Lifecycle Emissions Benefits
Changing Tailpipe Emissions Standards
Manufacturers must ensure that their vehicles comply with emission standards. Standards may apply to the entire vehicle as is the case for passenger vehicles or to engines which is the current approach for trucks and buses. Emission standards specify maximum levels of air pollutants at the tailpipe. Standards aim to minimize air pollutants such as nitrogen oxide which contributes to the development of urban smog and particulate matter which is harmful to human health. Increasingly stringent emissions standards combined with ongoing vehicle technology improvements have resulted in significant reductions in air pollutants from all types of vehicles.
To date, carbon emissions from vehicles have not been regulated in Canada. This will change as of the 2011 model year when passenger vehicle manufacturers will need to meet specific targets for fleet average carbon emissions on a grams of carbon dioxide per kilometer basis. The new rules will also require that carbon emissions decrease each year until 2016. The expected result is that new model year 2016 vehicles will, on average, emit 25% less carbon than new vehicles sold in Canada in 2008. Canada has also announced that it intends to take a harmonized approach with the United States to regulating carbon greenhouse gas emissions from heavy vehicles.
Lifecycle Emissions Considerations
Tailpipe standards are an important regulatory tool to limit emissions from vehicles. Nonetheless, it is also well understood that there are emissions impacts not just at the vehicle tailpipe, but also from along the entire fuel production and supply chain. These well-to-wheels emissions are emitted to varying degrees for all transportation fuels whether from non-renewable or renewable sources.
With a natural gas vehicle, the carbon benefits arise not just from vehicle operation, but from the fuel lifecycle including production and transportation.
Natural Resources Canada has a model that calculates carbon emissions on a grams per kilometer basis for a wide range of vehicle and fuel pathways. The model was developed over more than a decade and it is based on Dr. Mark Delucchi’s Lifecycle Emissions Model. The GHGenius model includes information on a carbon dioxide equivalent (CO2e) basis for the three major greenhouse gases: carbon dioxide, methane, and nitrous oxide. Air pollutant estimates on a grams per kilometer basis are also included in the model. GHGenius provides information that is useful for comparing the emissions impact of various transportation fuels. The lifecycle emissions concept is an increasingly important one that is starting to be referenced in programs and regulation in Canada. For example, the Province of British Columbia incorporated lifecycle emissions with explicit reference to GHGenius in the development of its Low Carbon Fuel Requirements Regulation in 2009.
Learn more about GHGenius