Recently, there have been stories purporting to promote “renewable” energy sources on Saipan and to give a (false) sense of hope to the residents of the CNMI that a 150 megawatt “wind farm” would be the panacea that solves all problems now and for the future with visions of cheap, clean and abundant electricity for all.
Well, take a look at the “vision” pictured here. Doesn’t that look a little like Mt. Tapochau? Well, it’s not, and it’s not a doctored picture either; it is a recent picture of the Tehachapi Pass (one of the windiest spots in North America) wind farm in California. It was built several years ago during the “boom” in wind production throughout the world and the U.S. Pictured are 102 towers, about the same number that would be required for the proposed 150 megawatt farm on Saipan. As of the beginning of 2007, nearly 90 percent of them have been shut down due to expense of operation and lack of a real contribution to the California grid system.
“Wind power promises a clean and free source of electricity. It will reduce our dependence on imported fossil fuels and reduce the output of greenhouse gasses and other pollution.” This quote is taken from proponents of wind power at the national level. But is it accurate? A little research reveals that wind power does not in fact live up to the claims made by its advocates, that its impact on the environment and people’s lives is far from benign, and that, with such a poor record and prospect, the money spent on it could be much more effectively directed.
Denmark has over 6,000 turbines that produced electricity equal to 19 percent of what the country used in 2002. Yet no conventional power plant has been shut down. Because of the intermittency and variability of wind, conventional power plants must be kept running at full capacity to meet the actual demand for electricity. Denmark is just dependent enough on wind power that when the wind is not blowing just right they must import electricity. Danish electricity costs for the consumer are the highest in Europe.
The head of Xcel Energy in the U.S., Wayne Brunetti, said, “We’re a big supporter of wind, but at a time when the customers have the greatest needs, it’s typically not available.” Throughout Europe, wind turbines produced on average less than 20 percent of their theoretical (or rated) capacity. The figure in Denmark was 19 percent in 2003. Onshore turbines in the U.K. produced at 24.1 percent of their capacity in 2003. In Germany it was 14.7 percent. In the U.S., usable output (representing wind power’s contribution to consumption, according to the Energy Information Agency) in 2002 was 12.7 percent of each turbines capacity. The rated generating capacity only occurs during 100 percent ideal conditions, typically a sustained wind speed of over 30 mph. As the wind slows, electrical output falls exponentially as the cube of wind speed. At one half the rated wind speed, energy output falls to only 1/8 output capacity.
In high winds (over 80 mph), the turbines must be stopped because they are easily damaged. Build-up of dead bugs (on the blades) has been shown to halve the maximum power generated by a wind turbine, reducing the average power generated by 25 percent or more.
Despite their being cited as the shining example of what can be accomplished with wind power, the Danish government has cancelled plans for three more offshore wind farms planned for 2008 and has scheduled the withdrawal of subsidies from existing sites. Spain began withdrawing subsidies in 2002. Germany reduced tax breaks to wind power in 2004. Switzerland is cutting subsidies as too expensive for the lack of any significant benefit. The Netherlands decommissioned 90 turbines in 2004. Many Japanese utilities now severely limit the amount of wind generated power they buy because of the instability they cause. In 2003, Ireland halted all new wind power connections to the grid. In 2006, the Spanish government ended, by emergency decree, its subsidies and price supports for big wind. In 2004, Australia reduced the level of renewable energy that utilities are required to buy. On Aug. 31, 2004, Bloomberg News reported that “the unstable flow of wind power in their networks” has forced German utilities to buy more expensive energy, requiring them to raise prices to the consumer. In the U.K., the Telegraph has reported that rather than providing cheaper energy, wind power costs the electric companies _50 per megawatt-hour, compared to _15 for conventional power.
Christopher Dutton, the CEO of Green Mountain Power, a partner in the Searsburg wind farm in Vermont and an advocate of alternative energy sources, has said that there is no way that wind power can replace more traditional sources; that its value is only as a supplemental source that has no impact on the base load supply. “By its very nature, it’s unreliable,” says Jay Morrison, senior regulatory counsel for the National Rural Electric Cooperative Association.
Pictures from the energy companies show slim towers rising cleanly from the landscape or hovering faintly in the distant haze, their presence modulated by soft clouds behind them. But a 200- to 300-foot tower supporting a turbine housing the size of a bus and three 100- to 150 foot rotor blades sweeping over an acre of air at more than 100 mph requires, for a start, a large and solid foundation (more than 25,000 pounds of reinforced steel and up to 3,500 cubic yards of cement). On a GE 1.5-MW tower (pictured at right), the turbine housing, or nacelle, weighs over 56 TONS, the blade assembly weighs over 36 TONS, and the whole tower assembly totals over 163 TONS. (Yes, those are real people up there!)
Florida Power & Light (FPL Energy) says, “Although construction is temporary (a few months), it will require heavy equipment, including bulldozers, graders, trenching machines, concrete trucks, flatbed trucks, and large cranes.” Getting all the equipment, as well as the huge tower sections and rotor blades, into an undeveloped area requires the construction of wide, straight and strong roads. The destructive impact that such construction would have, for example, on a wild mountain top, is obvious. Erosion, disruption of water flow, and destruction of wild habitat and plant life would continue with the presence of access roads, power lines, transformers, and the tower sites themselves. For better wind efficiency, each tower requires trees to be cleared. Vegetation would be kept down with herbicides, further poisoning the soil and water. Each tower would be at least 5 to 10 times the rotor diameter from neighboring towers and trees for optimal performance. For a tower with 35 meter rotors, that is 1200 to 2400 feet, a quarter to a half a MILE. A site on a forested ridge would require clearing 45 to 90 acres per tower to operate optimally. FPL says it requires 40 acres per installed megawatt, and the U.S. EPA says 60 acres is more likely.
GE boasts that the span of their rotor blades is larger than the wingspan of a Boeing 747 jumbo jet. The typical 1.5 megawatt assembly is two stories higher than the statue of liberty. Wind power stations are not “parks.” They are industrial and commercial installations.. Many people are drawn to wild places to avoid such reminders of human industrial might. Many communities depend on such tourists, who will now seek some other, as yet unspoiled, retreat.
On Saipan, a 150 megawatt facility would require 100 towers with a typical 1.5 megawatt generator on top. This would cover an area of nearly 6000 acres. If spaced appropriately and in 4 parallel rows, this would cover a site 5 miles long and 1 _ miles wide (including required setbacks). It would cost between $700 and $800 MILLION dollars to build over a 6 year time period and at the end, by national statistics (from the U. S. Energy Information Agency) would actually deliver about THREE (3) net megawatts to the community!
Wind towers require a large amount of energy to operate. Other electricity plants generally use their own power, and the difference between the amount they generate and the amount delivered to the grid is readily determined. Wind plants, however, use electricity from the grid, which is NOT accounted for by any current manufacturers (Vestas, GE, and NEG Micon) in their output figures. Among turbine functions that USE energy:
-Yaw mechanism control (to keep blades perpendicular to wind and untwist cables)
-Blade pitch control (to keep rotors spinning at a regular rate)
-Lights, controllers, communication, sensors, metering, etc
-Heating, cooling or dehumidifying the nacelle
-Oil heater and pump and cooler in gearbox
-Hydraulic brake (to lock blades in high wind)
-Thyristors to regulate connection and disconnection to the grid
-Magnetizing the stator (up to 10 percent of rated capacity used here)
Using the generator as a motor (to help start blade rotation in low wind – the grid magnetized stator must work to help keep the 40 ton blade assembly spinning, along with the gears that increase the blade rpm some 50 times for the generator, not just at cut-in [15 mph], but at least some of the way up to full rated wind speed [30 mph])
It is estimated that EACH turbine may consume as much energy as it produces (under less than perfect wind conditions) in its own operation. Under these conditions, the plant as a whole, which may produce only 25 percent of its rated capacity annually, would be using nearly all of the electricity it produces unless wind speeds were nearly constant at 30-40 mph at all times.
The spinning blades kill and maim birds and bats. Especially vulnerable are large birds of prey that like to fly in the same sorts of places that developers like to construct wind towers. Guidelines from the U.S. Fish and Wildlife Service (FWS) state that wind towers should not be near wetlands or other known bird or bat concentration areas. A 2002 study in Spain estimated that 11,200 birds of prey (many of them endangered), 350,000 bats, and 3,000,000 small birds are killed each year by wind turbines there. On average a single turbine tower kills 20-40 birds each year.
The wind industry insists that noise is a thing of the past. Indeed, new turbines may have quieter gears and turbines, but the huge magnetized generators can not avoid producing a low frequency hum, and the problem of 100-foot rotor blades chopping through the air at over 100 mph also is insurmountable. A 35 meter blade turning at 20 rpm is moving 164 mph at the tip. Every time each rotor passes the tower, the compression of air produces a deep resonating thump. Such noise has been described (at a distance of 800 to 2000 meters) as “like aircraft continually passing overhead.” “as if someone were mixing cement in the sky,” and “like a train that never arrives.”
The penetrating low frequency aspect to the noise, a thudding vibration much like the throbbing bass of a neighboring disco, travels much farther than the usually measured audible noise. Many people have complained that it causes anxiety and nausea. The National U.S. Wind Coordinating Committee (NWCC) states, “Wind turbines are highly visible structures that are often located in conspicuous settings. they also generate noise that can be disturbing to nearby residents.” The NWCC recommends that wind turbines be installed no closer than a half mile from any dwelling. A German study in 2003 found significant noise levels 1 mile away from a 2 year old wind farm of 18 1.8 MW turbines. A Neighbor of the 20-turbine Meyersdale facility in southwest Pennsylvania measured the noise level at his house, about one half mile away, to average 75 dB(A) over a 48 hour period, well above the level that the EPA says prevents sleep and may lead to sleep disorders.
Energy companies also claim that they increase the local tax base. But that is more than offset by the loss of open land, the loss of tourism, the stagnation or decrease in property values throughout a much wider area, the tax credits such developments typically enjoy, and the taxes and fees consumers must pay to subsidize the industry. Even surveys by wind promoters show that a quarter to a third of visitors would no longer come if wind turbines were installed.
The planners of giant wind turbines in Valencia, Spain, mention the dripping and flinging off of motor oil (almost 200 gallons of which may be present in a single 1.5-MW turbine) and cooling and cleaning fluids. The transformer at the base of each turbine contains up to 500 gallons of oil. The substation transformers where a group of turbines connects to the grid contain over 10,000 gallons of oil each.
The towers are subject to metal fatigue, and the resin blades are easily damaged even by wind. In Wales, Spain, Germany, France, Denmark, Japan, New Zealand, and Scotland, parts and whole blades have torn off by high winds (over 80 mph), malfunction, and fire, flying as far as 8 kilometers and through the window of a home in one case. Whole towers have collapsed in Germany (2002) and the U.S. (Oklahoma, 2005).
On a small scale, where a turbine directly supplies the user and the fluctuating production can be stored or “net-metered” on the base grid, wind can contribute to a home, school or a small factory’s electricity. But this simply does not work on a large scale to supply the grid. Even the small benefits claimed by their promoters are far outstripped by the huge negative impacts.
By Dr. Thomas D. Arkle Jr.
Special to the Saipan Tribune
18 May 2007