Many have tried to get an airborne wind energy harvesting device off the ground, and many have failed. Nevertheless, the US Marine Corps (USMC) is among those continuing to support the technology. The allure of lightweight, transportable wind power from the skies still burns bright, and a recent proposal from the US Renewable Energy Laboratory suggests that the USMC just might be on to something.
At this writing, Russian President Vladimir Putin seems intent on murdering as many people in Ukraine as he can. Millions are fleeing and in need of assistance. To help refugees from that conflict and others, donate to Doctors without Borders or other reliable aid organizations.
Why Airborne Wind Energy?
The cost of wind energy has been sinking like a stone, thanks to a string of improvements in turbine technology. The sites available for wind energy infrastructure have also been increasing exponentially. Floating turbines are widening the span of offshore development, and taller towers can bring turbines into regions where low-altitude wind speeds are less than optimal.
So, why bother trying to launch a wind turbine into the air? The key word is infrastructure. Whether onshore or off, wind turbines require massive towers, which involve cost and transportation issues. Even in the area of smaller turbines, weight and transportability can be limiting factors.
That explains why some renewable energy innovators persist in clinging to the airborne wind energy dream. The basic idea is to float your wind harvesting device into the sky, in the form of a kite or glider. That reduces your infrastructure needs down to a relatively inexpensive, lightweight tether and some kind of anchor.
In addition, the tether setup enables the device to be sent into higher altitudes where wind speeds are optimal. The estimated target altitude ranges up to 800 meters, far higher than the tallest wind turbine tower.
Due to its relatively tiny footprint and its high degree of transportability, airborne wind energy technology could open up a whole new vista of sites and use cases.
Airborne Wind Energy Not Yet Ready For Prime Time – Yet
That all sounds good on paper, but the devil is in the details. Back in 2017, CleanTechnica took one last, close look at the airborne wind energy field when Google (now Alphabet) was still trying to send its ambitious Makani turbine project skyward. The device vaguely resembled a glider, and the tiny sailing turbine startup Ampyx was attempting a similar design around the same time.
Alphabet shut down the Makani project in 2000, but Ampyx is still working on a pre-commercial version of its AP3 device, and that’s a good thing because all that hard work could still pay off.
Last year, the National Renewable Energy Laboratory took a deep dive into the airborne wind energy area and came up with a proposal to develop a 10-year R&D plan.
The report, simply titled “Airborne Wind Energy,” takes pains to describe significant obstacles and challenges. However, the authors also argue that AWE should not be viewed as some kind of failed offshoot of the wind energy field. Instead, they make the case for AWE to be treated as its own, unique early-stage renewable energy technology of the 21st century.
Through that lens, the potential for next-level development is similar to that in the early stages of conventional wind turbines as well as solar panels, electric vehicles and other clean technologies of the 21st century.
“The research and development challenges of AWE are similar in complexity to those in other precommercial renewable energy technologies, wherein a variety of technological solutions are under development and convergence has not been reached and would require a similar magnitude of dedicated investment to harvest the significant technical potential,” the report explains.
USMC Making The Case for Next-Level AWE
The report shies away from anticipating the kind of widespread commercial deployment enjoyed by the traditional land and offshore wind industry today. However, it does identify several important use cases for AWE that could attract early adopters. That includes the distributed wind sector, which refers to producing and consuming renewable energy on site, or within a limited area. That could include remote villages, agricultural operations, industrial campuses, and more.
The report also foresees use cases in tandem with traditional fixed or floating offshore turbines. That seems a reasonable projection, considering that the offshore sector is already beginning to offer piggyback rides to solar panels, wave devices, and green hydrogen-producing electrolyzers, so why not pile on an AWE.
All in all, NREL takes a cautious approach, but the report does conclude that the development of a 10-year plan for AWE is worth considering. The near term period of 1-4 years would focus on foundational research, feasibility studies and building collaborative networks, followed by a mid-period effort aimed at supporting industry stakeholders and accelerating the development of pre-commercial systems and prototypes.
US Marine Corps Not Waiting Around For Your 10-Year Plan
By the time years 6-10 roll around, NREL expects the most promising concepts to emerge and begin launching in early-adopter settings. In an interesting turn of phrase they include “progressive” utilities in that category, which could be a reference to the ability of rural electric cooperatives to adopt innovative solutions for power generation.
Apparently the US Marine Corps is not waiting around to see what happens next. Among other decarbonization projects, the USMC has been working with the firm Windlift since 2011, when the company won a small business grant to develop its trailer-mounted, 24-kilowatt Airborne Power Generator.
Twenty-four kilowatts may sound like peanuts compared to the 12-13-megawatt range of conventional wind turbines. It is peanuts, but the USMC is an expeditionary force. They can’t drag a conventional wind turbine of any size along with them, except possibly in the area of micro turbines, in which case the law of diminishing returns may kick in.
The mobility factor is so significant that Windlift and USMC are now collaborating on a downsized version. Called the Man Portable Wind Energy System, the new version aims at just 6 kilowatts, but it weighs only 440 pounds.
As described by Windlift, the new version can be deployed in less than 30 minutes, and its 500-foot altitude could also accommodate surveillance and communications activity.
More Renewable Energy For USMC
That 500-foot deployment may limit some use cases in terms of giving away your position, but it could also open up new opportunities for USMC to scavenge energy on-the-go, which is the whole point.
Back in 2009, CleanTechnica took note of USMC’s transition to an energy-scavenging model when it introduced new, portable solar-in-a-suitcase technology aimed at planting energy resources in the field of operation.
That program comes under the umbrella of GREENS for Ground Renewable Expeditionary Energy Network System. Windlift states that its wind energy device could deliver a renewable energy density seven times greater than the GREENS system, providing the force with an additional energy-scavenging tool depending on conditions in the field.
As for USMC’s long term interest in renewables, Russia’s homicidal rampage through Ukraine is the latest demonstration that agility and supply lines are the key elements in modern warfare. The availability of energy resources near or in the field can make all the difference in a unit’s ability to fight, fuel, and move, and USMC seems keenly aware that renewable resources fit the bill.
“Your forward contact forces that are deterring every day are your fighting forces. They’ll be asked to operate in small, distributed groups, capable of taking a location, using it to refuel and rearm planes, strike a target or move supplies, and then pack up and move to a new location within 48 to 72 hours,” explains Commandant of the Marine Corps Gen. David Berger.
Berger is cited in a USMC article published last year under the title, “Corps’ Power, Water Systems Are Getting Lean And Going Green,” which provides a good recap of USMC’s renewable energy and energy efficiency measures.
The article also cites Master Sgt. Keith Hoy, who is a project officer with the Power Systems Team at MCSC, which oversees the GREENS system.
“A big focus of the power team right now is fielding systems that increase efficiency and mobility on the battlefield,” Hoy said, listing wind energy along with new battery chemistries and other fuel efficiency measurements.
The focus is absolutely on force efficiency and effectiveness, but since the Department of Defense lists climate change as a significant national security threat, decarbonizing military operations is a bonus benefit.
The jury is still out on airborne wind energy, but then again, look where the green hydrogen market was just 5 years ago, let alone 10.
Follow me on Twitter @TinaMCasey.
Image: Airborne wind energy device courtesy of Windlift.