Putting the debate about the causes of Global Warming aside, the issue has at least caused municipalities, as well as public and private entities, to re-think how they might reduce environmental pollution on many levels, and operate more efficiently.
The city of Loma Linda is 70 miles east of Los Angeles, in the Inland Empire — an area with typically well over 300 days of bright sunshine each year. Apparently Thomas Edison's (1847–1931) quote made sense to civic leaders there: "I'd put my money on the sun and solar energy. What a source of power!"
Clear Skies Group, the construction provider for the recent Loma Linda project, is a solar power construction/research and development company based in New York and Los Angeles. Bill O'Connor, project manager for Clear Skies Group, summarized the construction:
"The Loma Linda Civic Center project was a substantial system, comprised of four separate solar systems with 1,572 solar photovoltaic modules (manufactured by Sharp) and four individual inverters to accommodate the modules (manufactured by Satcon).
"The photovoltaic modules had to be mounted on a custom racking system, some of which was self-ballasted and some had to be attached to the roof using stations mounted to the roof deck. There were complicated layout arrangements to minimize shading from existing roof top equipment (AC units, exhaust vents, etc.).
"More challenges: Arrays on separate buildings had to be used to make up the four individual systems, and additional parking structures had to be built to accommodate modules. These four systems had to be tied in to the existing electrical systems of the buildings.
"In order to build the parking structures, over 50 individual footings had to be installed. These were 4 feet in circumference and 10 feet deep. The excavations were made using a 4-foot diameter auger excavator. The scheduling of these excavations was coordinated for minimum obstructions (e.g. large areas of parking had to remain open in order for the town to conduct its business).
"The Town offices remained open and operational during construction. Due to these restrictions there were portions of the work that had to be scheduled during non-business hours, nights and weekends. Scheduling of equipment deliveries was also critical due to the quantities of modules involved. This enabled us to keep the project moving at all times.
"As in all projects of this size, engineering and design was extremely important to the success of the installation — major kudos to the town of Loma Linda and its staff for their cooperation in this project."
California Builder & Engineer questioned Ezra Green, Clear Skies Group CEO, about Loma Linda's use of solar power:
CB&E: If you could briefly summarize four benefits of solar power on a commercial property, what would they be?
- Financial Savings
- Added real estate value
- Environmental benefits
- Strong marketing statement
CB&E: Why did this customer in Loma Linda, Calif., decide to install solar?
Green: The city decided to install solar for several reasons — first, they wanted to help the environment, to set a good example for the city residents and save money for the next several decades. Their annual electric bills were around $350,000 per year, but now the solar system is offsetting 20 percent of the city's costs with an annual savings of $72,000 per year.
While municipalities cannot generally get similar tax credits that are available to commercial establishments, Loma Linda installed the solar system to set a good example and to inspire others to invest in solar energy.
CB&E: Can you give us general costs to purchase and install, and then what would be the typical "pay-back" time to recoup the initial dollars investment?
Green: With an installation cost of $7 per watt, the return on this investment will be 5 years.
CB&E: Sunny Southern California seems a natural fit for solar power. What about parts of Northern California where there are many days of overcast, is solar still a good choice for commercial properties?
Green: Due to the marisne layer, the further north you go in the Pacific Northwest, the lower the benefits will be. The marine layer blocks the sunlight, which reduces the output of the panels, thus your return on investment goes farther out. Also the further north you go, much of the energy produced is from hydro plants, which produce very inexpensive electricity, adding to the length of time it takes to recoup your investment.
CB&E: Do you have other solar installations within California and Hawaii?
Green: In California we have signed a groundbreaking contract in several desert communities which will be benefiting from upwards of 20 megawatts of solar energy. We will be using proprietary mounting systems and installation techniques that will bring the cost of the system down to a minimum.
CB&E: Can you provide any additional details for about the Loma Linda installation?
Green: The project was installed on nine different roofs within the municipal center. The buildings are comprised of the police station, fire station, administration building, carport, and library. The entire system is just shy of 300 kilowatts of energy putting out over 400 kilowatts-hours per year. The savings are in excess of $80,000 per year, not including renewable energy credits.
The project was installed during the summer where the heat was in the 110-degree range and work started at 5 a.m. to beat the high temperatures. Roof temperatures reached 150 degrees and above at mid-day.
The panels were lifted on the roof using telescoping cranes, and the foundations for the carports were dug with 4-foot-wide augers. The entire roof and carport system was designed for earthquake resistance.