Public transit

File:publictransit1.jpg

Public transit includes city buses, trams and trains. Compared to private cars, public transit has the potential to prevent traffic congestion, save fuel, and save time for the average rider.

However, public transit done wrong could actually use more fuel per rider - especially in places where buses run mostly empty most of the time.^{[QUANTIFICATION needed]}

Low-density suburbs are particularly hard to service in an energy-efficient way, for this reason. We often end up with a particular conundrum:

Not many people ride the bus, so it's a waste of fuel to send buses often.
But if buses don't come often, then the service is too hard to use, so fewer people ride the bus. No one wants to walk 40 minutes to a bus stop or wait 40 minutes for a bus, for example.

This naturally creates controversy between the folks who want to expand public transit vs the folks who don't.

To help resolve this controversy, I propose a simple thought experiment:

Imagine a typical suburb.
Suppose everyone was fully willing to take public transit instead of driving, if only the public transit was convenient and easy to use. For simplicity sake, let's say that people would take the bus if there was 1 bus passing every 8 minutes during peak hours(...)( peak hours could be defined in any number of ways; also we could assume that people would still use their cars in off-peak or wherever the bus service is lacking ), and if bus lines were spaced out only 400m from each other.
How much fuel per km² would it take to send that many buses?
How does that compare to the status quo of suburban car usage, in fuel per km²?
Also compare to the estimated fuel usage of a "no public transit, but people choose to carpool" scenario.
From this, we can get a clue as to whether public transit could really help the suburbs save fuel or not.

Analysis in progress - someone is working on this research.
Results will be posted here soon ♥

See also