"Environmental Science Class"[img]2012q1/ct_etoefm_etoeflistz_1592_20121[/img] [

[Narrator] Listen to part of a lecture in an environmental science class. The professor is talking about
wind power.
[Professor]
    Today I want to talk with you about another renewable source of energy... wind power. This isn’t a new  Q6
concept. In fact, wind has been used for centuries to pump water and launch sailing vessels. But more
recently, wind power has been used to generate electricity.
    By the year 2000, California was using, maybe 15,000 wind turbines to produce about 400
megawatts of electricity. And that was happening at a cost that would be considered competitive with
coal or nuclear power. And, although California currently leads the United States in harnessing wind
power, there are several other areas that also hold considerable potential for increased production.
Texas and the Dakotas alone have enough wind potential to power the nation, but, since the winds
there are so variable, well, wind power alone would be unreliable as a primary source of continuous
energy. Nevertheless, it could be used as a secondary resource, along with fossil fuels. The strong and  Q7
steady winds of the Pacific Northwest, especially in the Columbia River Basin...  these winds would be
ideal as a supplement to hydroelectric power when the  river is experiencing periods of low water levels.
Studies by the U.S. Department of Energy indicate that wind power generated from the Great  Plains in
the middle of the country could supply the continental United States with almost... 75 percent of the
electricity required for the region.
    In another section of the same report, it was noted that wind power is the world’s fastest growing
energy source. Since 1998, the capacity for wind energy has increased by more than 35 percent worldwide.
    And improvements in wind turbine technology in the past couple of decades has improved efficiency,
cutting the cost dramatically, from roughly 40 cents to about 4 cents per kilowatt hour, and a new
turbine design is being tested with a lower torque, so that may actually move the price closer to 3 cents.
Europe currently accounts for ever 17... , Oh, sorry that’s 70...  seven-zero percent of the world’s  Q8
wind power. India, China, Germany, Denmark, Italy, and Spain have published plans for major
increases in  wind-generated electricity projects in the next few years, and recent interest and exploration
have been initiated in the United Kingdom and Brazil. Remote areas, especially islands, and other
regions at a distance from electrical grids are vigorously exploring wind options. Clearly, the global
implications not only for cheap energy but also for clean energy could be enormous. And, in some
areas, the consumers are even willing to pay a subsidy for the pollution-free energy that wind provides
their communities. In Colorado, for instance, through a program called wind source, about 10,000 customers
pay an additional $2.50 per month for every 100-killowatt hours of wind power. Legislation in
several states in the United States now requires utility companies to guarantee that a percentage of
their electricity will be generated from renewable sources like wind power.
    Of course, there are some problems associated with wind power that do need to be considered. The  Q9
blades on the turbines present a hazard to migrating birds.In some cases, the vibrations interfere with
television reception in the area. And, there have been objections to wind farms because. they produce
noise and because they’re not visually appealing to residents nearby. So, in addition to the studies to
improve turbine design and energy efficiency, some of the attendant problems also require research
and development. Regarding the noise, let me mention that design modifications, basically modifying
the thickness of the turbine blades and making adjustments to the orientation of the turbines... these
modifications have diminished the noise substantially in a number of sites. As for visual appeal, some
creative ways to share the land to create a more attractive wind farm are being piloted.
    So that brings us to the issue of storing wind power. And, although wind energy can be stored temporarily
as battery power, the real challenge for wind power exploration will be how to level out the
energy source. Alternatives for storage will be critical because, even in an area with steady winds, wind
is still not totally reliable. But, the Tellus Institute has released promising results from studies to investigate  Q10
the problem of intermittent wind. This is what they did. By dividing the wind turbines from one farm
into two smaller farms with geographical separation. the capacity of the pair of farms increased by
percent over the efficiency of the larger farm with the same number of turbines. So by taking advantage
of the slightly different wind patterns, a more continuous supply of wind power can be generated.
    So where are we with all of this? Well, the research that will make wind power a viable option is  Q11
underway but We need to continue to study... in Order to solve some of the problems... before we
can use wind Dower as a primary source of energy, globally