Quote:
Originally Posted by logan5
That picture is flat out misleading. The passenger load will be spread out evenly across the city.
Let's isolate a driverless car service scenario down to one route, say the 3 Main, which is one of the busiest routes in Metro Vancouver. The driverless cars will only operate along the same route that the 3 Main covers.
During rush hour there are 9 buses operating north bound during the afternoon rush. The peak load for 1 bus during the afternoon rush is 111 boardings per hour, so we calculate how many driverless vehicles it would take to shuttle 111 people in 1 hour. I'm going with 11. That means 10 passengers per hour for 1 driverless car. That's easily doable because there is high turn-over along this route. People getting on dt, then getting off at Skytrain. People getting on at Skytrain will be getting off at Broadway etc.
Then we multiply the number of driverless vehicles by 9 to match the capacity of the buses on this route. That comes to 99 driveless vehicles, vs the 9 buses.
So now we have to fit 99 vehicles over 10 km, but to be fair when we are talking about road space we have to take into consideration how much road space is gained when we take those 9 buses off the road.
An articulated bus (which are run on Main St) is 60 feet long. A sub compact car is 10 feet long, so in the space of 1 articulated bus you can fit 2 driverless vehicles. That leaves a 40 foot distance between the 2 cars. That's plenty during rush hour. The space that buses take on the road is equivalent to 18 driverless vehicles (2 x 9 buses). That leaves 88 cars we have make room for over a 10 km stretch. That averages out to 1 car every 113 meters, or about 1 car every block. There's going to be more demand in the busier areas around the Skytrain station and the B-Line stop, but where buses once dominated the curb lane in the more congested areas, driverless cars could now take advantage of. Once buses are gone, there will be increased capacity in the curb lane.
The bus routes outside of the core of the city are less busy, and once you get out to Surrey there are routes that are far less busy. than the inner city routes. Once the less busy routes are running almost empty most of the day, Translink is going to have to shut them down, and then make some serious decisions on how they run transit city wide.
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The graphic is right on the money. Self-driving or not, a car is still just a car.
You appear to be assuming that those 88 cars will be able to serve all the passengers on the #3, and that they will be the only cars on Main. Rather,
an average load of 30 passengers per bus means
eight cars to replace one bus, not two, and they'll have to share Main with all the other self-driving cars that present-day drivers have now adopted. Right now "only" about 70% of the city gets around by car, or about 1.7 million people - how will the roads look if another 490 thousand people decide to join them?
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