A new solar photovoltaic (PV) array was added on to the Rancho Seco property owned by the Sacramento Municipal Utility District (SMUD) to celebrate the 20 year anniversary of the utility's first major solar installation. PV1 was installed and hooked into the power grid to provide one megawatt (MW) of renewable energy to the Sacramento system. PV6, the anniversary installation, increased the field array capacity to 3.2 MW, enough to power more than 2,200 single-family homes. UniSolar manufactured the modules that went into the panels for PV6. The 3,700 modules purchased were priced at $6 a watt, and fitted into approximately 412 tracking panels that follow the sun across the sky to help gather the maximum amount of solar energy.
"PV1 was one of the first solar arrays in the world."
Sacramento, California - September 3, 2004 [SolarAccess.com]
Modules installed in 1984 are operating at about 80 percent of their original capacity, according to Grant Nelson, who is the project manager for Renewable Generation Assets at SMUD. The new panels aren't meant to replace the original installation, Nelson said, but to aid in power production through updated technology. Researchers from the New Mexico State University have been tracking the performance of the arrays from installation to decommissioning.
"Over the years, as a modules fails totally, we will replace them," he said. "We anticipate, looking at how the performance has dropped over the years, it will probably be about five more years (before SMUD decommissions panels in PV1)."
PV1 was one of the first solar arrays in the world, according to SMUD. Grant said the first array caused a lot of talk because the technology was still fairly new. With the dedication of PV6, the plant now has nearly 5000 solar panels at the on-site array.
Solar energy isn't relegated to the utility's land, however. Part of the company's power load is supplied by distributed generation systems on commercial buildings, homes and parking structures. More than 8.3 MW of power comes from PV arrays in the utility's district.
Distributed generation is a selling point to customers, Grant said, because it takes the power load off of the utility and provides the customer with a personal power source.
SMUD plans to keep improving both the on-site arrays and the distributed generation network, Grant said. By encouraging PV use, the utility hopes to promote the solar market enough to increase local research and development, and perhaps start to bring the prices down on PV production and installation.