The Modesto Irrigation District is boosting its use of wind energy — and adding conventional power for times when the breezes are not blowing.
The district board voted 5-0 Tuesday to buy at least half of the output of a 100-megawatt wind system planned for the Columbia River Gorge in Oregon.
The board also voted unanimously to move ahead with a $78 million expansion of the MID's gas-fueled power plant on Woodland Avenue in Modesto, adding 49.6 megawatts.
The wind project, expected to be operating by late 2010, will bring the district closer to its goal of producing 20 percent of its power from renewable sources by 2017. It stands at 12 percent, mainly from wind turbines in Solano County and Washington state, and would reach 16 percent with the new project.
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It may be a moving target: State lawmakers are considering a 33 percent renewable mandate by 2020.
The MID will pay 13 to 16 cents per kilowatt-hour for the Oregon wind power over 20 years, from turbines to be installed by Iberdrola Renewables Inc., based in Portland.
The MID's cost for gas- fueled plants is 9 to 10 cents per kilowatt-hour, General Manager Allen Short said.
A utility in the Pacific Northwest plans to use the rest of the wind project's output, but the MID can buy it if that plan falls through.
The power will be delivered on existing transmission lines between Oregon and California. The MID and other utilities are planning new, controversial lines for potential renewable power from Lassen County.
Natural gas engines ordered
For the Woodland Avenue expansion, the district already has ordered six engines that burn natural gas. The $78 million total includes the engines, plant construction, design and several other costs.
The engines, expected to be running by May 2011, are designed to ramp up in 4-megawatt increments. That will allow the MID to fill gaps in the wind power without turning on the entire system on Woodland.
"What these units will do is give us fast, very flexible generation," project manager Richard Smith said.
Wind energy, although valued for its lack of pollution or fuel demand, can be an unsteady source. Sometimes the wind blows too little to make power, and sometimes it blows too hard for the turbines to operate.
The renewable mandate also allows sources such as solar, geothermal, biomass and small hydroelectric systems.
The board Tuesday added 3.3 megawatts to the mix from a hydro plant at New Hogan Reservoir on the Calaveras River. The MID built it in 1986 and has been selling the power to Pacific Gas & Electric Co., but the district has opted to use the output.
MID officials Tuesday complained once again that Don Pedro Reservoir's large hydro plant does not count toward the renewable goal, even though many people see it as clean power.
"It's a very expensive decision that forces us into some of the exotic, very expensive electricity generation," Director John Kidd said.
Bee staff writer John Holland can be reached at firstname.lastname@example.org or 578-2385.