48 CFR §217.174

1. (a)The head of the contracting activity may enter into a contract for a period not to exceed 10 years for the purchase of electricity from sources of renewable energy, as that term is defined in section 203(b)(2) of the Energy Policy Act of 2005 (42 U.S.C. 15852(b)(2)).
2. (b)Limitations. The head of the contracting activity may exercise the authority in paragraph (a) of this section to enter into a contract for a period in excess of 5 years only if the head of the contracting activity determines, on the basis of a business case analysis (see PGI 217.174 for a business case analysis template and guidance) prepared by the requiring activity, that—
   1. (1)The proposed purchase of electricity under such contract is cost effective; and
   2. (2)It would not be possible to purchase electricity from the source in an economical manner without the use of a contract for a period in excess of 5 years.
3. (c)Nothing in this section shall be construed to preclude the DoD from using other multiyear contracting authority of DoD to purchase renewable energy.