Public Transport Systems Not Always A Greener Solution
Posted on: Monday, 8 June 2009, 10:05 CDT
A new study from researchers at the University of California at Davis has found some evidence that dispels conventional wisdom about green transport.While most environmentally conscious people would be quick to assume that urban public transport systems are safer in regards to carbon emissions, environmental engineers Mikhail Chester and Arpad Horvath found that in some cases, people would be better off traveling through town in a gas-guzzling, high emission SUV.
Chester and Horvath told AFP that there are many factors that rarely go into public consideration.
"We are encouraging people to look at not the average ranking of modes, because there is a different basket of configurations that determine the outcome," said Chester.
"There's no overall solution that's the same all the time."
Researchers noted that the overall efficiency of a mode of public transport often depends on the location . For example, the metro system in Boston has high energy efficiency, but 82 percent of its energy comes from fossil fuels.
In contrast, San Francisco’s rail system is less energy-efficient than Boston’s system, but it is more economically friendly because just 49 percent of its energy is derived from fossil fuels.
Their report shows how “tailpipe” estimates fail to add emissions involved in building transport infrastructure. These overlooked figures add 63 percent to the "tailpipe" emissions of a car, 31 percent to those of a plane, and 55 percent to those of a train, said Chester and Horvath.
Additionally, researchers said that another key factor is seat occupancy.
In some cases a SUV that is fully occupied may be more efficient than a public train that is only a quarter full, they said.
"Government policy has historically relied on energy and emission analysis of automobiles, buses, trains and aircraft at their tailpipe, ignoring vehicle production and maintenance, infrastructure provision and fuel production requirements to support these modes," researchers found.
The report is published in Environmental Research Letters, a publication of Britain's Institute of Physics.
-------------
On The Net:
UC Davis
Britain's Institute of Physics
Source: redOrbit staff
Related Articles
- Steve Williams Named Chairman of American Transportation Research Institute
- Energy Conversion Devices and Mercury Solar Systems Sign Multi-Year Supply Agreement for Photovoltaic Laminates
- Researchers Disrupt System Involved In Cancer, Degenerative Disease
- Smart Energy Solutions Launches New Intelligent Switching System for Power Transmission Industry
- GE Digital Energy Showcases Its Innovative HardFiber(TM) System at Leading Global Conference on Electric Power Systems
- Stellar Energy Installs 121 kW SolarSave(R) Membrane System on San Francisco Public Utilities Commission Facility
- Titan Energy Worldwide, Inc. Delivers Emergency Power System to St. Paul Administration and Education Center
- Scientists at Center Stage: New Focus on Alternative Energy Shines Spotlight on Researchers
- National Stem Cell Announces Publication of Sponsored Research Findings for Type I Diabetes
- Alliant Energy Completes Sale of All Pipeline Systems
User Comments (0)


RSS Feeds