Is the wind power sector picking up? On Monday, Google venture capital arm announced a $38.8 million investment in two wind farms in North Dakota. It s the company s first direct investment in a utility-scale renewable energy project, and the projects in question generate enough energy to power 55,000 homes.

In 2009, 10,000 megawatts of new wind power were installed in the US the largest installation year ever, according to the American Wind Energy Association (AWEA). Wind energy still provides just 1.8% of all U.S. power, but provided 39% of new generating capacity in 2009.

The sector held up relatively well through 2009 because there were a lot of orders in the pipeline just when the financial crisis hit, says Murray Rosenblith, a fund manager for the New Alternatives Fund (NALFX), which invests in companies whose products benefit the environment. Now, however, new orders have stalled, and financing for new projects is difficult to find, Rosenblith says.

New projects are also facing opposition from not in my backyard groups as well as from some members of Congress concerned about stimulus money supporting foreign companies, Rosenblith says. General Electric is the top supplier of wind turbines in the U.S., but the largest supplier world-wide, Vestas Wind Systems, is based in Denmark, and many other major players in the field are also based outside the U.S.

A shift in focus from onshore to offshore wind projects could further shake up the industry, says Nicholas Heymann, the director of global industrial infrastructure research at Sterne, Agee & Leach. Offshore projects are initially more expensive, but because wind typically blows more hours at sea than on land, and the different, gearless turbines used in offshore projects can generate more power than those used onshore, offshore projects can be 35% to 40% more productive than onshore farms, Heymann says.

Offshore or on dry land, wind power projects are capital-intensive and take years to generate profits even without the additional scrutiny the sector currently faces, Rosenblith says. There is very little potential for a fast profit in alternative energy, he says. It is definitely a place for patient, long-term investors.

For those patient investors, here s a look at how four major players in the American wind power industry are doing now:

FPL Group

FPL Group two subsidiaries are Florida Power and Light and NextEra Energy Resources, the developer of the North Dakota wind farm Google is investing in. NextEra, based in Juno Beach, Fla., is the top wind-power owner in the U.S., according to the AWEA. In the first quarter of 2010, NextEra accounted for half of FPL s total earnings per share less than in the previous year s first quarter, due in part to less-windy conditions. Wind power accounts for about 42% of NextEra s total power generation.

In its first-quarter earnings report last week, the company revised its estimate of new wind capacity building for 2010 downward from 1,000 megawatts to 600 to 850 megawatts. Near term, stalled climate change legislation and reduced demand for energy because of the recession will slow the company s development of new capacity, says Tim Winter, an analyst at Gabelli & Company. Longer term, a strong pipeline of potential new products leaves the company positioned for growth, Winter says.

Xcel, based in Minnesota and serving eight Western and Midwestern states, is the utility with the most wind power capacity in the U.S., according to the AWEA. Most of this capacity is bought rather than owned, but altogether the company s wind capacity matches 15% of its projected 2010 peak demand for power. The company reported ongoing earnings of 42 cents a share for the first quarter of 2010, up from 38 cents a share the previous year. This performance was in line with expectations, and the stock is a relative safe haven, according to a report by Michael Worms, an analyst at BMO Capital Markets.

General Electric

General Electric commanded 43% of the U.S. turbine market as of 2008, according to the Department of Energy, but wind power still isn t a large portion of GE s overall business. GE s total revenues for 2009 were $157 billion, with its GE Energy division contributing $37 billion. Wind turbine sales in 2009 were about $6.4 billion, Heymann says. GE has grown its wind-turbine business approximately tenfold since its initial purchase of Enron Wind Corporation s assets in 2002. Now the wind business is moving into a more steady, moderate growth environment, Heymann says. GE Energy has dominated the U.S. terrestrial turbine market, and is just now beginning to offer offshore turbines, but should regroup pretty quickly to capture this growing segment of the wind power market, he says.

Vestas Wind Systems

Vestas, a pure-play wind company based in Denmark, is the world s largest turbine maker, and won a 13% share of the U.S. market in 2008, according to the DOE s most recent study of the wind-power market. Vestas should hold on to its dominant market position in the transition to offshore projects, Heymann says. The 112-year-old company delivered its best-ever financial results in 2009, with $6.36 billion in revenue, but reported a loss for the first quarter of 2010, on a 32% year-over-year decline in revenue. The company said it expects to generate the bulk of its revenue and profit in the second half of the year.