (GHG) emissions from electricity generation while assessing their emission reduction ability. This study developed a two-step approach to estimate GHG emission reductions from introducing EVs in the Greater Toronto and Hamilton Area (GTHA). With electricity generation data for 2011 and 2017, hourly marginal emission factors were calculated using a multiple linear regression model that considers load and temporal variations. Based on a comprehensive travel survey, a travel demand model was used to estimate hourly energy consumption of EV charging with five charging scenarios (i.e., home charging, work and shopping charging, night charging, downtown vs. suburb charging, and an optimal low emission charging scenario) and two EV penetration rates (i.e., 5% and 30%). The authors observed that vehicle electrification could deliver substantial use-phase GHG savings in the GTHA. Compared with an equivalent set of conventional gasoline vehicles, EVs have 85% lower fuel cycle GHG emissions when using the 2017 marginal electricity generation mix. At 5% EV penetration rate, night charging has the second lowest emissions, nearly matching the low emission charging scenario. At 30% EV penetration, the low emission charging achieves by far the highest reduction (i.e., about 96%), suggesting a need for policies that will smooth out charging demand between 1 am and 7 am to minimize GHG emissions associated with EVs in the GTHA.

  • Supplemental Notes:
    • This paper was sponsored by TRB committee ADC70 Standing Committee on Transportation Energy.
  • Corporate Authors:

    Transportation Research Board

  • Authors:
    • Gai, Yijun
    • Wang, An
    • Pereira, Lucas
    • Hatzopoulou, Marianne
    • Posen, I Daniel
  • Conference:
  • Date: 2019


  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; References; Tables;
  • Pagination: 10p

Subject/Index Terms

Filing Info

  • Accession Number: 01698019
  • Record Type: Publication
  • Report/Paper Numbers: 19-05091
  • Files: TRIS, TRB, ATRI
  • Created Date: Mar 1 2019 3:51PM