Section 490.705 - Use of credits(a) At the request of a fleet or covered person allocated a credit under this subpart, DOE shall, for the model year in which the purchase of a qualifying volume is made, treat that purchase as the acquisition of one alternative fueled vehicle the fleet or covered person is required to acquire under titles III and V of the Energy Policy Act of 1992.(b) Except as provided in paragraph (c) of this section, credits allocated under this subpart may not be used to satisfy more than 50 percent of the alternative fueled vehicle requirements of a fleet or covered person under titles III and V of the Energy Policy Act of 1992.(c) A fleet or covered person that is a biodiesel alternative fuel provider described in section 490.303 of this part may use its credits allocated under this subpart to satisfy all of its alternative fueled vehicle requirements under section 490.302 .(d) A fleet or covered person may not trade or bank biodiesel fuel credits.64 FR 27174, May 19, 1999, as amended at 66 FR 2210 , Jan. 11, 2001