winds that often fan wildfires in southern
California.
Macro-scale winds are found in the
larger world wind belts. The trade winds
and the westerlies are examples. The trade
winds are the steadiest of the wind belts,
consistently blowing from the same direction day after day, generally between 5 and
20 degrees latitude. These winds occur in
the United States only in Hawaii and South
Florida. The westerly winds, on the other
hand, are less predictable. They generally
blow from west to east between 30 and 50
degrees latitude and occur throughout the
country between Canada and Mexico.
Micro wind patterns are generally too
unpredictable, too light and variable or
too infrequent for generating power. Wind
machines (windmills and less conventional designs) require a consistent wind with
velocities of about 15 miles per hour (24
km/hr) or greater. (The newest technologies may utilize winds less than 10 mph,
or 16 km/hr.)Thus, macro wind belts offer
the best potential for generating economical electrical energy. Local conditions,
however, may enhance the wind velocity.
Superior geographic locations for wind
energy production in the United States include mountain ridges, gaps and hilltops,
level open plains, high unobstructed plateaus and some coastal regions. Since the
through gaps in the ridges. Called a venturi effect, this phenomenon helps explain
the high wind velocities often experienced
in mountain environments. Such locations
provide excellent sites for wind machines.
Parts of the Rocky Mountains, Sierra
Nevada, northern Cascades, the Appalachians and southern California have excellent potential for wind machine sites. In
Neal Lineback
addition, the Great Plains provide numerous potential sites, although average wind
and Mandy Lineback Gritzner
velocities are somewhat lower.
The use of wind power to generate electricity continues to grow in the United
States. In 2008, the installed wind power
capacity increased by 50 percent. By comparison, the global growth rate for wind
energy is 28.8 percent.
A U.S. Treasury grant program that
By the end of 2009, the United States
funds renewable energy development,
had a generating capacity of wind energy
including wind and solar projects, will exestimated at just over 35,000 megawatts
pire at the end of 2010. Without it, compaof power, enough to power 9.7 million
nies in the renewable energy business may
homes. That installed capacity provides
suffer and wind energy development may
approximately 2 percent of the overall
face setbacks.
electricity in the United States.
While wind energy is underutilized in
The Global Wind Energy Council rethis country, this important resource deported in 2009 that the United States is the
serves attention. Environmental problems
world leader in installed wind power caassociated with wind energy are relativepacity (35,159 MW) followed by Germany
ly few. Unlike fossil fuel power sources,
(25,777 MW), China (25,104 MW), Spain
wind energy does not burn fuel or pollute
(19,149 MW) and India (10,925 MW).
According to Reuters, there are about
the air.
85,000 U.S. jobs associated
Some places on the earth
Average Annual Windspeed
with wind energy. The top
have enough wind energy to
five states generating wind
supply a considerable share
©2010
power are Texas (9,728 MW),
of electric energy needs.
Iowa (3,670 MW), California
Such windy regions could
(2,739 MW), Oregon (2,095
potentially supply huge porMW) and Washington (1,964
tions of the U.S. electric conMW). If wind power growth
sumption. What is the geogcontinues at the same rates,
raphy of wind potential?
the United States could genWind is a function of diferate 20 percent of its elecfering air pressures at or
tricity from wind by 2030.
near the earth’s surface. As
That, however, may be
air moves between high and
impossible without suplow pressure areas, the report from the federal govsulting wind equalizes the
0–11.5 mph
ernment. The program that
pressure differences. Conse13.4–21.1 mph
0
400 mi
the U.S. Congress failed to
quently, winds blow from ar11.51–13.39 mph
0
400 km
extend recently funds up
eas of high pressure toward
Geography in the News 12/24/10
Source: Home Power, 1991
D. Lambert/ T.Smith
to 30 percent of the cost of
areas of low pressure.
alternative energy projects.
Different scales of winds
Sources: GITN #314, “Blowin’ in the Wind,” February 2, 1995; http://
Without those monies, the
occur. Micro-scale winds are
www.gwec.net/fileadmin/documents/PressReleases/PR_2010/Annex%20
U.S. wind energy industry
local winds, such as daily
stats%20PR%202009.pdf; and http://www.reuters.com/article/idUSN221
may be in real trouble—and
land and sea breezes along
1296320100126?type=marketsNews
not only business will suffer,
the coast in the summer, and
but the environment too.
mountain winds, such as chiAnd that is Geography in the News™. Denooks and katabatic winds. Chinooks are
earth’s rough surface creates drag (friccember 24, 2010. #1073.
warm, dry winter winds that periodically
tion) on wind, wind machines placed high
Co-authors are Neal Lineback, Appalachian
descend the Rocky Mountains, literally
above the surrounding land surface are
State University Professor Emeritus of
evaporating the snow cover. (“Chinook”
able to capture more wind energy.
Geography, and Geographer Mandy Lineback
means “snow-eater”). Examples of kataHigh mountain ridges offer an advanGritzner. University News Director Jane
batic winds are winds that descend from
tage, creating create air dams that result in
Nicholson serves as technical editor.
high plateaus, including the Santa Ana
increased wind velocity as the air funnels
Geography
In The
News™
INCLEMENT
FUTURE FOR U.S.
WIND ENERGY
©2010 Maps.com