Friday, August 18, 2017

Wind Turbines


Woosh.
First blade chasing second, third
The fox chasing its tail.
Etching an invisible circle.
High above the horizon.
The pedestal tethers it.
Impassive, the blades absorb the wind’s whims.
Ferociously twirling
Or falling to a snail’s pace.

Wind turbines.
Turning wind into electricity.

“Industrial looking,” I think as I peer through the windshield. We are driving east, leaving behind the charmed greenery of the forested Cascade mountains and encountering the dry vistas of eastern Washington, officially called shrub-steppe habitat.

I am surprised by their numbers. After I see one wind turbine, a lone metal structure on the ridge ahead, I notice ten, then many, each lone soldier joining an army of wind turbines, now humbling the desert with their looming presence.

My mind protests their interruption of the sweeping vista, their dominance over the scrubby hills. The wind turbines contradict my experience of the emptiness of this region, most commonly used as open range for livestock.

Lynne and I are driving through barren land. Few signs of human habitation rise from the arid soil, spotted with parched green sagebrush, native grasses and occasional yellow wild flowers bobbing on the end of long stems. The land is punctuated by random rocks.

We turn off  Highway 90 and twist up a series of hills to reach the ridge tops of Whiskey Dick Mountain. This is the location of the Puget Sound Energy’s Wild Horse Wind Farm and Solar Facility (https://pse.com/aboutpse/Facilities/Pages/Wild-Horse.aspx). We’re hoping to be in time for the Sunday afternoon 2 o’clock tour.  When we finally arrive, and I eagerly step out of the car, the wind whips my hair and flaps my sweater. I hurry up to the shelter of the Visitor’s Center. We sign up for the tour and pick up our required protective helmets and glasses.

Our young guide, Bilal, is slightly bearded with a friendly face, framed by the hard hat that he wore at a jaunty angle. His uniform jacket is buttoned casually to show off the kerchief around his neck. I tag him as a Millennial, following the rules but interpreting them with a fashionable flare. He wears steel toe boots that add seriousness to his casual stance. I like listening to all the facts he tells us, absorbing some and letting some pass me by. Bilal is willing and able to answer the many technical questions brought up by the group of twenty earnest tourists, who, amazingly, have chosen to come to the Wind Farm on Mother’s Day.

We are touring a wind farm strategically placed to take advantage of the weather conditions at this location on the east side of the Cascade mountains.  The wind blows hard here when the sun warms the land and the air hot air rises. Cool air rushing over through Stampede Pass from the west side of the mountains contributes a steady supply of wind in the spring and summer months.

As our guide speaks, I recognize the necessary ingredients that are here: an area with sparse human population, unproductive land, lots of predictable wind, and demand for electricity within a viable distance, in this case, Ellensburg. He shares the technical details of the 10,800 acre wind farm, using terms like turbine (converts wind energy to rotary motion), “nacelle” (the part that the blades attach to), and “yaw” (the blades turn to face the wind at the best angle).

“How long does each wind turbine last?” a middle aged man asks, his wife attentive to the answer.

“Twenty to thirty years,” Bilal says. “They take about ten to eleven years to pay themselves off.”

One blade is on display on the ground outside the Visitor Center. The opening at the biggest end is more than twice as high as I am. The blade twists and tapers down to less than 2 feet across 129 feet later. It weighs seven tons.

Each blade is carefully matched to the two other blades for the turbine, he explains.
“When one blade is compromised they must set aside the other two and wait for a replacement  to be made that matches the others. They must all be within 8 pounds of each other.”

Each turbine costs close to three million dollars. The entire project at Wild Horse Wind Farm costs $478 million. It produces energy to supply electricity for up to 70,000 homes per year.

He leads us down the path towards the base of one of the 149 wind turbines manufactured by Vestas. From the highway, they seemed quiet, but up close, away from the obscuring sound of cars on pavement, I can hear the blades passing by in a regular rhythm, close to where I stand.

I don’t mind the sound—it is more pleasing than other sounds in my urban life: the sound of our neighbors’ air conditioning, vehicle traffic on I-5, train whistles in the middle of the night, or border patrol helicopters flying over my house. Each passing blade evokes an awareness of the energy flying by in the wind. Still, the guide tells us that people don’t like to live closer than 1000 feet to a wind turbine because of the constant noise. The flickering shadow cast by the turning blades are also incompatible with human comfort. They might drive you crazy.

The group follows our guide down a gravel path through carefully transplanted native plants, including hedgehog cactus and balsamroot, to the door at the base of one of the wind turbines.  Bilal unlocks it and invites us inside, where all twenty of us stand in a circle, dwarfed by the open space that disappears 220 feet up at the top of the pedestal. He points out the electrical properties of the smooth inside walls, and we peer down at the base anchored 30 feet into the soil.

The adaptability of each turbine, he explains, comes from a computer that measures the wind direction and swivels the blades to face the direction of the wind. It also twists the blades to increase or mollify the power of the wind. Under some conditions, the blades must be held back from turning.  They consume energy when they are not turning.

When we are done inside, we step out to stand amidst the field of turbines.

I bring up the subject of bird deaths. Bilal deftly defends wind turbines. “Wind turbines kill 2.5 birds per year. Newer turbines have been re-engineered to make them more obvious and avoidable to birds,” he says.

He quotes us these statistics:

Number one killer of birds in the United States is buildings.
Number two killer of birds in the United States is domestic cats.
A distant third: Wind turbines.

Hmmm. Lynne and I find two or three dead birds on our patio each year. The glass panels on our patio plus our picture windows kill about the same number of birds each year as one wind turbine.

I steal a moment alone, lingering on the return path, letting everyone else pass me, hoping to record the sound of a wind turbine alone, up close. I am near one tower, resting my eyes on the spread of wind turbines on this ridge.

They seem different now. I feel a fondness for this tribe of tireless towering giants, the beauty of the sweeping blades, the changing pattern made by the different speeds of  turning blades and each one’s fastidious orientation. I feel respect for the investment of engineering talent and hard work that brought this wind farm to production.  I see the challenges of this design, a response to human’s demand for energy, yet I also feel its beauty.



Thanks for Bilal M. Abubakar at PSE’s Wild Horse Wind and Solar Facility for providing expertise for this article.

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