Savvy Solar Thermal System Completed at Two Fully Operational Jails
Best Specialty Contracting Project: MCFM Solar Thermal Installations CMAR (ARRA), Phoenix
Integrating solar thermal systems with gas heating systems at two detention facilities—while both jails remained fully operational—was a sophisticated yet simple project designed with few moving parts for easy maintenance.
A substantial amount of the daily hot water requirements for the two facilities—housing approximately 4,000 inmates—is provided by the system's 316 solar heat collectors, saving an estimated $55,000 annually. It will also reduce CO2 emissions by almost half a million pounds per year.
The closed-loop system, designed to utilize standard plumbing techniques, incorporates variable speed pumps to regulate energy flows. The result: a reduction of electrical power consumption by more than half. Any extra cost of such controls will pay back within one year, a crucial factor in any public building project. The closed loop system also prolongs the life of machinery and optimizes energy transfer.
Control equipment was placed indoors to avoid wear and tear from Arizona's sun, allowing employees who currently manage the energy systems to operate the water heating system, further increasing the system's utility.
Initial measurements show more heat transfer than budgeted, impressive for a system expected to be in use for at least 25 years.
Submitted by: Builders Guild Inc.
Owner: Maricopa County-Facilities Mgmt. Dept., Phoenix
Contractor: Builders Guild Inc., Mesa, Ariz.
Lead Design: Michael Baker Corp., Phoenix
Structural Engineer: Landa & Associates, Phoenix
MEP Engineer: Walsh Engineering, Tempe, Ariz.
Solar Consultant: Greenfield Dynamics, Tempe, Ariz.