Google, Inc. and two Japanese firms have joined GE Energy Financial Services and Caithness Energy as owners of the world’s largest wind farm.

If any wind farm is big enough to split five ways, it would be Shepherd’s Flat. The project will stretch across 30 square miles in Morrow and Gilliam counties in north-central Oregon and generate enough electricity to power 235,000 U.S. homes.

Today, Google announced it is putting $100 million into the project, and two Japanese companies, ITOCHU’s Tyr Energy and Sumitomo Corp., together will kick in another $400 million. Apparently, these companies believe there’s money in wind farm development.

Maybe because there’s a growing market for renewable energy in California. Shepherds Flat’s 835 megawatts will all be going to Southern California Edison to help the utility meet a new 33 percent renewable power by 2020 mandate.

California already buys about half the wind energy developed in Oregon since 1998. A new rule caps the amount of renewable energy credits California can import from other states, but the recent increase in the state’s renewable standard will leave room for more energy development in Oregon.

True, Oregon is already on the verge of having more wind energy than the grid can handle (with major gridlock in the spring, when the wind is blowing and snow melt sends lots of water flowing through the dams). The wind generating capacity in the Northwest has grown from 250 megawatts in 2005 to 3,500 today. And there is more on the way. Regional power manager Bonneville Power Administration has backed away from a plan to shut down wind turbines when there’s too much renewable energy, but it hasn’t found alternative short-term solution.

Are renewable energy tax credits and subsidies to blame for the renewable energy crunch? Shepherds Flat has been criticized for “double dipping” into federal and state subsidies and claiming tax money beyond the value of the carbon reductions the project offers. The Oregonian found a White House memo that cited $1.2 billion in federal, state and local subsidies for the project – or 65 percent of the $1.9 billion cost.

The O’s energy reporter Ted Sickinger has been on this case for awhile now. He even calculated the total cost to taxpayers for the Shepherds Flat project to be $34 million per job. Though that’s only counting the 35 permanent, full-time jobs, and doesn’t account for the economic multiplier effect, 400 temporary jobs, or the $100 million in taxes revenue for Gilliam and Morrow counties over the next 15 years. And, it should be noted, amid controversy over state spending for wind projects that might not even need the help, Oregon has dramatically scaled back state subsidies for renewable energy development.