Debunking Myths of Honolulu Rail Transit

The City and County of Honolulu has pursued adding rail transit to the mix of commute options, which currently includes bus, vanpool and ferry in addition to private cars and private bus service. Because of the multi-billion dollar price tag and the 14-year temporary increase to the state's General Excise Tax (GET) to pay for construction costs, the issue has been widely debated. Some ideas have been circulated as (unsubstantiated) facts. These include that: 1) public transportation ridership will increase once the rail system is built, 2) rail consumes less energy than other options, particularly cars, 3) the carbon footprint of the rail system is substantially smaller than that of other transportation options.

After an extensive literature search, review of reported data and checking of reported data against US Census and Department of Energy databases, we have reached several conclusions. In the great majority of cases where US cities have built and maintained light and heavy rail systems, the public transportation systems generally consume about the same amount of energy per passenger mile as private cars. While heavy and light rail transit technology will change little in the next five years, the rising popularity of hybrid, electric and even air-pressure cars will soon make the average car even more energy efficient and further decrease its estimated CO2 output.

We also considered the energy necessary to build a new rail transit system, as is proposed in Honolulu. Looking at the Portland light rail system, we found that the energy used in construction was 172 times greater than the estimated annual energy saved by moving commuters from cars to rail.