Appendices - GSA

Appendix B. Results of Life-Cycle Cost Optimization
(No Tax Incentives)
The key result of the analysis is the size of each renewable-energy measure that
minimizes life-cycle cost at each LPOE. Results indicate that daylighting has
application at LPOE sites without excessive heat loss through skylights and solar
ventilation air preheating is cost-effective at every cold-weather location that can
use the heat. Other measures such as solar water heating depend on the solar
resource and utility rates at a site. PV depends on local incentives to be cost
effective. It is difficult to compare the sizes because they are in different units
(kW, sf, Mbtu/hr, etc.) so in order to compare equal units, the annual energy
delivery of each technology (Mbtu/year) is illustrated in Figure B-2.
Note that each technology is recommended as part of the optimized solution for a
site, and these sizes minimize life-cycle costs. In other words, it is possible for
an LPOE site to cost effectively generate more RE than the optimized solution
indicates, but the life cycle costs would be higher.
Figure B-1: Annual energy delivery of each cost-effectvie RE technology
summed over all GSA LPOE
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