10 C.F.R. § 436.37 – Annual energy audits.

(a) After contractor implementation of energy conservation measures and annually thereafter during the contract term, an annual energy audit shall be conducted by the Federal agency or the contractor as determined by the contract. The annual energy audit shall verify the achievement of annual energy cost savings performance guarantees provided by the contractor.
(b) The energy baseline is subject to adjustment due to changes beyond the contractor's control, such as—
1. (1) Physical changes to building;
2. (2) Hours of use or occupancy;
3. (3) Area of conditioned space;
4. (4) Addition or removal of energy consuming equipment or systems;
5. (5) Energy consuming equipment operating conditions;
6. (6) Weather (i.e., cooling and heating degree days); and
7. (7) Utility rates.
(c) In the solicitation or in the contract, Federal agencies shall specify requirements for annual energy audits, the energy baseline, and baseline adjustment procedures.