19 medium-security prison for males. It opened 4923 MBtu per year of energy for domestic nology, the primary economic factors will in 1985 and was designed for about 500 water heating, displacing electric water be the cost of the system and the cost of inmates but is currently housing about 1200. heating. (The electricity saved is about the conventional energy.
Facilities dependent on With five two-story housing units and a amount 150 people would use for all pur- high-cost water heating are definitely more kitchen/laundry building, the facility poses.) Because electric power plants only likely to find parabolic-trough solar water- uses an average of about 21,000 gallons convert about one-third of fossil-fuel heating systems economically attractive. (79,494 liters) of hot water per day for energy to electricity, and electric water The technology for domestic water kitchen, shower, laundry, and sanitation heaters are about 95% efficient, the fossil- heating with parabolic-trough collectors needs.
The facility now uses electricity for fuel combustion saved will be about was advanced considerably by higher- all of its hot-water heating (current cost 15 billion Btu per year. As indicated in temperature systems built in the 1980s for 6.2¢/kWh) and other utility needs. It does Appendix G, the 28 million kWh saved over steam electric generation. Although the not have access to natural gas and propane the life of the project will eliminate more company that built those systems is no was considered a safety concern in the than 80,000 kilograms of nitrogen oxides longer in business, the systems are all still prison setting.
and nearly 100,000 kilograms of sulfur operating, demonstrating the technology’s IST has an ESPC contract, which was dioxide pollution plus 27 million kilograms technical merits and durability of the tech- negotiated prior to the new IDIQ, to build of carbon dioxide greenhouse gas emissions. nology. Only one company, IST, is currently and install a parabolic-trough solar water- Life-cycle cost analysis for the FCI- manufacturing parabolic-trough collectors heating system for FCI-Phoenix.
The Phoenix project is shown in Appendix G, for solar water-heating systems, but that designed system includes 18,000 square feet and cash-flow analysis for the facility and company has an excellent track record, hav- (1672 square meters) of parabolic-trough for the investors is shown in Appendix H. ing built several effective systems—all at solar collectors to be located inside a fenced The project has excellent economics, with government facilities and all operating quite enclosure of about 1.2 acres (0.5 hectare). A life-cycle energy savings nearly twice the well.
21,000-gallon (79,494-liter) thermal energy cost of the project and an 8-year simple pay- Just as importantly from a Federal-facil- storage tank will be located adjacent to the back. These figures reflect the favorable ity perspective, IST has an IDIQ contract solar field. This larger-than-typical storage impacts of a good solar resource and a large with FEMP for installing parabolic-trough will allow the system to meet a projected facility, but also show how high conven- water-heating systems at any Federal facility 82% of the facility’s hot-water needs and tional energy costs make a parabolic-trough where a system would be appropriate.
The also meet most of the morning peak demand system economically attractive. The utility near future of parabolic-trough water heat- at FCI-Phoenix—which will reduce charges in this case does not have a peak pricing ing will be as much a reflection of the from the utility. An incoming cold-water system per se, but the case does show how attractiveness of ESPC financing as of the supply line is routed to a copper-coil heat time-of-day or highest-demand pricing sys- technology itself. The IDIQ greatly facili- exchanger in the thermal storage tank and tems can make renewable energy systems tates the procurement process.
Once the then through insulated underground piping more attractive—particularly systems that system is in place, there is essentially no to seven buildings. The solar-heated water is meet more of the demand. burden on the facility. The energy service tempered down to 140˚F (60˚C) when nec- Construction of the parabolic-trough company conducts all operation and mainte- essary and then serves as preheated incom- project for FCI-Phoenix will begin in early nance and facility staff need not do anything ing water for the existing electric water 1998, so lessons learned for the facility are extra. ESPC requires no funding from the heaters in each building. limited so far.
Even though ESPC was used facility and guarantees the facility savings. The system will include 120 parabolic- on this project, finalizing the contract and Virtually the only risk to the facility would trough collectors built by IST. Each 150- commencing installation took longer than be the inconvenience of removing the square-foot (14-square-meter) collector anticipated. This suggests the importance of parabolic-trough system should it not work (20 feet by 7.5 feet [6.1 meters by 2.3 meters]) lining up investors ahead of time and being adequately.
ESPC financing also enables will have an aluminized acrylic reflective aware of the regulations involved in dealing the energy service company or third-party surface mounted on a steel trough. The sys- with Federal agencies and in setting up investor to exploit tax credits and acceler- tem is modular and the enclosure will have business in a new state. ated depreciation—and pass on benefits to excess space, so the system can be easily the facility—that would not be available expanded. The system will be controlled by The Technology in to a facility purchasing a system.
one Honeywell Fluxline master start-up and The FEMP Federal Renewables Pro- Perspective field controller and four Honeywell local gram at the National Renewable Energy sun-tracking controllers. Four three-phase Laboratory can quickly assess whether solar Parabolic-trough solar water heating is electric motors with jack/cable drive will water heating is likely to be economically a proven technology that can play a signifi- actually turn the collectors. Water will be attractive for a Federal facility with a mini- cant role in reducing conventional energy delivered to and from the collectors in insu- mum of information.
The potential for use at Federal facilities in the Southwest or lated two-layer, flexible stainless-steel application at rural Federal facilities in the other areas with high direct-beam solar radi- hoses. IST will fabricate the nonpressurized Southwest, which are more likely to have ation. Facilities such as prisons, hospitals, stainless-steel thermal energy storage tank. high energy costs and a high solar resource, and military barracks with large, constant The parabolic-trough collector system is quite good. water use loads are particularly good candi- for FCI-Phoenix is designed to provide dates. As with any alternative energy tech-