Last week at the UW-Madison Weston Lecture Series, I listened to Julie Lundquist, a professor in the Department of Atmospheric and Oceanic Sciences at University of Colorado-Boulder, explain how meteorologists are going to help usher in the age of wind. (More precisely, 20% Wind – there are some serious people seriously shooting at getting 20% of our energy in the U.S. from wind power by 2030. )
We all think we know what wind is. We’ve all had it fly our kites, and perhaps experienced some of its more dramatic and destructive ramifications. But when we set out to harness the wind, we are working with a very complex force. For a nuts and bolts explanation of how we turn wind into energy check out this Dept. of Energy site.
Wind is ultimately a form of solar energy generated by the uneven heating of the atmosphere by the sun, the irregularities of the earth’s surface and the rotation of the earth. Wind flow patterns are further modified by the earth’s terrain, bodies of water, and vegetation. Those turbines we hoist into the clear, blue sky are penetrating a very complex atmosphere.
Wind energy production in the U.S. has doubled in the past few years, Lundquist said. But making wind a serious part of our energy portfolio is complicated because both wind energy and our power needs fluctuate constantly. Meteorologists can help balance that fluctuation by predicting very accurately how much energy is going to be generated by wind turbines at a given location and a given point in time.
There is a lot of fine tuning that can be done on current wind turbine design. Existing wind turbine specifications were quickly developed, often using wind profile data that does not reflect the subtle reality of wind. But meteorologists are constantly improving our understanding of what the wind is capable of doing. They now use something like a police radar gun shot straight up into the air, and what they are finding is that there are times, especially in evening as the surface of the earth cools, that can kick up winds exceeding turbine design specifications. Applying the results from these monitoring tools can make a 20% difference in efficiency.
Wind direction also fluctuates with height. As we make turbines larger and larger, this is going to be a significant challenge that requires precise and accurate data.
Dr. Lundquist also noted that a lot of wind farms out there have been spinning for about 20 years – which is their expected life span. It’s time to take a very close look at how to build the next generation of turbines. “Our wind farms are not as efficient as they could be,” Lundquist said. Most of them were not sited using the kind of meteorological info that’s out there now. Nor are they built with the current level of engineering knowledge. The industrial standard, the 3-blade turbines that we see everywhere, are simply the best compromise in non-turbulent conditions. That may be about to change.
Current research is not only are looking at how to make the turbines more efficient. Meteorologists are studying how planting a forest of turbines affects the ground below it, in front of it and behind it.
The 20% Wind Scenario is not likely to be realized in a business-as-usual future. Achieving this scenario means a major national commitment to clean, domestic energy sources. The future of wind power is as uncertain right now as the weather outside my window.
And that ambiguity may increase. “There is a lot of uncertainty about how climate change will drive future wind projects,” Lundquist said as she finished. The implication is that we may be looking at a lot more wind in some areas, but there can be too much of a good thing from the perspective of a machine the size of a bus on top of a stick taller than a football field.
We are going to need our meteorologists and engineers more than ever!
How is wind power affecting your life so far? Do you get some wind power from your energy provider? Do you have a wind farm in your neighborhood? Do you pay a premium to your utility provider to support more green energy?