Fort Worth energy firm prepares first turbine prototype
EditorÂ’s Note: This is the second in a series of articles exploring startup company SkyDrill Power Systems.
SkyDrill Power Systems LLC is moving closer toward its goal of emerging as a big player in the stateÂ’s growing alternative energy business by keeping its eggs in many baskets, as the expression goes.
The 16-month-old company will pour the foundation in about two weeks for a vertical-axis wind turbine at West Texas A&M University to use for real-world testing and data gathering. The turbine, SkyDrillÂ’s first prototype, is expected to be up and running by the end of February.
Vertical-axis wind turbines, or VAWTs for short, are the first project CEO Barry Sterling and company are exploring, with many more in various stages of developments from simple “what-if” ideas to funding requests for the go-ahead – horizontal-axis wind turbines, solar panels, energy consulting and more.
The VAWT system was the genesis for SterlingÂ’s desire to create a company that could offer a host of alternative energy solutions to customers and clients across the state and nation.
“It goes back to starting out our company and we were trying to come up with an efficient system that could be used in urban areas, because when most people think about wind energy they think about the large horizontal-axis wind turbines out in West Texas,” said Sterling, 32, also founder and president. “We really were attempting to find something that would be both aesthetically pleasing and functional – something that you can look out my window and see some of these things on tops of roofs.”
While horizontal-axis wind turbines resemble a propeller of an airplane or ship, a vertical-axis wind turbine acts something more like a coin spinning on its side, though the turbine panel itself isnÂ’t circular.
“It is exactly the same principle as a horizontal-axis wind turbine and all the same physics apply in how you derive energy from the wind,” said Patrick Nolan, SkyDrill’s vice president of administration and chief of staff. “The largest difference is it rotates on a vertical shaft rather than a horizontal axis.”
The current SkyDrill design under construction is about half as wide as a typical full-size billboard that sits on top of a monopole tower, Nolan said. The tower height will vary depending on two things: local regulations and what the wind profile looks like.
The forthcoming prototype should be about 100 feet from base to turbine top. The turbine will undergo between six months and 12 months of testing to determine its efficiency, but may be up longer to discover whether internal modifications could improve efficiency, he said.
It all sounds great, but turbine manufacturers canÂ’t escape one fact: BetzÂ’ Law, a 1919 theory developed by German physicist Albert Betz that says, under perfect circumstances, the maximum amount of efficiency that can be achieved by a turbine is 59.3 percent.
“Not all of the energy present in a stream of moving air can be extracted; some air must remain in motion after extraction. Otherwise, no new, more energetic air can enter the device,” according to the U.S Department of Energy’s “20 Percent Wind Energy by 2030” report, released May 2008.
“You can never extract 100 percent of the energy available in the wind, it’s impossible,” Sterling said. “You can only extract a maximum of 59 percent of energy available. So you’re starting at 59 percent … Most horizontal-axis wind turbines are around 40 or 45 percent, so they’re less than that 59 percent.”
Through testing and re-testing, Sterling said SkyDrill engineers determined conclusively that VAWTs arenÂ’t as efficient as HAWT system, but that doesnÂ’t mean they donÂ’t have a place in society.
“There is a use and there is a need for something that’s cost-effective and can be put in urban areas, that maybe has some dual-use,” he said
Nolan agrees, and said city ordinances are making VAWTs more of a necessity for people or companies wanting to harness wind power.
“You really are having most cities saying we do not want a horizontal-axis wind turbine or would not allow a horizontal-axis wind turbine inside the city, the largest reasons are noise and aesthetics,” said Nolan, adding some horizontal-axis wind turbines can be as loud as helicopters when standing nearby. “When you have that but people want a renewable energy source, if they don’t take advantage of the wind or can’t take advantage of the wind, then they’re stuck with solar, or geothermal if that’s possible … The market wants to be wider than that. It wants to be wider than just solar or building efficiencies.”
ThatÂ’s where the VAWT systems come in.
The vision and team are in place, the desire to work is there. Now all Sterling and company have to do is make it work, as a company and as an investment for financier Holt Hickman, the longtime Fort Worth entrepreneur and chief executive of Hickman Cos.
“It’s all about being able to diversify,” Sterling said, “and also identifying how that diversification will affect our bottom-line and how much money it’s going to cost us.”
