Imagine a hi-tech kite that, instead of flying in the wind, generates electricity by tirelessly performing figure eights in the sky. This is exactly what the wing drone developed by Wind lift, a North Carolina startup that aims to revolutionize the world of off-grid wind energy.
This technology could bring electricity to even the most remote places, with a lower cost and footprint than traditional wind turbines. Here's what it's all about.
A “kite” that generates electricity by flying
The heart of the Windlift system is a drone with a wingspan of approximately 3,7 meters, with electric generators integrated into the wings. The aircraft is anchored to the ground by a steel cable of approximately 60 meters, which also acts as a conductor for the electricity generated.
The take-off is vertical, like a helicopter, until the cable is completely taut. At that point, the drone begins a series of spectacular lateral “dives”, always keeping the cable taut, to then rise and reverse direction in an eternal figure-eight flight.
In engineering and aeronautical terms, this is called “crosswind flight.” A technique used to maximize lift or thrust by flying perpendicular to the direction of the wind.
In the case of Windlift, the goal is to generate off-grid energy. With each “dive”, the rotors of the lightweight carbon fiber frame (11-13 kg) are crossed by a flow of air which generates a thrust of 2-5 G, alternating traction and resistance phases. The electricity thus produced, approximately 30 kWh, is sent directly to the ground station, which can be connected to a battery, a domestic utility, the municipal grid or any other destination.
Portable and affordable wind energy
Thirty kilowatt hours may seem small compared to a modern 26 MW offshore wind turbine, capable of powering 8.500 homes. But Windlift's strong point is another: portability and low cost. According to the company, its system It is approximately 80% less expensive than traditional wind turbines and requires 90-95% less materials.
It can also provide power to the most remote locations with minimal installation. All features that have attracted the attention of the U.S. Department of Defense, which has awarded Windlift a $30 million research and development grant. In return? Portable systems for powering advanced operating stations.
The Future of “Flying” Off Grid Energy
Windlift is currently designing a 75 kWh system with a 12-meter wingspan for commercial applications. The company says going beyond that size would be counterproductive due to the cube-square law, which would make the system less efficient and less portable. A 12-meter frame can still be transported in a standard shipping container.
Windlift is not the first to explore this technology. In 2016, the project Eat Google X Labs was the first in the world to generate off-grid energy with a “flying” kite, aiming for industrial-scale systems of 600 kWh.
After an initial investment of $15 million and full acquisition by Google in 2013, however, the project was shut down in 2020. Reason? Too risky.
Perhaps by focusing on portability and small scale, Windlift can find a niche for this technology. In a world increasingly hungry for clean, affordable energy, solutions like this could really take off, bringing wind electricity where giant turbine blades can’t reach.
