Green Schools | News
San Lorenzo Unified School District To Save 4.5 Million with Solar Energy
- By Dian Schaffhauser
The San Lorenzo Unified School District in Northern California has tapped a school modernization bond to install its first solar project. Built by Chevron Energy Solutions, a set of solar canopies in multiple parking lots throughout the district will generate 1,021 kilowatts of electricity.
The bond measure, which raised $83 million for facility additions and renovations, included funds for energy management and conservation. Besides the solar installations, the district also implemented new energy management and lighting systems in new buildings and retrofitted existing buildings. It estimates that it will save $300,000 to $400,000 per year on its annual electric bill, which has traditionally been over $700,000 a year. The project is expected to have a 12-year payback at a maximum. Over the lifespan of the project, San Lorenzo expects to save $4.5 million.
After obtaining an independent analysis of potential approaches to the solar project the district chose parking shade structures instead of rooftop units because the latter may have required "expensive" roof structure improvements and could conflict with roof repairs and future reroofing projects. According to a September 2011 presentation, the parking structures would be easier to maintain, but had to meet requirements for fire truck access.
The same analysis determined that the optimum sizing for a solar project would meet between 75 and 80 percent of the district's current energy needs. Over-sizing--generating enough power to sell back to the utility company--was considered "a very poor investment."
The district also chose to pay for the system and handle or contract out its on-going maintenance and operation rather than setting up a power purchase agreement with a third-party. In the latter scenario, a district contracts for a set price with a company that builds, owns, and operates the solar installation.
Although the district and its advisor Kenwood Energy solicited bids from several firms, only two came through with proposals. San Lorenzo chose Chevron for the project because "they have the most experience in this area," district staff explained during a school board meeting. The work was estimated to cost up to $6.5 million with about a million dollars being reimbursed through a California state solar initiative.
"This project fulfills our commitment to the voters of this community, who have consistently entrusted us with an ambitious investment in our district's facilities," said Superintendent Dennis Byas. "With the completion of our solar canopies, we have not only been able to bring our schools into the 21st century, but we have used these bond dollars in a way that will ultimately benefit our students, our teachers, and our local community."
Dian Schaffhauser is a former senior contributing editor for 1105 Media's education publications THE Journal, Campus Technology and Spaces4Learning.