While there has been considerable research focusing on energy efficiency and fuel substitution options for LDVs, much less attention has been given to non-LDV modes, even though they constitute close to half of the energy used in the transportation sector. We conducted an extensive literature review of the non-LDV modes, and in this report we bring together the salient findings concerning future energy efficiency options in the time period up to 2050. The studies reviewed provided potential energy savings for individual technologies within each mode, as well as an overall energy savings representing the case where all possible improvements are implemented.
