Tucson Electric Power Co. has agreed to purchase nearly 160 megawatts of renewable energy from plants planned by independent producers, which would increase roughly tenfold the utility's current renewable-energy generating capacity.

The agreements cover 10 solar power plants to be built locally, plus a local landfill-gas generation project and a new wind farm in New Mexico.

Together, the projects would generate nearly 160 megawatts, enough renewable energy to power more than 30,000 Tucson homes, TEP said.

TEP has submitted the agreements to the Arizona Corporation Commission for review.

The commission's approval would allow developers of the systems to proceed with efforts to finalize financing, secure land rights and clear other necessary hurdles, with a goal of completing the projects in time to begin providing power in 2011 or 2012, TEP said.

"These agreements are the next step in our development of local utility-scale renewable power projects that will help us achieve our renewable energy goals," Paul Bonavia, chairman and CEO of TEP and its parent company, UniSource Energy Corp., said in prepared remarks.

State regulators have mandated that regulated utilities boost their use of renewables, from 2.5 percent of their retail power needs this year to 15 percent by 2025.

Four of the solar projects are to be built at a recently announced "Solar Zone," a 200-acre site at the University of Arizona Science and Technology Park, on South Rita Road just east of Interstate 10.

Other projects are slated for other locations in the Tucson area or planned for local sites not yet determined, TEP said in its filing with the Corporation Commission.

The power purchase agreements will have a 20-year term and a fixed price.

Here's a look at companies planning the renewable-energy plants and their current plans for projects:

• Amonix Solar: The Seal Beach, Calif., firm specializes in concentrating photovoltaic technology, which uses lenses to focus light on solar cells. Amonix plans a 2 MW project at the UA tech park and a 12 MW facility at a rock quarry on South Swan Road, just north of East Old Vail road.

• Foresight Solar: The company, based in Kent, England, will develop two projects using single-axis tracking photovoltaic systems, which track the sun for maximum light collection. Foresight plans a 4 MW plant at the UA tech park. The second project, a 12 MW installation, will be built in TEP's service territory, but its location has not yet been determined.

• Avalon Solar: Albuquerque-based Avalon plans a 35 MW fixed photovoltaic project on fallow farm land held by Tucson Water in Marana.

• Emcore Solar: The Albuquerque-based developer of concentrated photovoltaic systems plans a 2 MW system at the UA tech park.

• NRG Solar: The Utah-based company plans a 25 MW project at an as-yet undetermined site within TEP territory.

• CTC Solar: The Connecticut company plans a 5 MW, fixed photovoltaic installation at the UA tech park.

• Solon Solar: The German company, which has a factory in Tucson, plans two 5 MW photovoltaic projects using single-axis tracking technology. The sites have not yet been determined.

• Torch Energy: The Houston company will develop a 50 MW wind project near Deming, N.M.

• Sexton Energy LLC, based near Chicago, will develop a landfill gas project at Pima County's Tangerine Landfill, after the county awarded the gas rights to the company. The project will have an expected capacity of 1.1 to 2.2 MW, depending on actual gas output.

Contact Assistant Business Editor David Wichner at dwichner@azstarnet.com or 573-4181.