The Obama administration’s solution for expanding wind power nationwide is to construct taller, more technologically advanced wind turbines that likely will be more difficult and expensive to build.
The Department of Energy used last week’s Windpower 2015 Conference to issue a report that shows how the large turbines can spread the promise of wind energy to all 50 states, with the big target being the Southeast.
Currently, most of the nation’s wind potential resides in the breezy middle of the country, with the Southeast’s geography making it less desirable for developing wind-generated renewable electricity. But that could change by increasing the height and overall size of windmills to capture the strong wind currents that are out of reach for shorter, less advanced turbines.
“This expanded technical potential is primarily in the Southeast United States, with improved deployment potential for wind in the Northeast and throughout the West as well,” says the new Energy Department report “Enabling Wind Power Nationwide.”
The American Wind Energy Association applauded the report as recognition of the nation’s vast wind energy potential. The industry association said scaling up wind from more conventional 80-meter wind towers to bigger 100-130 meter towers would enable states to tap their wind resources, which in the past could not be achieved with the standard towers. A 130-meter tower is about 426 feet, or about 120 feet taller than the Statue of Liberty.
The Energy Department’s National Renewable Energy Laboratory, which is testing to deploy enormous 1 megawatt wind turbines, says the towers could generate electricity in a variety of wind conditions by using features such as blades with pitch control like an airplane, while using their sheer mass to continue rotating even when there is no wind.
Currently, the giant turbine towers, with larger blades and composites, are primarily used in Europe, with relatively few in the United States. Cost is another issue that could present a hurdle for deployment in the near-term.
The Energy Department report points out that the “cost of wind turbine towers increases rapidly with increasing height, creating a trade-off between tower cost and the value of added energy production.”
“Many taller tower concepts are either commercial products or have been demonstrated at full-scale, but are not yet widely deployed in the United States due to unfavorable economics,” the report points out. “Development of advanced manufacturing techniques for taller towers, such as enabling modular assembly or on-site tower production, represents a significant opportunity for the wind industry and its supply chain.”
There are transportation hurdles in moving the giant components necessary to construct a giant 130-meter tower in remote areas where they would likely be built, according to the report. Because the blades for the generators need to be in one piece, and cannot be assembled from smaller components, they are difficult to transport from the manufacturer to the construction site.
A variety of other constraints need to be figured out before the large wind turbines can become a reality in all 50 states.
“In addition to addressing the logistical and transport constraints of larger blades, towers and drivetrains, [other] wind system design considerations are needed,” according to the Energy Department report. The bigger turbines would need more advanced aerodynamic controls, rotor control systems and even new cranes to construct the behemoths.
There are also wildlife considerations, including the “interaction” between the larger turbines and bats, bald eagles and other birds. In the past, the government has allowed for a limited number of eagle kills for wind projects per year, but understanding migration cycles and other issues with species in the Southeast will take more study to understand the effects, the report says.
“More bird species could potentially be affected as wind moves into new areas, and increasing rotor heights may increase the potential for interaction between birds and turbines,” the report says. “One issue in particular is the difference in interactions between golden eagles and wind turbines, of which there is significant experience — and the interaction of bald eagles with wind turbines, of which there is little or no experience.”
The wind study was issued on the same day the American Bird Conservancy highlighted new research showing how wind turbines are encroaching on bird habitats and threatening many species. An official with the group says the idea of building even larger turbines is very concerning. The director of the group’s smart wind campaign, Michael Hutchins, said in a press release that the research underscores the need for new mandatory permitting requirements for the wind industry that take into account bird migrations in siting wind farms.
Considering these hurdles, other companies are touting new alternatives to conventional wind turbines.
One company that says it has the answer has a “radical” proposal. It says the future of wind towers is to go “bladeless.” The company, Vortex Bladeless, says it can build a comparable 1 megawatt wind generator at apparently half the cost of its conventional counterparts. The Vortex turbine uses wind currents to vibrate a large cylinder that oscillates to create electricity.
An official with the company says Vortex has received positive feedback from engineers with conventional wind companies. “They understand the concept, it works, and now we are focusing on optimizing the technology to make the first commercial product,” said Yana Gorbolsky, the company’s outreach director.
The idea has been drawing a lot of media attention in recent weeks as the future of wind energy. So much attention in fact, that it appears to be making the company some enemies.
In an anonymous article published by the website CleanTechnica.com, the unnamed “guest contributor” takes aim at the company’s business model and engineering.
“The Vortex Bladeless wind turbine recently covered here on CleanTechnica and many other sites is, unfortunately, yet another example of an impractical, uncompetitive wind turbine that is getting too much hype for its extremely weak results and potential,” the article reads.
Forbes and Wired magazines have featured the company prominently as the new darling of the energy and technology world. But the CleanTechnica article goes through a list of criticisms, bashing its low-cost projections.
“The claims that they make … of [their product being] 50 percent cheaper to build are based on a small prototype with no experience in manufacturing. Similar claims are made by every wind innovator, but it’s never proven true before. Serious skepticism is required,” the article reads.
Beyond the media attention, the company has been touted by environmentalists for developing an alternative that does not interfere with bird migrations, does not kill eagles and generates no noise.
