In establishing a new requirement for electric equipment referred to in subsection (b) and in procuring electric equipment referred to in that subsection, the Secretary of a military department or the head of a Defense Agency, as the case may be, shall provide a preference for the procurement of the most energy efficient electric equipment available that meets the requirement or the need for the procurement, if providing such a preference is consistent with the energy performance goals and energy performance plan for the Department of Defense developed under section 2911 of this title and supported by the special considerations specified in subsection (e) of such section.