Utilities are often school districts’ second greatest expense after staff. Between budget cuts and rising energy prices, many U.S. schools have found themselves struggling. California’s San Ramon Valley Unified School District (SRVUSD) near Oakland, Calif., found itself in such a situation and knew something had to be done.
After several months of studies and public meetings, the SRVUSD board of education opted to take advantage of a government bond program. In May 2010, the district approved a solar project to generate ongoing savings that would enable paying back the loan as well as continued savings. Installation of 3.3-MW of solar carports at five schools began about a year later. The system’s been in operation since last fall, generating more than 80% of the schools’ energy demand. The project is expected to save the district about $24.4 million over the next 25 years.
Construction, however, wasn’t so easy. School campuses with tight space, trees and among neighborhoods can be challenging sites for solar.
“Most of the district’s schools’ roofs were not oriented well for solar panels,” says Terry Koehne SRVUSD Community Relations Director. “The age of the roofs was also an issue because of concerns about penetrating to anchor the panels.”
The final five schools were selected because of their open parking lots, which allowed space for solar carports. Still, such limited space called for high-capacity modules on a small area. With a module efficiency of 20%, SunPower Corp.’s E-Series solar panels seemed like the right choice. More than 10,000 panels in the system allow generating up to 50% more power than with conventional panels of only 12% to 15% efficiencies.
Parking lot structures also allow using automated panels, which rotate with the sun to maximize exposure. Hence, Bill Kelly, managing director at Sunpower, says the company used both fixed and tracking shade options.
“Four of the five schools have single-axis, elevated Sunpower T0 trackers, which track from east to west and generate about 25% more energy than fixed panels,” he says. “One school’s architecture was especially constrained, so we added fixed rooftop panels as well.”
Kelly says another challenge was working within a tight time frame.
“Because things are usually so busy during the school year, we’re often confined to working during summer break,” he says.
Work began on the project in April 2011 and completed in September. Kelly admits it was tough to get the work done, but the company has experience installing on schools and so has developed a process.
“We do preconstruction planning to make sure materials and labor are in place so we can stay on schedule,” he says. “Also, the schools in this district were particularly modernized, so updated electrical systems and other technology infrastructure made things easier.”
JMC Steel Group’s Atlas Tube division provided 1,200 tons of steel used in the solar carport supports. It also had to meet a tight deadline.
“We were asked to begin delivery within four weeks of receipt of the order,” says Jelani Rucker, director of marketing and business development at JMC Steel. “As one of the few sources for this sized product in North America, it was critical that we delivered, or the project completion date would have been in jeopardy.”
Rucker says the company was able to deliver on time because of its strong relationships with steel coil manufacturers and rail companies.
The total project cost $23 million, but low-interest bonds enabled the district to afford it. Such Qualified School Construction Bonds have been made available for a limited time as part of the federal 2009 American Recovery and Reinvetment Act. SRVUSD was approved to receive $25 million through the program and will pay the money back to a bank through the energy the systems generate — the government will pay back the interest to the bank.
“Also, the current Pacific Gas & Electric (PG&E) rebates for solar energy are generous, and the price of solar panels is relatively low because of the economy,” Koehne says. “Installation costs have also been falling because of the economy, so we felt this was an opportune time to take advantage of the program.”
After about 16 years, the bonds will be paid off and the district will begin realizing an estimated $3 to $5 million per year in energy savings to its General Fund Budget. But the project benefits aren’t all financial. The board also realized the importance of the district modeling environmental stewardship and energy conservation, so it chose a project that will offset 76.3 million lbs of CO2 emissions over 25 years. The project also helped create local jobs, not to mention that the teachers and students are enjoying the shaded parking and better lighting at night.
“SunPower has also started an internship and renewable energy education program, and our students, in turn, have become ambassadors for the solar initiative,” Koehne says.
SunPower uses the systems as educational tools to help students understand solar power. Also, its Solar Academy internship provides opportunities for 16 high school students in the district.
“So far, community response to our solar initiative has been positive,” Koehne says. “People are supportive of the district saving millions in energy costs, particularly in these tough economic times. The district is looking into the possibility of combining the remaining unused funds to provide solar at one additional school.
Many districts in California are turning to solar energy.
“Sunpower plans to installed solar at 90 schools in California,” Kelly says. “Its really rewarding that technology we’ve developed here in California is being used by schools here to save money and get students excited about renewable career opportunities.”