ABSTRACT
Increasing the use of public transport is not enough to make urban transport environmentally sustainable. Trains, buses and trams produce greenhouse gases and other pollutants, even if these are emitted from the power station instead of the tailpipe. Increased patronage only offers environmental benefits when it reduces car travel – provided passengers are carried at sufficiently high occupancy rates. If patronage gains come at the expense of walking or cycling, or because overall travel has risen, then environmental problems are increased, not reduced. Some free travel and park-and-ride schemes have produced increases in ridership while worsening environmental outcomes, as we saw in the previous chapter.
