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EcoIQ Magazine Spring 2002 Features

2001 article at EcoIQ

Tags: lester brown, power, wind on 2007-12-29 -All Annotations (0) -About

more fromwww.ecoiq.com

reliminary
data show world wind electric generating capacity climbing from 17,800
megawatts in 2000 to an estimated 23,300 megawatts in 2001 - a dramatic
one-year gain of 5,500 megawatts or 31 percent. As generating costs
continue to fall and as public concern about climate change escalates,
the world is fast turning to wind for its electricity.
One megawatt of wind-generating capacity typically will
satisfy the electricity needs of 350 households in an industrial society,
or roughly 1,000 people. Thus, the 23,300 megawatts of generating capacity
now in place is sufficient to meet the residential electricity needs
of some 23 million people--equal to the combined population of Denmark,
Finland, Norway, and Sweden.
In the United States, there is enough harnessable
wind energy in just 3 of the 50 states - North Dakota, Kansas, and Texas
- to satisfy the country's electricity needs. And China can easily double
its current electricity generation from wind alone.
Low-cost electricity from wind brings the option of electrolyzing
water to produce hydrogen, which can easily be stored and used to fuel
gas-fired turbines in backup power plants when wind power ebbs. Over
time, hydrogen produced with wind-generated electricity is the leading
candidate to replace natural gas in gas-fired power plants as gas reserves
are depleted.

Hydrogen is also the ideal fuel for the fuel cell engines
that every major automobile manufacturer is now working on. Honda and
DaimlerChrysler both plan to have fuel cell-powered vehicles on the
market in 2003.

Wind power offers long-term price stability and energy
independence. Not only are costs low and falling, but with wind-generated
electricity there are no abrupt price hikes, as with natural gas. There
is no OPEC for wind, because wind is widely dispersed. An inexhaustible
source of energy, wind offers us more energy than we can use, and it
does not disrupt climate.

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WorldChanging: Tools, Models and Ideas for Building a Bright Green Future: It's a Bird, It's a Plane, It's Airborne Wind Power

Tags: alternative, energy, wind on 2007-12-28 and saved by2 people -All Annotations (0) -About

in list: Sustainable Futures

more fromwww.worldchanging.com

1% of the jetstream's wind power could supply all US electrical demand. Also, one of the main complaints about wind power is its intermittency--the wind doesn't blow all the time, and so (according to Sky Windpower), most wind farms are only operating at their peak capacity 19-35% of the time. The wind is much steadier at altitude, so you get even more advantage over ground-based wind power. A final advantage is ad-hoc generation: devices with a reasonably simple tether-system do not have to be permanently installed in one place, they could be trucked out to any location that needed them.
biggest lightning rod you've ever seen.
The obvious question is safety. What happens if one of these things falls out of the sky? The proposed design has quadruple-redundancy in the propellers used to hold it up and generate power, and the units could be located away from population centers, so that seems reasonable. What about planes running into them, or more likely, their tethers? They would fly in restricted airspace. Sky Windpower points out that there are already many high-altitude tethered balloons in the US that have not had problems, and that enough installations to generate 100% of the US's power needs could fit in 1/400th of the nation's airspace. What about birds getting killed? They say that the flying windmills could make noise that would keep birds away; this would be prohibitive for ground-based turbines, but at high altitude no people will be around to be annoyed by it.

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Production Tax Credit for Renewable Energy

Tags: tax, wind on 2007-12-26 and saved by2 people -All Annotations (0) -About

in list: Sustainable Futures

more fromwww.ucsusa.org

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How Wind Energy Works

Tags: global warming, wind on 2007-12-26 and saved by2 people -All Annotations (0) -About

more fromwww.ucsusa.org

Wind energy is the fastest growing source of electricity in the world. Global installations in 2005 reached more than 11,500 megawatts (MW)–a 40.5 percent increase in annual additions compared with 2004–representing $14 billion in new investments. [1] In the United States, a record 2,431 MW of wind power was installed in 2005, capable of producing enough electricity to power 650,000 typical homes.[2] Despite this rapid growth, wind power is still a relatively small part of our electricity supply–generating less than one percent of both the and global electricity mix. But thanks to its many benefits, and significantly reduced costs, wind power is poised to play a major role as we move toward a sustainable energy future.
The modern wind era began in California in the 1980s. Between 1981 and 1986, small companies and entrepreneurs installed 15,000 medium-sized turbines, providing enough power for every resident of San Francisco. Pushed by the high cost of fossil fuels, a moratorium on nuclear power, and concern about environmental degradation, the state provided tax incentives to promote wind power. These, combined with federal tax incentives, helped the wind industry take off. After the tax credits expired in 1985, wind power continued to grow, although more slowly. Perhaps more important in slowing wind power's growth was the decline in fossil fuel prices that occurred in the mid-1980s.
Denmark, for example, already meets about 20 percent of its electricity demand from wind power.[3] Wind generation also accounts for about six percent of the national power needs in Spain, and five percent in Germany.[4] Serious commitments to reducing global warming emissions, local development, and the determination to avoid fuel imports have been the primary drivers of wind power development in
The wind resource–how fast it blows, how often, and when–plays a significant role in its power generation cost. The power output from a wind turbine rises as a cube of wind speed. In other words, if wind speed doubles, the power output increases eight times. Therefore, higher-speed winds are more easily and inexpensively captured.
Combined, these resource assessments have found that the windy areas (class three and above) in the United States–if fully developed–could supply more than four times the nation's current electricity needs.
The term used to describe this is "capacity factor," which is simply the amount of power a turbine actually produces over a period of time divided by the amount of power it could have produced if it had run at its full rated capacity over that time period.

A more precise measurement of output is the "specific yield." This measures the annual energy output per square meter of area swept by the turbine blades as they rotate.
Large wind turbines, most often used by utilities to provide power to a grid, range from 250 kilowatts up to the enormous 3.5 to 5 MW machines that are being used offshore. Today, the average land-based wind turbines have a capacity of 1.5 MW.[7] Large turbines sit on towers that can be anywhere from 50 to 100 meters tall, and have blades that range from 30 to 50 meters long.[8] Utility-scale turbines are usually placed in groups or rows to take advantage of prime windy spots. Wind "farms" like these can consist of a few or hundreds of turbines, providing enough power for tens of thousands of homes.
As wind power costs become more competitive, demand is growing exponentially all over the world. Global wind power capacity rose from just over 6,000 MW in 1996 to more than 59,000 MW by the end of 2005–almost a ten-fold increase.[9] Growth has recently been most significant in
Northern Europe
,
Spain
, and
India
, but markets in
Asia
and the Pacific region are emerging as well.
State-level renewable electricity standards–a requirement placed on electric utilities to gradually increase their use of renewable energy sources over time–are also working as a primary driver of
U.S.
wind development. Nearly half of all wind power capacity built from 2001-2005 was attributable to state standards, according to the DOE’s Lawrence Berkeley National Laboratory

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Cats, not windmills, bigger threat to birds / Bats more at risk, says impact study on wind power

Tags: cats, wind on 2007-05-06 -All Annotations (0) -About

more fromwww.sfgate.com

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