NASA’s Mark Moore is developing methods the government can use to fairly evaluate competing ideas on tethering a turbine-vehicle flying and how to capture and use the wind aloft energy efficiently. Moore’s “turf” starts at about 2,000 feet and runs to over 30,000 feet or just over 500 meters to beyond 9,000.
Moore is an aerospace engineer, centering his focus on advance concepts in the Systems Analysis Branch at NASA’s Langley Research Center. Now he’s set with a $100,000 grant from the federal government to research what it will take to judge the value of tethered winds aloft energy generators. This is the guy who is setting up the measures for what works best.
Moore explains, “It’s the first federally funded research effort to look at airborne wind capturing platforms. We’re trying to create a level playing field of understanding, where all of the concepts and approaches can be compared — what’s similar about them? What’s different about them, and how can you compare them?” Useful stuff, getting a set of metrics set up will be critical. Moore knows the field is just being born comparing wind aloft to powered flight, “this is like being back in 1903. Everybody’s got a dog to show. Everybody’s got a different way of doing it.”
Magenn Power Air Rotor System Graphic
NASA and Moore are not alone in the regulation of the skies. The Federal Aviation Administration (FAA) has the power over what goes on overhead. At the beginning of flight there weren’t crowded skies or an FAA to keep things safely organized.
Moore pints out, “Airspace is a commodity. You have to be able to use airspace without disrupting it for other players. Smaller aircraft are still going to need to fly around. Larger airplanes, you can’t expect them to fly around every wind turbine that has a two-mile radius as a protected flight zone.”
Joby Energy System Illustration.
Winds aloft generation does deserve some consideration which Moore hastens to say is not THE answer to clean energy, but deserves consideration with most all other forms of alternative power generation. As of this writing only ethanol has a competitive shot for economical fuel production with fossil fuels. But as land issues continue to press for food, fiber and fuel, everything else has a shot at the market. Sound metrics will help everyone make sensible choices. (More images.)
Winds aloft have some important advantages. Anchors and tethers for airborne wind generation assets don’t require a lot of ground space, nor are they labor intensive, and they don’t pollute. Moore sees potential, “They could stay up a year, then come down for a maintenance check and then go back up, or they could be reeled down in case of a storm. Or one operator could watch over 100 of these.”
The main economic point is the power available in a swept area. Here Moore has some important information to keep in mind. “At 2,000 feet (610 m), there is two to three times the wind velocity compared to ground level. The power goes up with the cube of that wind velocity, so it’s eight to 27 times the power production just by getting 2,000 feet (610 m) up, and the wind velocity is more consistent.”
Higher up, into the 150 mph (240 kph) jet stream at 30,000 feet (9,150 m), and “instead of 500 watts per meter (for ground-based wind turbines), you’re talking about 20,000, 40,000 watts per square meter,” Moore said. “That’s very high energy density and potentially lower cost wind energy because of the 50-plus fold increase in energy density.”
Another motivator is promoting research in the private sector. Answers like where the optimal locations are and the kinds of vehicles are prohibitive to small start up companies. Moore says, “All you have right now are small companies doing the research, and all you can expect of them is to focus on one little piece. They have enough trouble just analyzing their concept without worrying about geography, about ‘where should I mount these so that the wind is optimal?’
The geographical turf is after all the skies above us so it is reasonable to expect that government has a role and acts on it. Moore realizes the oddness, “that there isn’t federal investment in this area, because the questions are just too great for small companies to answer.” The wind energy guys are not all out in the private sector.
The grant money is being used to do two things. One involves the technology and geography. The other involves the interaction between those elements and other competitors for airspace.
That brings us back to the FAA. It’s going to get complicated. The regulations of today will need addressed to accommodate an airspace that includes manned aircraft, the unmanned aircraft in the future, plus wind-borne energy turbines.
Here is Moore’s quote, something to have in mind, “It’s important to understand the concept without regulatory constraints because it lets decision-makers and investors understand the topology of the solution space. We don’t want to just look at the problem with regulatory blinders on, but we don’t just look at it with no blinders on, either. We have to look at it both ways.”
Moore has an insight worth some intense examination – “Offshore deployment of these airborne systems probably makes the most sense in terms of both airspace and land use, because there is little to no demand for low altitude flight over oceans 12 miles (19 to 20 km) offshore. Also, unlike ground-based turbines, there is almost no additional cost for airborne systems offshore because huge platforms are not required to support the structure or resist large tower bending moments.”
What all this has to do with NASA involves some of the core capabilities of the agency in aeronautics, composite materials and air space management. “We’ve shown in the past that NASA’s expertise can help broker and bring an understanding to the FAA as to how these technologies can map into constructive purposes,” said Moore, who has met with wind power energy industry leaders, as well as officials from the National Renewable Energy Laboratory and Department of Energy in undergoing this project.
Moore is offering the FAA NASA’s aeronautical expertise with flying systems. Moore said. “You can’t come up with advanced concepts until you understand the requirements well, and frankly, I don’t think anybody understands the requirements well.”
That humble honesty points out the fundamental value of the study and why a grant is important – it will get the winds aloft questions a sense of what’s going to be necessary to harvest power from the wind.
There should be a huge opportunity offshore as Moore points out. For the coast states doubling up on the grant would make great sense.
The only weakness, not a function of study at this time, is the anchor matter and power transmission. The wave and tidal research has made some progress here. Perhaps the most interesting thing will be to see the design ideas for wind aloft generation.
Go Mr. Moore. Lets get some metrics and geography facts in hand and see where this could go.
By Brian Westenhaus
Source: Catch the Wind Way up High