Rail transport is a very energy efficient form of transport with excellent green credentials. Steel-wheels upon steel-rails provides low friction and therefore low rolling resistance, resulting in much reduced energy usage compared to air and road transport. KiwiRail is said to cause 70% less emissions than road transport, even with the majority of their trains operated using diesel locomotives. Rail transport becomes zero emissions when electrified. In addition, modern electric locomotives and passenger rolling stock can recoup energy via regenerative braking technology, recapturing between 10-45% of the original energy used. This recouped energy can be used by other trains or feed back into the national power grid.
