While conventional wisdom states that large vehicles are more energy efficient, this study of the ASEAN nations of Indonesia, Malaysia, Thailand, the Philippines, and Singapore in 1984 suggests the opposite. Jeepneys (based on American army jeeps), microbuses (small buses), helicaks (small motorcycles), and bemos (larger motorcycles), all privately operated, outperform their larger and normally publicly operated counterparts, using less than 40% as much fuel as metros and less than 25% as much fuel as buses. A study in San Juan, Puerto Rico, also shows that capacity on smaller vehicles can be purchased for a lower price; each seat costs is almost three times more on a large bus than on a minibus.

Sources: Gabriel Roth and George G. Wynne. Learning from Abroad: Free Enterprise Urban Transportation. V. Setty Pendakur. Institute of Southeast Asian Studies, Urban Transport in ASEAN.

Source: Gabriel Roth and George G. Wynne. Free Enterprise Urban Transportation.