Swiss Kite Power project testing in the Alps (19 July 2010).
TwingTec’s vision: TwingFarm (2015). 70
Corey Houle Co-founder and CTO
Twingtec AG Überlandstrasse 129 8600 Dübendorf Switzerland correy.houle@twingtec.ch www.twingtec.ch
Mobile Wind Farms Using Tethered Wings
– Technical and Economic Considerations
Corey Houle1,2, Dino Costa1,3, Cédric Galliot1,3, Flavio Gohl1,3, Rolf H. Luchsinger1,3 1TwingTec AG
2Institute of Aerosol and Sensortechnology, FHNW 3Center for Synergetic Structures, Empa
The construction of convention wind farms requires large amounts of capital and in order to be economical these costs must be amortized over a long project lifetime, typ-ically 20 years. Airborne wind energy systems, by employ-ing tethered wemploy-ings coupled to ground based generators, enable a highly mobile power plant concept whereby the entire plant can be quickly transported and installed, even in remote locations. Due to this low cost of instal-lation, a temporary power plant can be realized, a novel concept in the field of renewable energy.
In order to reach power outputs of interest for industrial applications, typically in the MW range, an array of teth-ered wind energy systems can be utilized. By integrating the ground based generators and all other power conver-sion hardware into standard shipping containers logisti-cal difficulties and expenses can be minimized. Balance of plant, such as foundations, cables, switchgear, trans-formers and medium voltage distribution lines can be constructed from standard components, although spe-cial considerations are required to maintain flexibility and minimize costs. Grid integration, which can be partic-ularly difficult for isolated grids powered by diesel gener-ators, can be realized using techniques employed by the solar PV industry. Risk mitigation, an important part of every power project, necessitates a wind resource assess-ment and the impleassess-mentation of a comprehensive
opera-tional safety scheme, both of which require special atten-tion due to the nature of the technology employed. An economical project implies that energy can be pro-duced and delivered to the customer at a similar or lower cost than their baseline power supply. For off-grid ap-plications, typically powered by diesel generators the cost of supply is dominated by the fuel costs, including transportation, storage and taxes. For renewable energy projects, the cost structure is dominated by the up-front capital costs, with operation and maintenance making a smaller contribution to the final cost of energy. Airborne wind energy systems have a cost structure somewhere in between conventional renewables and fuel based gener-ators, with lower capital costs due to reductions in ma-terial utilization and balance of plant requirements and higher operation and maintenance costs due to periodic replacement of tethers and wings.
Based on discussions with industry experts, energy con-sumers and independent power providers, a concept for a mobile wind farm using tethered wings has been devel-oped. The technical and economic feasibility of such a project will be presented as well as the practical and fi-nancial challenges to realizing such a system. A first look at TwingTec’s unique system concept for airborne wind energy allowing for fully autonomous operation, includ-ing launchinclud-ing and landinclud-ing, will be given.
WIND ENERGY 2.0
