Abstract
In 2010, the GMS Green Freight Initiative (GFI) was launched in the Greater Mekong Subregion (GMS) aimed at reduction of 23% of carbon emissions from long-haul road freight. The additional benefits expected include improving the cost competitiveness and reliability of GMS cross-border road freight after widespread implementation. What has not been considered is the phenomenon of modal shift, where freight from less competitive modes of transport move to those more competitive. In this case, if modal shift occurs from less carbon intensive modes to road, there will be a direct “rebound effect” (the increase in carbon emissions) which would reduce or even cancel out the emission savings occur from greening road freight. In contrast, modal shift to rail would not have a rebound effect and may lead to better carbon reduction potential. To investigate and compare the carbon emission reduction potential of these two parallel developments (GFI and rail) on GMS freight, this study uses a CO2 scenario mode choice model to construct possible future scenarios and estimate their CO2 emissions. The research finds that the GFI will lead to a very significant rebound effect of 125% (in the absence of rail). Modal shift of freight to road transport due to GFI results in an increase of carbon emissions of 42.7 MMT (or 125% of baseline emissions) even though in parallel, emissions savings from greening road freight reduces road CO2 emissions by 23% or 14.7 MMT (43% of baseline emissions). This is significant as greening road freight achieves a large increase in carbon emissions instead of the savings initially intended. This result is surprising especially compared to previous studies where road freight rebound effects were 12-45%. This significant rebound effect in the GMS can be isolated to two factors: the freight routes in the GMS was particularly susceptible to modal shifts to road, and GFI had a relatively low emission savings rate. Estimates show that to cancel out the modal shift rebound effect, GFI needs to lower road freight carbon emissions by at least 67%, a technically challenging accomplishment at this time or in the near future. Rail developments on the other hand, is estimated to contribute 45% carbon emission reductions. Given these estimates, re-evaluation of the suitability of the GMS region for green road freight in its current form is imperative to avoid creating harm to the environment instead of good.