In 2007, the U.S. added 5.3GW of wind power. See latest (MAY 2008) DOE report - (pdf file).

Expect a lot more in the future.

Many states have programs in place called RPS (renewable portfolio standards); these are mandates for each state seeking a certain amount of energy from renewable energy sources. Roughly 35% of new energy added to the grid last year came from wind. It is important to understand how RPS mandates could drive the demand side for the US wind industry. 

Solar plays a smaller part in this growth and will for the next 5-7 years out, based on current growth.

Most wind installations yield roughly 30% of their nameplate capacity due to the variance in wind availability. Thus a 1 gigawatt (1,000 megawatt) wind farm will, over its operating life, yield roughly 300 megawatts per hour baseload equivalent.

Below is a chart of the RPS mandates from the various states compiled by the union of concerned scientists. 

For the next 5 years there will be demand for approximately 20GW of extra renewable power. If one cedes 5GW to solar, biomass and geothermal over that period, we are left with 15GW of wind power. At a rated wind tower capacity of 30%, that equates to a need for 50GW of nameplate capacity over the next 5 years, or 10GW of installations per year. 

At roughly $2.1m per installed Megawatt of wind capacity, one could assume a yearly market for wind of $2.1x10=$22 billion/year. 

The DOE (Department of Energy) has some great reading on the matter: http://www1.eere.energy.gov/windandhydro/.

One point of interest for wind bulls should be the fact that 225 GW of nameplate capacity is in the interconnection queue, waiting for approval to build and connect over the next few years. Not all of that will be installed or come online. That 225 GW of development would equate to roughly 67.5 GW of baseload equivalent power or 6.7% of current grid power.

The US grid currently has approximately 1,000 GW of capacity. See: http://www.eia.doe.gov/cneaf/electricity/epa/figes2.html

As more capacity comes online and RPS standards are met, Wind will continue to become an important part of the generating asset mix. Wind will push gas out of the mix for the near future. Beating coal as a power source from a non-carbon perspective will take CSP. Expect massive HVDC transmission projects in the next few years as well.

From a global market perspective, about 20% of wind cost is transportation, so wind will remain mostly a regional and less international phenomenon for manufacturers and developers. Makers of Gearboxes and hobbing tools will be the exception to this.

Globally, wind has a long way to go.

There is 4,300 GW of installed capacity globally, growing just below the rate of gross world product. At 4%, that equates to 172GW baseload or 573 GW of a wind equivalent installation, potentially addressable market annually.

Wind won’t capture all of this, but a 35% share equates to a $421 billion annual global opportunity.