A new analysis conducted by the National Renewable Energy Laboratory and consulting firm AWS Truewind estimates that the energy potential of US wind resources has tripled since the last estimate in 1993. The report shows that current wind technology could generate 37 trillion kilowatt hours of electricity per year, which is more than a threefold increase from an estimated 10.8 trillion kilowatt hours from the previous analysis by the Pacific Northwest National Laboratory. No, the winds aren’t really blowing that much harder, the increase has come from technological advancements in wind turbines rather than a better understanding of the national windscape. The new data are from heights of 80 and 100 meters whereas the previous data was taken from a height of 50 meters. The most recent wind turbine designs have 80+ meter hub heights and are capable of generating more energy than shorter turbines because higher altitudes are less subject to wind shear effects from friction at Earth’s surface. And the designs are continually evolving – Norway is currently building the world’s largest wind turbine – a mammoth 10 megawatt, 162.5 meter machine.
The US wind resource map below shows the new predicted average annual wind speeds at a height of 80 meters.
US 80 meter Wind Resource Map
In particular, Texas has the most abundant wind energy resource of any US state.
Texas 80 meter Wind Resource Map
Despite this increase in our estimated wind resource, the many challenges of integrating more wind energy into our electricity generation mix still remain. Clearly, the estimated wind resource is abundant enough to supply a significant portion of electricity, yet the contribution of wind in the generation mix is very small (though is growing fast). In 2008, total US electricity net generation was 4.1 trillion kilowatt hours and wind contributed just 0.052 trillion kilowatt hours, according to the Energy Information Administration’s 2008 Annual Energy Review. The potential for substantial growth is well recognized, and in July 2008, the Department of Energy released a report analyzing a scenario to increase wind energy’s contribution to US electricity generation to 20% by 2030.
There are technical and policy barriers to achieving this scenario. One of the main technical barriers is transmission. As indicated on the above map, much of the wind resource is located in the middle of the country and away from urban population centers. New and substantial investment in transmission lines (around $43 billion!) is required to deliver the energy from where the wind blows to where it is demanded. Perhaps an even more difficult problem is the task of integrating a highly intermittent resource into the power grid without compromising stability. Investment in wind development is crucial, and can be stimulated by US policymakers extending existing production and investment tax credits or solidifying renewable portfolio standards.
Our national wind resource is abundant (even more so than previously was thought), yet significant technological innovation and forward-looking, long-term policy is needed before wind energy can become a major contributor to electricity generation.
Energy, Technology, & Policy 
Thanks for the update on the new 80 meter wind maps. I wanted comment on the barriers you mentioned, specifically transmission and grid integration.
The best figure I was able to find on cost of adding sufficient 765kV capacity to generate at least 20% of the US electricity production from wind was $610 billion, from an AEP whitepaper on wind transmission. This was calculated assuming 19,000 miles of new 765kV wires at a cost of $2.6MM/Mile and 20% extra for station integration. This sounds like a lot, but it needs to be put in context. Between 1956 and 1991 we spent $129 billion dollars on the interstate highway system, which would be about $425 billion in 2006 dollars. So for 15% of the cost of our entire interstate highway system we could have a new state of the art wind transmission network. The problem isn’t cost; it is political will and long-term thinking from our elected officials. We need another Eisenhower.
As for integration issues, the EWEA Economics of Wind Report states, “At wind energy penetrations of up to 20% of gross demand, system operating costs increase by about 1-4 €/MWh of wind generation…additional grid extension/reinforcement costs are in the range of 0.1 to 5 €/MWh.” This means that the cost of wind integration for up to 20% of power generation from wind would be €1.1-9/MWh or $1.5-12.2/MWh. This further translates to 0.15-1.22 cents/KWh. This is eminently affordable and represents only 5-20% of the cost of the wind. So integration issues are just an excuse to stand behind when advocating against wind that is easily disproven by what the Europeans have already accomplished.
Sources:
Click to access WindTransmissionVisionWhitePaper.pdf
Neuharth, Al (2006-06-23). “Traveling interstates is our sixth freedom”. USA TODAY.
http://www.ewea.org/fileadmin/ewea_documents/documents/publications/reports/Economics_of_Wind_Main_Report_FINAL-lr.pdf (p.94,95)
Excellent blog entry on the increased potential of wind energy in America. I’d like to add an update on the policy side of the picture. You noted that policymakers play a crucial role in stimulating wind investment through tax credits. However, in at least one state of the Union, policymakers are likely to pass a bill including a wind tax instead of a wind credit.
As you can see from your updated wind map, Wyoming is one of several states which could greatly benefit from increased investment in wind energy. But Democratic governor Dave Freudenthal has recently introduced bill which would enact a $3/MWH tax on wind energy come 2012. Proponents of the measure argue (1) that the development of wind farms exacts a toll on local governments (maintenance of roads, etc) (2) that other forms of energy are taxed and wind should not be an exception and (3) the tax increases the state’s tax base and would raise $11.5 million each year at current production rates.
Supporters of wind energy investment are alarmed. The taxation of wind energy has not been a large issue in the past, but even when the federal production tax credit (PTC) is taken away the American Wind Energy Association reports a great drop in national wind investment: drops of 70-90% in years when the credit lapses, and gains of up to 100% in years with the tax credit.
Government incentives are key to the growth of this industry. The enactment of an excise tax on wind could highly discourage wind investment in Wyoming, especially since other windy states are offering tax credits and other incentives.
It appears that the Wyoming Wind Tax bill will pass, largely because the tax is relatively small and legislators want to be able to regulate wind energy in the future.
Sources:
Joyce, Matt (2010-02-14). “Wyoming considers becoming first state to tax wind energy production”. The Washington Post.
Frosch, Dan (2010-02-20). “In Windswept Wyoming, a Debate Swirls on Taxing Wind Industry”. The New York Times.
“Wind Energy For a New Era” by the American Wind Energy Association, available at : http://www.newwindagenda.org/documents/Wind_Agenda_Report.pdf
Pelzer, Jeremy (2010-02-24). “Wyoming wind energy policy likely to be set after session”.
Billings Gazette.