A reader writes:
Eric A. Morris states that "only" ten people on a bus is no better than "1.6" people in a car, ignoring that the grouping of people on buses alleviates the need for 10 vehicles on the road, thus making roads less congested, opens up more parking opportunities for those who do drive, and allows people without cars more flexibility in their travel plans throughout the day (not to mention freeing their income from having to purchase and expensively maintain an auto).
Another writes:
Morris completely forgot to consider utilization. A bus or subway car spends practically every day for about 19 hours per day on the road or rail. It's perfectly ordinary for 1980s vintage (or older) subway cars to be moving people in 2012. A private car, in contrast, spends the vast majority of its much shorter life sitting in a garage, driveway, or parking lot – all of which require vast amounts of energy to build and almost none of which is cleanly produced and transmitted over a grid.
Another:
The real energy advantage of transit is that it enables the higher densities in which many trips need not involve a motorized vehicle at all, and it is these trips on foot or bicycle that really are green.
The downtown worker probably walks to lunch and the ATM while the equivalent suburban office-park worker would need to drive to the next strip mall over. The argument that we've already put transit in the places where it is efficient makes the same mistake that justifies highway expansions: that there is a fixed demand for transportation between any two points, independent of the existing capacity. But just as new roads create new traffic through the well-documented phenomenon of induced travel, transit infrastructure can create its own demand as well.
Perhaps the best-known example is the Rosslyn-Ballston Metro corridor in Arlington, VA, which today provides thousands with transit-and-walking centric living, working, and shopping, but which nobody would have classified as "low-hanging fruit" when 40 years ago when construction started. Likewise, the most energy efficient light rail system (Figure 2.2 of the cited Transportation Energy Data Book) in San Diego, is also the oldest, meaning it has had the most time to reap the energy benefits of its influence on development and lifestyle patterns.
A certified transit expert writes:
Not only do I agree that we are overselling (conventional) mass transit, Eric Morris is also overselling it by claiming that the average bus has an average of about 10 passengers. This is a gross over estimate if computed properly. If one takes the total passenger miles traveled on buses in the US and divides it by total bus miles, then the number comes out to actually be less than 5.
Buses have a significant number of passengers on only a portion of any route in the prime of two directions during the few "peak hours" of any day. The rest of the time and in the off-prime direction all the time, their ridership is very low, leading to the very poor average number of passengers. The fact that buses operate on a fixed schedule along a fixed linear route with relatively little coordination between routes restricts them from adequately serving the needs of the traveling public that wishes to go between a wide variety of locations throughout most of each day, not just the peak hours. This diffusivity of the fundamental demand for mobility is simply not adequately served by conventional mass transit systems.
This is not true for a class of new transit systems known as Automated Transit Networks (ATN). These systems (precursors of which exist in Morgantown WV, Heathrow Airport, UK and Masdar City, UAE) are small automated vehicles operating demand-responsively between any pair of stations interconnected by a network of narrow exclusive roadways. Provided is elevator-like service. A vehicle is usually waiting for a customer and encouraged is the sharing of rides during times when there is some likelihood that some additional customers may desire similar mobility at about the same time as the initial rider. As with elevators, doors are left open for a short while, say one minute, to accommodate anyone else. Individual vehicles need not be large, essentially that of a normal elevator, because it is very rare that large groups of people want to travel between the same stations at about the same time. In such rare events, a group of vehicles can be used.
More importantly, during most of the time when it is rare to have more than one person wanting to travel, these systems provide equally high-quality, elevator-like on-demand service. Provided is 24×7 mobility that is an attractive alternative to the personal automobile for large portions of tomorrow's cities.
The Dish 