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Power to the airborne wind energy performance model: Estimating long-term energy production with an emphasis on pumping flexible-kite systems

Schelbergen, M. (author)

The potential of utility-scale airborne wind energy (AWE) systems to contribute significantly to the energy transition hinges on their large-scale deployment, which depends on the cost-competitiveness and complementarity with conventional wind turbines. Central to the assessment of these metrics is understanding long-term energy production,...

doctoral thesis 2024

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How do residents perceive energy-producing kites?: Comparing the community acceptance of an airborne wind energy system and a wind farm in Germany

Schmidt, H.S. (author), Leschinger, Valentin (author), Müller, Florian J.Y. (author), de Vries, G. (author), Renes, Reint Jan (author), Schmehl, R. (author), Hübner, Gundula (author)

Airborne wind energy (AWE) is an emerging renewable energy technology that uses kites to harvest winds at higher altitudes than wind turbines. Understanding how residents experience a local AWE system (AWES) is important as the technology approaches commercialization. Such knowledge can help adjust the design and deployment of an AWES to fit...

journal article 2024

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An Aero-Structural Model for Ram-Air Kite Simulations

Thedens, Paul (author), Schmehl, R. (author)

Similar to parafoils, ram-air kites are flexible membrane wings inflated by the apparent wind and supported by a bridle line system. A major challenge in estimating the performance of these wings using a computer model is the strong coupling between the airflow around the wing and the deformation of the membrane structure. In this paper, we...

journal article 2023

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Conformable Inflatable Wings Woven Using a Jacquard Technique

Breuer, J.C.M. (author), Luchsinger, Rolf (author), Schmehl, R. (author)

Inflatable wings are of interest for applications where low weight, compact transport volume, and easy set-up are important. Examples are unmanned aerial vehicles with inflatable wings, paragliders and softkites for sport or airborne wind-energy applications. In this paper, a new method of designing and fabricating conformable inflatable wings...

journal article 2023

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Operation Approval for Commercial Airborne Wind Energy Systems

Salma, V. (author), Schmehl, R. (author)

Integrating the operation of airborne wind energy systems safely into the airspace requires a systematic qualification process. It seems likely that the European Union Aviation Safety Agency will approve commercial systems as unmanned aircraft systems within the “specific” category, requiring risk-based operational authorization. In this paper,...

journal article 2023

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Low- and High-Fidelity Aerodynamic Simulations of Box Wing Kites for Airborne Wind Energy Applications

Eijkelhof, D. (author), Buendía Vela, Gabriel (author), Schmehl, R. (author)

High aerodynamic efficiency is a key design driver for airborne wind energy systems as it strongly affects the achievable energy output. Conventional fixed-wing systems generally use aerofoils with a high thickness-to-chord ratio to achieve high efficiency and wing loading. The box wing concept suits thinner aerofoils as the load distribution...

journal article 2023

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Fast Aero-Structural Model of a Leading-Edge Inflatable Kite

Cayon, O. (author), Gaunaa, Mac (author), Schmehl, R. (author)

Soft-wing kites for airborne wind-energy harvesting function as flying tensile membrane structures, each of whose shape depends on the aerodynamic load distribution and vice versa. The strong two-way coupling between shape and loading poses a complex fluid-structure interaction problem. Since computational models for such problems do not yet...

journal article 2023

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Life-Cycle Assessment of a Multi-Megawatt Airborne Wind Energy System

van Hagen, L.J.A. (author), Petrick, Kristian (author), Wilhelm, Stefan (author), Schmehl, R. (author)

A key motivation for airborne wind energy is its potential to reduce the amount of material required for the generation of renewable energy. On the other hand, the materials used for airborne systems’ components are generally linked to higher environmental impacts. This study presents comparative life-cycle analyses for future multi-megawatt...

journal article 2023

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Value-Driven System Design of Utility-Scale Airborne Wind Energy

Joshi, R. (author), Kruijff, Michiel (author), Schmehl, R. (author)

In the current auction-based electricity market, the design of utility-scale renewable energy systems has traditionally been driven by the levelised cost of energy (LCoE). However, the market is gradually moving towards a subsidy-free era, which will expose the power plant owners to the fluctuating prices of electricity. This paper presents a...

journal article 2023

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Sizing of Hybrid Power Systems for Off-Grid Applications Using Airborne Wind Energy

Reuchlin, S.P.A. (author), Joshi, R. (author), Schmehl, R. (author)

The majority of remote locations not connected to the main electricity grid rely on diesel generators to provide electrical power. High fuel transportation costs and significant carbon emissions have motivated the development and installation of hybrid power systems using renewable energy such these locations. Because wind and solar energy is...

journal article 2023

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Modelling Aero-Structural Deformation of Flexible Membrane Kites

Poland, J.A.W. (author), Schmehl, R. (author)

Airborne wind energy systems using flexible membrane wings have the advantages of a low weight, small packing volume, high mobility and rapid deployability. This paper investigates the aero-structural deformation of a leading edge inflatable kite for airborne wind energy harvesting. In the first step, a triangular two-plate representation of the...

journal article 2023

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Dominant Designs for Wings of Airborne Wind Energy Systems

van der Burg, S. (author), Jurg, M.F.M. (author), Tadema, F.M. (author), Kamp, L.M. (author), van de Kaa, G. (author)

This paper focuses on the design of the wings used in airborne wind energy systems. At the moment, two different designs are being developed: soft wings and rigid wings. This paper aimed to establish which of the two alternative design choices has the highest chance of dominance and which factors affect that. We treated this problem as a battle...

journal article 2022

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Six-degrees-of-freedom simulation model for future multi-megawatt airborne wind energy systems

Eijkelhof, D. (author), Schmehl, R. (author)

Currently developed airborne wind energy systems have reached sizes of up to several hundred kilowatts. This paper presents the high-level design and a six-degrees-of-freedom model of a future fixed-wing airborne wind energy system operated in pumping cycles. This framework is intended to be used as an open-source reference system. The fixed...

journal article 2022

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Effect of Chordwise Struts and Misaligned Flow on the Aerodynamic Performance of a Leading-Edge Inflatable Wing

Viré, A.C. (author), Lebesque, G.H.M. (author), Folkersma, M.A.M. (author), Schmehl, R. (author)

Leading-edge inflatable (LEI) kites use a pressurized tubular frame to structurally support a single skin membrane canopy. The presence of the tubes on the pressure side of the wing leads to characteristic flow phenomena for this type of kite. In this paper, we present steady-state Reynolds-Averaged Navier-Stokes (RANS) simulations for a LEI...

journal article 2022

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The Social Acceptance of Airborne Wind Energy: A Literature Review

Schmidt, H.S. (author), de Vries, G. (author), Schmehl, R. (author), Renes, Reint Jan (author)

Airborne wind energy (AWE) systems use tethered flying devices to harvest higher-altitude winds to produce electricity. For the success of the technology, it is crucial to understand how people perceive and respond to it. If concerns about the technology are not taken seriously, it could delay or prevent implementation, resulting in increased...

journal article 2022

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Robust Automatic Pumping Cycle Operation of Airborne Wind Energy Systems

Rapp, S. (author)

Airborne wind energy (AWE) is a novel technology that aims at accessing wind resources at higher altitudes which cannot be reached with conventional wind turbines. This technological challenge is accomplished using tethered aircraft or kites in combination with either onboard or ground-based generators. In the former case, the kinetic energy of...

doctoral thesis 2021

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Combined Airborne Wind and Photovoltaic Energy System for Martian Habitats

Ouroumova, L.H. (author), Witte, D. (author), Klootwijk, B.J. (author), Terwindt, E.N. (author), van Marion, F. (author), Mordasov, D. (author), Corte Vargas, F. (author), Heidweiller, S. (author), Géczi, M. (author), Kempers, M.X. (author), Schmehl, R. (author)

Generating renewable energy on Mars is technologically challenging. Firstly, because, compared to Earth, key energy resources such as solar and wind are weak as a result of very low atmospheric pressure and low solar irradiation. Secondly, because of the harsh environmental conditions, the required high degree of automation, and the exceptional...

journal article 2021

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Electricity in the Air: Insights From Two Decades of Advanced Control Research and Experimental Flight Testing of Airborne Wind Energy Systems

Vermillion, Chris (author), Cobb, Mitchell (author), Fagiano, Lorenzo (author), Leuthold, Rachel (author), Diehl, Moritz (author), Smith, Roy S. (author), Wood, Tony A. (author), Rapp, S. (author), Schmehl, R. (author)

Airborne wind energy systems convert wind energy into electricity using tethered flying devices, typically flexible kites or aircraft. Replacing the tower and foundation of conventional wind turbines can substantially reduce the material use and, consequently, the cost of energy, while providing access to wind at higher altitudes. Because the...

review 2021

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Exploring design dominance in early stages of the dominance process: The case of airborne wind energy

van de Kaa, G. (author), Kamp, L.M. (author)

This paper is about Airborne Wind Energy Systems, a promising new wind power generating system that, although technologically possible to realize, is not available on the market yet. Currently, many different technological options for the systems are being developed. One question for such systems is where to position the generator, on the...

journal article 2021

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Identification of kite aerodynamic characteristics using the estimation before modeling technique

Borobia-Moreno, R. (author), Ramiro-Rebollo, D. (author), Schmehl, R. (author), Sanchez Arriaga, G. (author)

The aerodynamic characteristics of a leading edge inflatable (LEI) kite and a rigid-framed delta (RFD) kite were investigated. Flight data were recorded by using an experimental setup that includes an inertial measurement unit, a GPS, a magnetometer, and a multi-hole Pitot tube onboard the kites, load cells at every tether, and a wind station...

journal article 2021