BC Transit Vancouver operating statistics
The following figures are for the 1994/95 fiscal year.
||Average speed including layovers
||22 338 000 km
||53 920 000 kWh
|194 112 GJ
||12 966 285 km
||35 454 170 kWh
|127 635 GJ
||2 105 740
||45 582 954 km
||29 161 885 L
|1 099 694 GJ
||140 948 km
||1 118 718 L
|42 187 GJ
Note that the energy efficiency figures can only be compared between modes
after considering the size of the vehicle and the type of service it performs.
Aside from 21 articulated buses (3% of the fleet), all buses are standard
length. A SkyTrain car is also the same length as a bus, making direct
comparisons between these three modes relatively easy. The SeaBus can seat 400
people, which is approximately 10 to 11 times more than a bus or SkyTrain car.
Thus, only considering size (or, in other words, passenger carrying
capacity), SkyTrain is most efficient, trolleybuses are almost as efficient, and
diesel buses and SeaBus are 2.5 times less efficient, with SeaBus being slightly
less efficient than diesel buses.
However, SkyTrain and SeaBus have a large average distance between stops.
Some diesel bus routes are express routes which have an extremely long distance
without stops, but frequent stops at each end. All trolley bus routes (except
the #10 Hastings Express), however, operate on inner city routes with frequent
stops. Thus, to be fair, trolleybuses should be rated as being better than they
appear in the above chart.
Thus, the overall "fuzzy" judgement is that SkyTrain and
trolleybuses are in the same "ballpark" in terms of efficiency, but
they are more than twice as efficient as the diesel powered buses and SeaBus.
Note: other systems, e.g. Edmonton, report a much larger difference in energy
efficiency between rail and rubber. The "U2" light rail vehicle in use
in Edmonton is 24.28m long (versus a SkyTrain car's 12.7m), yet energy
consumption of a U2 is 10.0 MJ/km, only 15% more than a SkyTrain car, or about
the same as a trolleybus, despite being 90% longer. SkyTrain's relative
inefficiency is likely due to its use of linear induction motors.
- The assumed energy density of diesel fuel is 37.71 MJ/L.
- The distance figure for diesel buses includes service provided by
compressed natural gas (CNG) buses but does not include the energy cost of
those buses. The CNG buses used 59 990 cubic metres of natural gas, or 2234
GJ (at 37.24 MJ per cubic metre) - only 0.2% of the diesel figure. This
difference is negligible.
- Expressed in a more traditional form, the diesel bus fuel efficiency is 64
L/100 km, or approximately 3.7 mpg. The SeaBus fuel efficiency is 794 L/100
km, or approximately 0.30 mpg.
- The average speed of vehicles in service is a more useful measure than the
average speed computed above by dividing distance travelled by service
hours. The average speed in service is not available, but it can be assumed
that it is greater than but close to the average speed shown in the table.
For example, SkyTrain average speed in service is approximately 45 km/h;
each train usually spends a minimum of two minutes waiting at each end of
its 38 minute trip.
- There are, of course, a lot more significant digits shown than are