Moore’s Law for buses: Squeezing more Fuel Economy..slowly

by | Traveling

(from HW, Spedsta Team Member in San Diego)

I was recently on the road recently in San Diego and saw a bright, flashy new bus on the road. It turned out to be a “Van Hool TD925”  which was an 81 passenger charter bus designed by the Van Hool company in Belgium. The image below is the bus that I saw, but what it said on the sides of the bus intrigued me “81 Fewer Cars on the Road! ”.


Moore’s law is a popular description of how electronics are getting smaller and cheaper at an incredible pace. Essentially every 18 months, electronic device density doubles or is 2 times the performance. How does fuel efficiency compare in bus technology compare over the years? What is the Moore’s law for bus fuel efficiency? Lets take a look at the numbers.

Historically fuel economy in buses and public transportation have been reported in passenger-miles-per-gallon. Lets take  a look at the ratings of the workhorse bus of  the Greyhound Bus company and the newest Van Tool bus.

  1. MCI 102DL3 Bus: This was first introduced in 1992 and is built by the MCI Company. Greyhound started to use this bus in 1998.  Stated rating is 330 passenger-miles-per-gallon .
  2. Van Hool TD925: First introduced in 2011. Stated fuel economy is 486 passenger-miles-per-gallon.

Just taking those facts, in 13 years fuel efficiency had increased from 330 to 486 passenger-miles-per gallon.  So (on average), there is 12 passenger-mile-per-gallon improvement every year. To keep pace with Moore’s doubling law,  to double fuel efficiency from 330 to 660, it will take 27 years.

To get these numbers in context: electronics performance improvements are happening 18 times faster than improvements in bus performance.  That is the difference between a cheetah running at full speed and a turtle!  Maybe there can be a better way to improve the efficiency of people transportation faster than the walking speed of a turtle.

Follow Us