Due to the increasing threat of the environmental impact of vehicle emissions, actions need to be taken against them. As a response, Electric Vehicles (EV) and Plug-in Hybrid Electric Vehicles (PHEVs) are introduced to the market with the purpose of mitigating the quantity of pollutions emitted by fuel consumption. This paper shows that with the increasing adoption of EVs and PHEVs, emissions decrease significantly through 2012 - 2050, specifically in three zones which are The Metropolitan Area of Toronto, Hamilton, and Ottawa Ontario. This is presented by assuming three different scenarios considering different rate of EVs and PHEVs penetration. The number of related EVs and PHEVs through each scenario is forecasted. To show the quantity of emissions produced in the zones considering the scenarios, the emissions factor for Greenhouse Gases pollutants are found. In the next step, the total commuting distances of vehicles in each scenario are found and when combined with the emissions factors, the total emissions produced in each scenario are presented. The main contribution of this paper confirms that by adopting modern vehicles in three main zones of Ontario, Canada, the total emissions could decrease by almost 40% to 50%, which would be very significant amount.