1. Why are the evaluation years in five-year increments?
The evaluation years were set in five-year increments from 2006 to 2031 to correspond to Census years. In addition, many municipalities have calibrated their demand forecasting models to these years. If a different evaluation year is required from the default choices, users should select the closest year, or produce two scenarios using the adjacent five year increments and interpolate the results.
2. What are the differences between trolley buses, light-rail, subway or metro, and heavy-rail vehicles?
Basic descriptions and examples for these types of system are:
Trolley buses are public transit buses (rubber-tired vehicles) that are connected to a grid network, typically drawing electrical power from an overhead wire. Examples include some buses in service in Vancouver, B.C. and Boston, MA.
Light-rail vehicles run on a rail track, and are typically driven by electric from an overhead wire. Examples of electric light-rail vehicles include Toronto’s streetcar, Calgary’s CTrain, and Los Angeles/Pasadena Gold Line. Although less common, light-rail vehicles can also be diesel-powered such as the O-Train in Ottawa.
Subway/Metro refers to an urban, electric rail transport system that is physically separated from other traffic. Vehicles typically draw electric power from a third-rail. They are usually, though not necessarily, operated underground. Examples include Toronto’s Bloor-Danforth and Yonge-University subway lines, BART system in San Francisco, and Vancouver’s SkyTrain.
Heavy-rail vehicles, for the application of this Tool, include diesel-fuelled commuter rail vehicles. These are commonly referred to as suburban or commuter rail systems, such as GO Transit in Toronto and Metra in Chicago, IL.
The different vehicle types, including buses and fuel technologies, are described in the User Guide.
3. Why do I need to specify a time period – peak hour, daily or annual?
The Tool includes some flexibility in the required inputs recognising that different users may have travel data available for different time periods. Based on their data available, users are allowed to enter vehicle kilometres travelled (VKT) or passenger kilometres travelled (PKT) as tallies for: weekday peak hour, average weekday (daily), or annual.
Users must specify the time period of the VKT or PKT entered in order for the Tool to generate the default expansion factors and expand the input travel data to annual levels.
4. What are expansion factors?
Emissions are more commonly expressed on an annual basis. The Tool was developed to estimate and summarize annual GHG and CAC emissions, and therefore uses annual travel data as inputs.
Expansion factors are used to convert input travel data (VKT or PKT) to annual veh-km or pass-km values:
Annual Travel = XVKT/PKT * (apeak->daily) * (adaily->annual)
where:
XVKT/PKT: VKT or PKT entered as input data
apeak->daily: Peak-hour to Daily Expansion Factor
adaily->annual: Daily to Annual Expansion Factor
Expansion factors are automatically defaulted to 1 based on the entered time period. For example, if the user enters and specifies Daily VKTs, the Tool will automatically set apeak->daily = 1, which the user will not be allowed to modify. The Daily-to-Annual expansion factor may still be modified and should be tailored by the user to reflect travel characteristics in the area of interest.
5. Why do I need expansion factors and how do they affect my outputs?
If annual vehicle or passenger input data is not available, expansion factors are used to estimate annual travel based on peak-hour and daily travel patterns for the area of interest.
The peak-to-daily expansion factor accounts for the fact that travel in the off-peak or non-rush hour periods is lower and therefore the factor is less than 24. An area with a high proportion of "commuter traffic" would have a lower peak to daily factor than an area with traffic patterns that are spread throughout the day. Similarly, an area with significant seasonal travel patterns will have a different daily-to-annual expansion factors than an area with only typical commuting patterns.
Tailoring expansion factors to local conditions will have a very significant impact on the results. Below is a comparison of the annual GHG emissions estimates using a different peak-to-daily expansion factor for Personal Vehicles:
| Input | Scenario 1 | Scenario 2 |
|---|---|---|
| Vehicle kilometres travelled by LDPVs | 100 (veh-km) | 100 (veh-km) |
| Time Period | Peak hour | Peak hour |
| Peak hour->Daily Expansion Factor | 10.5 | 6 |
| Daily->Annual Expansion Factor | 320 | 320 |
| Output | ||
| Annual Travel | 336,000 veh-km | 192,000 veh-km |
| Annual GHG Emissions – Vehicle Upstream | 27.34 t CO2e | 15.62 t CO2e |
| Annual GHG Emissions – Vehicle Operations | 88.48 t CO2e | 50.56 t CO2e |
6. Where did the default expansion factors come from?
All default expansion factors take into account travel characteristics for a large urban area, and are based on the travel characteristics of the Toronto area. Travel characteristics for the Toronto area were based on:
| Input | Default Expansion Factor (Value) | Source / Data based on |
|---|---|---|
| Personal Vehicles | peak-to-daily (10.5) daily-to-annual (320) |
2001 Transportation Tomorrow Survey |
| Commercial Vehicles | peak-to-daily (14) | Ministry of Transportation, Ontario (MTO) 2001 Commercial Vehicle Survey and the University of Toronto Data Management Group cordon count database (also 2001 counts) |
| daily-to-annual (280) | Typical commercial travel patterns | |
| Public Transit | peak-to-daily (6.5) | 2001 Transportation Tomorrow Survey. The default value represents an appropriate expansion factor for buses, light rail, and subways that are used regularly over the course of the day. A lower peak hour to daily expansion factor would be appropriate for commuter rail given that ridership is highly peaked and commute-trip oriented. For commuter rail in the Toronto area (i.e.,GO Transit), the peak hour to daily expansion factor is estimated as 4.5 based on 2001 TTS data. |
| daily-to-annual (300) | Typical transit ridership patterns |
7. What is the difference between Vehicle Upstream and Vehicle Operation annual greenhouse gas (GHG) emissions?
The Tool calculates the GHG emissions from fuel combustion and the upstream fuel cycle effects:
Vehicle Operation emissions are those directly related from the tailpipe of a vehicle (released from the operations of the vehicle).
Vehicle Upstream emissions are created and released from the production of electricity used by electric vehicles as well as from the production, refining and transportation of transportation fuel. This does not include the emissions produced by the manufacturing and end-of-life recycling of vehicles, which are not considered in the Tool.
8. What is the main source of the GHG and CAC emissions factors?
The data used in UTEC are collected from a variety of sources. The GHG and CAC emission factors were drawn primarily from:
GHG emissions for conventional vehicles (i.e. gasoline and diesel): Canada’s Greenhouse Gas Emissions Inventory, published by Environment Canada.
CAC emissions and fuel efficiencies: Outputs from MOBILE6.2C model conducted and published by Environment Canada (National Inventory of CAC emissions).
GHG emissions for alternative-fuel vehicles (i.e. not gasoline and diesel): GHGenius tool developed for Natural Resources Canada.
Additional information for these factors and sources can be found in the UTEC User Guide.
9. Is there a way to easily export the emissions factors or fuel efficiency tables?
At this time, there is no "Export" button to generate a separate file with the data tables.
The Fuel Efficiency, GHG Emission Factors, CAC Emission Factors and the Results output screens are structured so that it can be easily copied and pasted into a spreadsheet program, such as Microsoft Excel.
10. How does the Province/Territory input affect the Tool’s output?
The Province/Territory allows the Tool to account for differing GHG intensities associated with electricity production in each province/territory.
In addition, selecting the Province/Territory provides the provincial breakdowns of light-duty personal vehicles for automobiles and light trucks. The user can choose to use these default values or enter their own.
11. How do I calculate average emissions rates for all of Canada?
At the present time, users must select a particular province for the evaluation. If average rates/results for all of Canada are desired, it would be necessary to run scenarios for each province and weight the results by provincial populations or vehicle registrations. Future versions of the tool will include the option of selecting "All of Canada".
12. Why are other travel modes not available, such as air travel?
UTEC Tool is designed for emission estimates from transportation in an urban environment and does not take into account interregional travel.
13. Are other motorized travel modes, such as motorcycles and school buses, considered in the Tool?
Activity for minor modes is not explicitly included in the Tool. If activity for these modes is known, it could be included under the closest general category.
Motorcycles would fall under Light-Duty Passenger Vehicles (LDPV) and school buses would fall under Medium-Duty Commercial Vehicles (MDCVs).
14. Why are rail vehicle inputs in passenger kilometres travelled, compared to all other inputs in vehicle kilometres travelled?
Inputs for rail vehicles are primarily in passenger kilometres travelled (PKT) because this is a better indicator of rail energy consumption due to the variability of rail vehicle size.