Engineering Inc. - November/December 2010 - (Page 24)

Powered by the Sun Workers install solar arrays on a parking canopy at a military base in Southern California. MULTI-PROJECT FEATURE PROJECT: Canopy-Mounted Solar Panels at Three Military bases, California FIRM: W burns Engineering, Inc., Philadelphia hen the Naval Facilities Engineering Command (NAVFAC) Southwest decided to install solar panels over vehicle canopies at three bases in California, its goal was to improve energy efficiency while making use of funds available through the American Recovery and Reinvestment Act for renewable infrastructure projects. With construction completed in June, NAVFAC tapped Philadelphia-based Burns Engineering, Inc., to design the electrical, civil, structural and mechanical systems for three solar photovoltaic (PV) arrays. “To efficiently harvest the sun’s energy, 24 ENGINEERING INC. the design calls for 3-feet by 5-feet solar panels assembled into large arrays of up to 2,200 panels and mounted on the parking areas’ canopy roofs,” explains John E. Burns, the firm’s senior vice president. The panels are connected to an inverter that converts singlephase DC power to three-phase AC power, which is then used to offset purchased power from the local grid or to supply power to the grid when facility demand load is less than solar power production. The firm provided a range of design services for the project, including the PV, electrical distribution and inverter systems; site configuration; the parking canopy structures, working with the steel manufacturer; and ventilation systems for the equipment rooms. The solar arrays at two of the bases—Marine Corps Air Station Miramar in San Diego and Naval Weapons Station Seal Beach—are capable of producing 200 kW of power, while the array at Marine Air Ground Task Force Training Command Marine Corps Air Ground Combat Center in Twentynine Palms, Calif., generates 500 kW of solar power. “These facilities are now able to reduce their carbon footprints, reduce their dependency on the electrical grid for power and reduce their annual electrical costs in line with the project’s goals,” says Burns. Burns’ engineers faced several challenges, including optimizing the canopy structures’ orientations and tilts for maximum power generation while balancing cost and aesthetic appearance; matching the temperature characteristics of solar PV panels to the local climate and inverter characteristics; developing a revenue-grade John E. Burns metering system; connecting the PV generating system to the utility grid in accordance with state and local rules and regulations; and selecting material and equipment to ensure ease of maintenance and reduction of mean time to failure. “We provided NAVFAC with a system that would generate a minimum of kW generation over 20 years by choosing the correct materials and by balancing the generation potential of every panel with its orientation,” Burns says. n NOvEMbER / DECEMbER 2010

Table of Contents for the Digital Edition of Engineering Inc. - November/December 2010

Engineering Inc. - November/December 2010
Contents
From ACEC to You
News and Notes
Market Watch
Legislative Action
Power Play
2010 Fall Conference Highlights
Ins and Outs
Re-energized
Business Insights
Young Professionals of the Year
Members in the News

Engineering Inc. - November/December 2010