When Doug and I think about how we use power on our land and how we will power our house and farm there, we haven’t really considered wind power. It doesn’t suit the site.
But on a national scale, the answer (or 10 to 20 percent of it, anyhow) is blowing in the wind, according to Mitch Brandt, UW-Madison program director of the Department of Engineering Professional Development. He spoke at Wednesday Nite at the Lab.
We’ve come a long way already. In 1995, the entire U.S. was generating only about 1,000 megawatts of wind-generated power. (That’s about what one big coal plant produces.)
Wind power has progressed jerkily because of production tax credits, which Congress has created and then let expire, created and then let expire, making a boom-bust cycle in the early years. In 2005 Congress did a 2-year and then a 3-year extension, which has been extended for one more year. So wind power has finally taken off. In 2010 the newly built capacity dropped because of the economic crash. However, Bradt is hopeful for the future of wind power.
The corridor of our country represented by Minnesota and Montana from the Canadian border to the southern border is a Saudi Arabia of wind. And there are some reasonably usable wind prospects in this part of the Midwest too.
Wind gets clocked for two years at a prospective site, using the same kind of technology that traffic cops clock speeders. If the numbers look good, turbines may go up.
We’ve all seen them. Those tall, 3-blade, upwind turbines revolving at a stately pace that we glimpse as we drive along the interstate. Something that I didn’t realize before is just how big these windmills are. They tend to be 100 meters tall – that’s the height of a 30-story building.
When you look up and see the blades, they are attached to a long compartment which contains the gear box that turns wind into electricity. That compartment is taller than a tall man. They are huge!
Do you ever wonder why the blades seem to be turning so slowly? They are probably spinning around once every three seconds, which looks quite leisurely from down here on the surface of the earth, but the tips of those very long blades are actually hitting 150 to 225 miles per hour. At that rate, a single turbine can generate a 1.5 megawatts of power.
How much power they actually generate depends mostly on the wind speed. Twice the wind means 8 times the power. But you can have too much of a good thing. Some turbines are considered safe up to the power of a Category 3 hurricane, but most have to shut down in wind above 60 mph (gale-force wind).
Many of the newest, cutting edge Type 4 turbines depend on a rare mineral called neodymium, called neo for short. This same material is essential for the motors in hybrid cars and also used to make microphones, professional loudspeakers, in-ear headphones and high performance computer hard discs.
This is problematic, Bradt said, because China is the world’s main supplier of this soft, silvery metal. For a while, China was selling it at a low price. Now China appears to be holding onto their neo, so they can build their own manufacturing industries around it and only sell the value-added final products to the rest of us. This is one of the many issues being currently discussed by Presidents Obama and Hu.
Could get awkward. Perhaps the China issue will create a strategic, lucrative opportunity to those that have a diversity of product offerings.
Nonetheless, Bradt concluded that wind is a great source of energy in windy places. As with many renewable energy sources, once you invest in the structure, the energy is produced cheaply after that. These big turbines are predicted to last at last 25 years.
That said, he predicts that even if we use all the wind we can, it will only supply 10 to 20% of our national power needs. The problem with wind is that it is prone to wild swings. Sometimes its roaring and sometimes its still, but we like to have steady, regular power there whenever we flick the switch.
Ultimately, there is no magic power bullet that is going to let us go on using power at our present rate. We all need to look hard at our power usage and cut it drastically. And that’s not easy, is it?
I’m going to have to look at everything in my life again. This week I started turning my printer off as soon as I use it. It used to come on with the computer and sit on all day. Just in case I needed it that second, right? That’s small potatoes, though.
What power that you are using today are you willing to part with?
Categories: Eco activism