Energy From the Sky: How Drones Can Generate Electricity

New research into Airborne Wind Energy Systems, funded by a substantial EPSRC grant, seeks to harness high-altitude wind energy using drones, aiming to overcome challenges in system stability and enhance commercial viability, supporting the UK’s net-zero goals. Image of a prototype Kitemill drone in action. Credit: Kitemill

Dr. Duc H. Nguyen has received funding to research Airborne Wind Energy Systems, aiming to improve their safety and efficiency for potential commercialization and a significant role in achieving the UK’s net-zero emissions.

Drones could be crucial in achieving the UK’s net-zero objectives by harvesting wind energy. Dr. Duc H. Nguyen, a Lecturer in Flight Dynamics and Control at the University of Bristol, has received a £375,000 grant from the Engineering and Physical Sciences Research Council (EPSRC) to further explore Airborne Wind Energy Systems (AWES).

By tethering a drone to a ground station, AWES harvests wind power at higher altitudes than conventional wind turbines. The high wind pulls the drone away from the ground station, driving the generator, and producing electricity.

This technology can benefit the UK’s energy sector by reducing its carbon footprint, providing offshore and onshore flexibility, and enhancing the ability to operate in remote areas.

To generate the most power, AWES must fly in intricate patterns while subjected to strong aerodynamic forces. This arrangement creates a complex system with delicate handling characteristics – a slight miscalculation could send the drone tumbling to the ground.

This is the challenge that Dr Nguyen and his collaborators hope to solve during this project. By improving AWES safety and efficiency, he hopes the project will pave the way for AWES commercialization.

Potential and Pitfalls of AWES

Dr Nguyen, from the School of Civil, Aerospace and Design Engineering, explained: “Airborne wind energy has enormous potential and is anticipated to generate €70 billion per year worth of electricity by 2050. However, it is still an emerging technology. In many cases, a trade-off has been made: new designs have been rapidly deployed for test flights before their flying characteristics are fully understood. This has prevented many AWES prototypes from achieving full capacity in operation, leading to early termination of the program and hindering commercialization. This project seeks to address this challenge through the use of bifurcation and continuation methods.”

Dr. Duc Nguyen with Kitemill’s founders, Jon Gjerde (left) and Thomas Hårklau (right), at the Airborne Wind Energy 2024 conference. Credit: Kitemill/Dr Duc Nguyen

These numerical techniques have been successfully used in aircraft dynamic studies to predict dangerous behaviors such as pilot-induced oscillation, flutter, and spin.

Dr. Nguyen concluded: “By replacing existing techniques with bifurcation methods, AWES can achieve significant cost savings and improved performance that will ultimately bring this technology closer to commercialization.”

In addition to the EPSRC funding, the project also benefits from collaborations with two leading players in the sector, Norwegian startup Kitemill and University Carlos the III of Madrid.

Thomas Hårklau, co-founder and Chief Executive Officer of Kitemill, added: “The initiation and successful funding of this AWES project is an important development in the renewable energy sector. AWES technology, with its exceptional material efficiency and higher energy yields, has the potential to become a dominant force in the energy industry. We are excited to collaborate with Duc Nguyen and Bristol University on this initiative. This project not only advances the UK’s net-zero mission but also secures British competence in this emerging sector. Together, we aim to address current challenges and pave the way for the commercialization of AWES.”