Wind turbines continue to be the most controversial so-called “renewable” energy source worldwide. Yet, you say, wind is surely renewable. Really? Sure, the wind blows intermittently, but what if wind power actually contributes to global warming?
While the wind itself may be “renewable,” the turbines surely are not. Arcadia Power reports that the widely used GE 1.5-megawatt (MW) turbine, is a 164-ton monster with 116-foot blades on a 212-foot tower that weighs another 71 tons. The Vestas V90, which has 148-foot blades on a 262-foot tower, has a total weight of about 267 tons. That is just ONE TURBINE!
How are these giants constructed? The U.S. Geological Survey, citing the National Renewable Energy Laboratory, states that turbines are predominantly made of steel (which comprises 71 to 79 percent of total turbine mass), fiberglass, resin, or plastic (11 to 16 percent), iron or cast iron (5 to 17 percent), copper (1 percent), and aluminum (0 to 2 percent). On top of that, one Canadian company admits it uses over 800 metric tons of concrete for each turbine it places in the ground.
Recycling these materials (not the fiberglass and plastic in the blades) also consumes considerable energy – on top of the energy and environmental disturbances required to mine, process, and ship these materials to the turbine factories. Often, highways and city streets are shut down during transport to wind farm sites often hundreds, even thousands, of miles away.
Wind Power Monthly admits that “wind turbine transportation logistics can be a deciding factor in scheduling and costing a project. The challenge of moving equipment from ports and factories to wind plant sites has only become more formidable as the industry has shifted to larger, multi-megawatt turbines.
Back in 2010, transportation costs totaled an average 10 percent of the upfront capital cost of a wind project. Transporting the nacelles (that house the energy-generating components, including the shaft, generator, and gearing, and to which the rotor and blades are attached) typically required a 19-axle truck and trailer that cannot operate using renewable energy and which a decade ago cost about $1.5 million apiece.
Transmission lines also add to the cost, and use of non-renewable materials. To get wind-generated energy from largely remote locations to cities eager to cash in on the 2.3 cent per kilowatt-hour production tax credit, the U.S. is constructing $47.9 billion on transmission lines through 2025, of which $22.1 billion will be spent on transmission projects aimed at integrating renewable energy into the existing power grid.
On top of all that, wind turbines only last maybe 20 years – then they have to be decommissioned (taken down). According to Isaac Orr, a policy fellow at the Center of the American Experiment, the cost of decommissioning a single turbine can reach half a million dollars – and the huge, largely fiberglass blades cannot be recycled.
All of these activities – mining and processing the iron ore and other metals that go into turbine manufacturing, transporting the huge beasts to the sites, and decommissioning them are all energy intensive activities that generally rely on fossil fuels and leave difficult to dispose of wastes behind.
So, while some are reporting that the costs for wind energy delivery (per kilowatt-hour) are becoming competitive (but if so, then why do the subsidies remain?), wind energy is hardly “renewable” or at least hardly Earth-friendly.
Thus, it was not surprising to find a new study by postdoctoral researcher Lee Miller and his Harvard colleague, David Keith, professor of applied physics and public policy, which found that heavy reliance on wind energy will increase climate warming. The authors raise serious questions about just how much the U.S. or other nations should rely on wind power.
The warming is produced, the authors noted, because wind turbines generate electricity by extracting energy out of the air, slowing down wind and otherwise altering “the exchange of heat, moisture, and momentum between the surface and the atmosphere.” The impact of wind on warming in the studied scenario was 10 times greater than the climate effect from solar farms, which can also have a warming impact, the scientists said.
The study, published in the journal Joule, found that if wind power supplied all U.S. electricity demands, it would warm the surface of the continental United States by 0.24 ˚C – far more than any reduction in warming achieved by decarbonizing the nation’s electricity sector (around 0.1 ˚C) during the 21st Century.
“If your perspective is the next 10 years, wind power actually has – in some respects – more climate impact than coal or gas,” says Keith, a huge wind power supporter. But, he added, “If your perspective is the next thousand years, then wind power is enormously cleaner than coal or gas.” However, his analysis assumes a significant warming that has yet to occur despite increasing use of fossil fuels.
Maybe, my friends, the answer is NOT blowing in the wind.