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Running on Wind?

March-April 2008

Michael B. McElroy’s research group has launched an extensive program to define the potential of wind power as a source of electricity worldwide. The study capitalizes on a unique meteorology database developed by the Global Modeling and Assimilation Office at NASA’s Goddard Space Flight Center. Validated by hundreds of regional and global air-quality studies, this data resource refines understanding of meteorologically dependent new energy sources, notably wind and solar, and can powerfully inform national and international strategies for their exploitation.

The database provides a record of wind activity every three hours averaged over a spatial grid with individual grid elements measuring 1-degree longitude by 1-degree latitude (equivalent to the area defined by a 100-kilometer by 100-kilometer square at mid-latitudes, less at high latitudes, more at low latitudes) covering the entire globe. The McElroy group uses these data to calculate the electricity that could be generated by deploying specific wind turbines. Samples of preliminary results for the United States appear in the accompanying figures. They show, for example, that even for such populous, high-consumption states as California, Texas, and Florida, the potential for electricity generated by wind far exceeds total current consumption.

The results displayed assume deployment of 1.5-megawatt turbines throughout the entire country, excluding unsuitable regions such as urban and forested areas. The study identifies the variability of the wind source, allowing researchers to explore how it could be exploited in an integrated electrical system that must match variable supply to demand. It is worth noting in this context that the batteries on an expanded fleet of plug-in hybrid vehicles could provide an important opportunity for storage of electricity at times when the potential production might exceed the immediate demand. Future work will incorporate realistic economic constraints, such as: costs for installing turbines in specific regions and for extending the electrical grid to distribute the added power; electricity prices; and different turbine designs. The studies could also take into account the effects of future global climate change.

The data presented define the potential or maximum power that could be generated using wind. Although these results are restricted to onshore deployment in the United States, the study identifies the potential for wind power offshore as well, and for the globe as a whole. The potential U.S. supply could be increased by about 20 percent if turbines were installed offshore within viable distances from the coast and sea depths, notably in the Northeast and on the West Coast. To date, it has proven difficult to site wind farms in densely populated coastal regions such as Nantucket Sound. There is minimal opposition, however, to placing turbines in more sparsely populated regions of the continental interior, where landowners are now receiving annual rents of up to $3,000 for the installation of a single turbine on their property (siting that has minimal impact on other uses of the real estate).

The accompanying figures were prepared by graduate student Xi Lu, using 2001 as a representative model year.