Old report, but seems to me that barge shipping is more energy efficient than truck or rail (see page x): http://www.cbo.gov/sites/default/files/cbofiles/ftpdoc

Old report, but seems to me that barge shipping is more energy efficient than truck or rail (see page x): http://www.cbo.gov/sites/default/files/cbofiles/ftpdocs/53xx/doc5330/doc02b-entire.pdf http://www.cbo.gov/sites/default/files/cbofiles/ftpdocs/53xx... More recent report from Europe comparing different transport modes for CO2 by kg-km traveled. Shipping is reported as most efficient over rail and road. http://www.eea.europa.eu/data-and-maps/indicators/energy-efficiency-and-specific-co2-emissions/energy-efficiency-and-specific-co2-3#toc-1 http://www.eea.europa.eu/data-and-maps/indicators/energy-eff...