41 C.F.R. § 302-9.4
To reduce the Government's overall relocation costs by allowing transportation of a POV to your official station within CONUS when it is advantageous and cost effective to the Government, and to improve our overall effectiveness if you are transferred or otherwise reassigned to a post of duty at which it is in the interest of the Government for you to have use of a POV for personal transportation. For example, your agency may determine that it is both advantageous and cost effective to the Government to allow for transportation of an alternative fuel POV which would be impractical to drive a long distance to the new official station due to vehicle range capability and fueling availability limitations, but has practical use once at the new official station.
41 C.F.R. §302-9.4