As California works toward the goal of getting 30 percent of its electricity from renewable sources by 2020, city and county agencies are exploring new sources of energy and embracing new technologies.
The transit authority in Silicon Valley announced on Friday, May 15, that it is looking to give itself a greener profile. It's not doing it with biofuel buses or maintenance trucks that run on ethanol. Instead, it's running a test project with solar array manufacturer Skyline Solar to harness solar energy. The Santa Clara Valley Transportation Authority unveiled a new 27-kilowatt High Gain Solar array at its San Jose, Calif., bus maintenance and operations facility. The system works like a typical business or residential solar power system, and the electricity produced through the project helps offset the power the VTA purchases from local utility Pacific Gas & Electric.
Skyline Solar's design uses bent sheet metal to reflect the sun's rays onto a silicon collector, which the VTA says solves two main barriers to solar energy--cost and scalability. Using the monocrystalline silicon cells and tracking technology to increase the amount of energy captured, the amount of silicon required is reduced by 90 percent. This design cuts costs further by using globally available manufacturing facilities, like automotive factories, to produce the racks and mounting systems.
Here, looking down the reflective sheet metal of the new solar array, you can see the two narrow silicon collectors at the top left and the top right.
Skyline Solar says it enhances the efficiency of its solar systems by reflecting sunlight, and using convection cooling, string and shadow management, tracking capabilities, and a streamlined installation process to drive higher energy gains.
The HGS system, which uses single-axis tracking, achieves 10 times the energy out of a gram of silicon by tracking the sun and concentrating light onto solar cells. Sunlight reflected off of formed, coated sheet metal is focused onto the narrow area of solar collectors.
San Jose Mayor Chuck Reed, who spoke at Friday's event, says that Silicon Valley has a tremendous opportunity for innovation in energy technology, and that the area must be a leader in fostering these emerging partnerships.
In a separate announcement, on May 8, Congressman Mike Honda, from the 15th Congressional District, touted the county's initiative to provide cheaper and cleaner energy at the County 911 Communications facility in San Jose where Santa Clara County announced the installation of a fuel cell system. The 25-kilowatt system converts fuel directly into electricity through a clean electrochemical process rather than combustion. This currently serves as a backup power system for the facility, to provide redundancy and ensure it is never without power. It also ensures the facility does not have to rely on someone else to support their emergency services.
Solid-oxide fuel cells use specially engineered ceramic plates, catalysts, and high temperature to convert fuel directly into electricity through a clean electrochemical process rather than combustion. The fuel cells currently run on propane, but can easily be configured to accept other fuels. Eventually, the county hopes to run the fuel cells using only water.
"Projects like these," Honda said, "where Congress, Santa Clara County, the Department of Energy, and Silicon Valley partnered together to power the 911 Communications Facility, exemplify how the public and private sectors can effectively come together for the common good."
Officials hope that by adopting these technologies, governments will demonstrate their effectiveness and scalability, fostering wider uses and applications.