We were just talking about GE’s new taller wind turbine tower, which will hit the market next week at a whopping 139 meters, when along comes the latest American Wind Energy Association wind power report showing that the great state of Iowa now gets about 27 percent of its electricity from wind. With the tallest turbine in Iowa reaching only 94 meters, imagine what’s going to happen to Iowa wind power production when taller wind turbine towers get into the ground.
Now, here’s where it gets interesting. We had a great sneak peek at GE’s new taller wind turbine tower earlier this week, and while we were talking with the folks over there the subject of taller wind turbine towers made with concrete came up. It just so happens Iowa is home to at least two of the larger cement plants in the US (concrete is cement mixed with an aggregate), so let’s take a quick look back at what we learned from GE in terms of materials and the cost of wind power.
Low Cost Wind Power And Taller Wind Turbine Towers
Our visit to GE took us to the Mohave desert, where the company has built a 97-meter prototype (limited to 97 by FAA regulations) for the 139-meter commercial version of its new “Space Frame” steel turbine tower. One key takeaway from our conversation there was the influence of factors on the cost of wind power other than the efficiency of the turbine itself.
In terms of the wind turbine tower, those other factors include raw materials, shipping, and labor, all of which can curtail height to cost-effective dimensions.
Within the shipping costs you also find a whole tangle of complications. One key factor there is the configuration of roads, bridges, and tunnels.
That’s why, GE pointed out to us, you’re not going to see much in the way of tubular-style wind turbine towers with a base larger than the current standard. Right now, the industry is conforming to the size of components that can get from point A to point B on a flatbed hauler, and with the size of the base curtailed, you’re not going to gain much in height from here on out.
That’s where GE’s solution comes in. It’s a steel space frame (that’s an engineering term for latticework) tower and instead of coming in a tube it has five distinct sides that are assembled on site. It can be flatpacked for transit, and the whole thing fits into standard shipping containers.
Another solution already on the market is to build all or part of the tower from concrete, though given the logistics involved with concrete that’s not a one-size-fits-all solution. It could be more cost-effective in regions where a cement plant is handy, and that’s where Iowa comes in.
Iowa And Taller Wind Towers
Iowa has four Portland cement sites, two of which are listed by the US EPA as among the larger cement plants in the country. It makes sense to give the local industry a boost and that is exactly what has been going on.
Just last May we noticed that researchers at Iowa State University are working on stress tests for a concrete wind turbine tower. Though their goal of 100 meters falls short of the GE Space Frame mark, it’s well above the currently typical range of 80 meters. The research has been funded by the state’s Grow Iowa Values economic development fund.
Also with the state’s cement facilities in mind, back in 2011 Spain-based Acciona Windpower announced plans for building concrete wind turbine towers in Iowa. We don’t have an update on that project but the company does have a turbine with a 120-meter concrete tower on the market.
Iowa At 27% Wind Power
Iowa is one of eleven states that are part of MISO, a regional grid operator that is very keen on wind power. Iowa Governor Terry Branstad (R) has also been an aggressive champion for extending the production tax credit for wind power, despite his party’s marked lack of enthusiasm.
Those are two key factors driving the state’s growth in wind power. According to the latest report from the American Wind Energy Association (AWEA), wind power accounted for 27 percent of the total electricity production in the state in 2013.
It looks like we ain’t seen nothing yet. Another key factor in Iowa’s wind energy growth is Warren Buffet, the well known investor. His MidAmerican Energy company is already heavily involved in the Iowa wind industry and just last year he announced that he would pour another $1.9 billion into new wind farms in Iowa.
Note: for the record, we got that figure of 94 meters for Iowa’s tallest wind turbine tower from the Iowa Energy Center at Iowa State (it happens to be a GE project, coincidentally). If you know of a taller one in the state, please let us know in the comment thread.
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