Unfortunately, wind doesn’t afford the benefits marketers promise. It isn’t an abundant, reliable power source; doesn’t appreciably reduce fossil dependence or CO2 emissions; isn’t free, or even cheap; doesn’t produce net job gains; nor does it cool brows of feverish environmental critics.
Many green energy advocates have exaggerated the capacity of wind power to make a significant impact on U.S. electrical needs. Any euphoric fantasy that an unlimited, free and clean alternative to carbon-cursed fossil-fuel sources is blowing by with scant notice is exceedingly naïve and misguided.
A major point of public confusion in this regard lies in a failure to differentiate maximum total capacities, typically presented in megawatts (MW), with actual predicted kilowatt hours (kWh), which are determined by annual average wind conditions at a particular site. Wind is intermittent, and velocities constantly change. It often isn’t available when needed most — such as during hot summer days when demands for air-conditioning are highest.
According to a 2009 Energy Information Agency Report on Electricity Generation, wind power provided only 70 billion kWh of the total U.S. 3,953 kWh supply (1.79% of generated power). Yet in May 2008, the U.S. Department of Energy estimated that it is feasible to increase wind capacity to supply 20% of this nation’s electricity and enough to displace 50 % of natural gas consumption and 18% of coal use by 2030.
The report, drawn up by its national laboratories said that meeting this target presumed some important assumptions. It would require improvements in turbine technology, cost reductions, new transmission lines and a five-fold increase in the pace of wind turbine installations. What exactly does that mean in terms of real, available kWh generating output? Actually, it means very little if merely a minor percentage of that technical feasibility provides electricity when needed.
To be extremely optimistic, let’s assume that actual average output would be 25% of that projected installed capacity. In that case, the real output would be less than 5% of the country’s electricity, and more realistically, about half of even that amount under optimistic circumstances.
Output volatility due to wind’s intermittency varies greatly according to location and time of year, typically ranging from 0% to about 50%. Texas, one of the most promising wind energy states, averages about 16.8% of installed capacity, yet the Electric Reliability Council of Texas assigns a value of 10% due to unpredictability. Only about 20% of that capacity is generally available during peak demand periods (about 5:00pm), while average generation during off-peak time averages about 40% of capacity.
Electricity must be instantaneously available day and night to meet “base load” requirements. When peak loads exceed supplies bad things quickly happen. Electrical frequencies and voltages drop as power line currents increase, necessitating automatic or manual interruption of loads (blackouts) to protect grids.
But unlike such workhorse power generators as coal-fired and nuclear plants designed to constantly run at peak load capacities, wind (and solar) power requires incorporation of “spinning reserve” backup systems to provide continuity. These are typically gas-fired turbines, much like those used for jet aircraft engines that are connected to generators. That’s where it gets particularly expensive.
Wind power must be integrated as part of a larger, balanced, grid network. When that wind generation component increases, the temperatures of fossil-fueled boilers must be dropped to maintain demand-supply equality. This involves wasteful shedding of heat for cooling — then more wasting to add heat back into the system without accomplishing any additional work. And since the spinning reserves don’t stop consuming fuel when wind generation is occurring, claims of energy savings or CO2 emission reductions are largely mythological.
But assuming that wind is always blowing somewhere, won’t “smart grids” balance it all out? That is good in theory only. Ed Hiserodt, writing in an October 2010 New American .com. article titled “Wind Power: An Ill Wind Blowing” cites an example of 18 interconnected wind farms located in Southeast Australia. Covering a large area of approximately 40,000 square miles, those installations benefited from sites near a coast where winds are stronger and more constant than inland placements. Yet their combined total capacity was still insufficient to even begin to keep pace with base load demands.
Another major limitation of individual wind farms is that they don’t produce power on massive scales needed in large cities and industrial areas where necessary space is at a premium and land is expensive. The most ideal locations are typically remote from areas where demands are highest, requiring large investments for power transmission lines and land right-of-way use.
Wind turbines are also very expensive to build and maintain. The National Renewable Energy Laboratory reports that “Despite reasonable adherence to those accepted design practices, wind turbines have yet to achieve their design life of 20 years, with most requiring significant repair before the intended life is reached”. Those in offshore locations are even more costly to install, and fare much worse from corrosion damage.
Will the construction and maintenance of wind power produce the many thousands of “high-quality green jobs” touted by the industry? Not according to a report from Spain released by researchers at King Juan Carlos University. It concluded that every “green job” created by the wind industry killed off 4.2 jobs elsewhere in the Spanish economy through missed opportunities to put that money towards more useful and productive ends.
While research director Gabriel Calzada Alvarez didn’t fundamentally object to wind power, he did find that when a government artificially props up the industry with subsidies, higher electrical costs (31%) and tax hikes (5%), along with government debt follow. Each of those jobs was estimated to cost $800,000 per year to create, and 90% of those were temporary. A few months after the study was released, researchers at the Danish Center for Politiske Studier reached similar conclusions based upon their country’s experience: “It is fair to assess that no wind energy would exist if it had to compete on market terms.”
Just how environmentally friendly is that “green” wind energy? Depends a lot on whom you ask and where they live. The best energy-generation sites are typically along mountain ridges and coastal areas–the same types of locations prized for scenic views and overflown by bird and bat species that become turbine blade casualties. And while some national environmental organizations such as Greenpeace and the Sierra Club have become staunch wind power advocates in their war against fossils, others who live in proposed wind farm locations have launched strong legal opposition.
Robert F. Kennedy, Jr., nephew of a popular president and prominent lawyer for the Natural Defense Research Council, has fought hard against a proposed 130-turbine offshore “Cape Wind” development in Nantucket Sound. Another uncle, the late Sen. Ted Kennedy, along with Senate colleague and fellow Massachusetts resident John Kerry, didn’t want Cape Wind disturbing his vistas either.
Then there’s the concern about whales. Yes, you read this right! On June 25, 2010, environmental groups filed a suit to block the Nantucket Sound project because it will endanger migratory birds and whales. Are they possibly underestimating whale intelligence?
But what about risks to our economy and the well-being of ratepayers and taxpayers who must cover wind power costs? More than half of all revenues for companies that install and operate the systems come from federal, state and local tax benefits. Some state programs also legislate mandatory renewable portfolio standards that require electric utility companies to purchase designated amounts of energy from wind, solar and bio-fuel providers, typically at premium costs that are passed on to customers.
So long as industry survival depends upon those preferential government-imposed benefits, two things are clear. Wind is certainly not a competitive free market source of energy, or a charity we can continue to afford.
http://blogs.forbes.com/larrybell/2011/03/08/wind-energys-overblown-prospects/
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