Batteries that store wind power will be tested with the help of the Modesto Irrigation District.
Its board voted 5-0 Tuesday to work with Primus Power Corp. of Alameda, which got a $14 million federal grant last year to develop the technology.
It will be tested on a small scale at a San Ramon laboratory for two years, using information from the district about power demand and other factors.
If the idea pans out, enough batteries to store 25 megawatts of power will be installed at an MID substation and evaluated for three more years.
The testing will cost the district nothing. It could buy batteries for long-term use if the technology proves worthwhile.
The batteries would solve the main drawback of wind power: The breezes tend to blow at times that do not match peak electricity use, which is mainly summer afternoons and evenings. This has prompted the MID to invest heavily in natural gas-fueled plants to provide backup power.
The batteries, using an electrochemical process that Primus is keeping secret, would be housed in boxes similar to the cargo containers on trucks, trains and ships.
They could be cheaper than a backup gas plant and would take up far less space, said Roger Van Hoy, assistant general manager for electric resources at the MID.
"(The testing) would try to make it utility-scale and pretty cheap," he said.
The MID is a leader in wind generation, getting 100 megawatts from turbines in Solano County and Washington state. This amounts to 12 percent of the total supply and would double with planned additions this year and next year.
Wind power coming in on transmission lines would charge the batteries in a process roughly similar to how a cell phone is charged, a Primus executive said last year.
The batteries would discharge the power over three hours at the full 25-megawatt flow, or longer if the flow is reduced.
The batteries also can store solar power, which is a small but growing part of the district's resources.
MID General Manager Allen Short said the state eventually could require utilities to have storage systems for renewable power.
The grant to Primus came from the U.S. Department of Energy and was part of the $787 billion federal economic stimulus package of 2009.
The Energy Department is seeking alternatives to the fossil-fuel burning believed to be changing the global climate.
Bee staff writer John Holland can be reached at 578-2385 or firstname.lastname@example.org.