Photo: Hawaiian Electric Co.
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The potential of wind power to help meet America's
growing demand for electricity is staggering: According
to a definitive 1993 study by the Pacific Northwest
National Laboratory, areas of strong winds cover about 6
percent of the mainland states and, if exploited, could
supply more than current U.S. electricity consumption.
Conversely, just 0.6 percent of the land of the
contiguous 48 states would have to be developed with
wind turbine farms to provide 15 percent of the nation's
electricity requirements. Even then, less than 5 percent
of the developed land would actually be occupied by wind
turbines, associated electrical equipment, and access
roads. In most cases, existing land uses, such as
farming and ranching, could remain as they are now.
Harnessing this potential could make an enormous
contribution to reducing the United States' dependence
on imported oil for power generation, as well as helping
to stem an increasing dependence on imported liquefied
natural gas. Adding wind power to the grid can help
stabilize electricity prices, too, in the face of
escalating fuel costs, with oil topping US $72/bbl and
natural gas prices at all-time highs. Wind power, in
contrast to oil and natural gas, is both price-competitive and
price-stable, and that
stability can help provide a cap on the price of
electricity. And let's not forget that wind power is a
whole lot cleaner than fossil fuels—be they imported
oil or domestic coal.
Yet one often hears questions related to wind power's
intermittent nature; unavoidably, electricity is
generated only when the wind blows. Can the power grid
handle massive amounts of variable production? Can wind
energy be delivered where it's needed when it's needed?
Can wind energy harnessed at times of low demand be
stored for high-demand periods? Can new storage
technologies be devised so that wind energy would
become, in effect, dispatchable? The answer to all of
these questions is yes, and in some cases the answers
are already in practice.
Wind-energy and power-transmission technologies are
already adapting to accommodate the impressive growth of
wind power. Large semiconductor devices referred to
collectively as power electronics are, for example,
enabling wind farms to provide rapid response to
fluctuations in grid frequency and voltage. This is one
of many reasons why grid studies consistently estimate
that the cost of integrating wind power will be low.
However, integration costs will rise when one considers
small power grids or high proportions of wind power in a
grid. In such cases, power electronics devices can be
combined with energy storage technologies that operate
over a range of time scales to manage the shifts in wind
power production. In fact, a growing number of
innovative energy storage options are providing grid
operators ways to dispatch wind power in the same way
they do with thermal generating plants. Continental
supergrids eventually will help, too, by distributing
wind-generated power across whole regions, balancing
regions where the wind happens to be blowing with those
that may be becalmed, while simultaneously spreading the
burden of providing backup power.
What follows is a taste of the technology and policy
strategies that are already helping to give wind power
new strategic importance, and which will be critical to
sustaining its growth in coming decades.