Life cycle costs are the sum of the present values of—

(a) Investment costs, less salvage values at the end of the study period;

(b) Non-fuel operation and maintenance costs:

(c) Replacement costs less salvage costs of replaced building systems; and

(d) Energy and/or water costs.

[55 FR 48220, Nov. 20, 1990, as amended at 61 FR 32651, June 25, 1996]