Intelligent rotor blades – an example of innovation through research

Wind power units can be made much more efficient using smart technologies: so-called "smart blades" can adapt faster and better to local wind currents and so generate more electricity. How the idea can be made to work is being studied in a research project funded by the Federal Ministry for Economic Affairs and Energy – one of many in the field of renewable energy.

Technical sketch of an intelligent rotor blade© DLR (CC-BY 3.0)

If the wind blows too strong, operators often have to turn their wind turbines out of the wind, for all practical purposes interrupting generation. That involves loss of revenue and adverse consequence for the economic viability of the units. Because the long rotor blades can only be adjusted as a whole and relatively slowly, they cannot adapt to different wind speeds within a gust. However, such gusts are common when the wind is strong – in fact, modern rotor blades can be up to 85 metres long, and each turn sweeps an area as big as several football pitches.

Intelligent rotor blades, also known as "smart blades," are more versatile here, because they can adapt better and faster to local wind currents: "passive" smart blades can not only bend but turn around their own axis; "active" smart blades achieve the same adaptability thanks to pliable components or built-in adjustable flaps. These smart blades are being studied in a project, funded by the Federal Ministry for Economic Affairs and Energy (BMWi) with 12 million euros, in which the Fraunhofer Institut für Windenergie und Energiesystemtechnik IWES, the ForWind Zentrum für Windenergieforschung and the German Aerospace Center (DLR) are co-operating. This is just one of many research and development projects in the field of renewable energy that the BMWi is sponsoring.

More funding for research into renewable energy

The Federal Government has bundled all its funding schemes for the Energy Transition in the BMWi. In early 2015, the "renewable energy" and "energy efficiency" promotion areas were networked even more closely and the focus of project funding shifted to the energy chain as a whole: from energy production and conversion, via transportation and distribution to the end uses of energy in industry or the buildings sector. This re-alignment of applied research funding in the energy context opens up new possibilities through interdisciplinary approaches.

The funding provided for research and development projects in the field of renewable energy sources has more than trebled since 2004. In the last three years alone, it has risen significantly from 129 million euros in 2011 to now 178 million euros in 2014. The aim is to further strengthen the renewables through innovation and new technologies and to accelerate their integration into the supply system.

Most of the funding is dedicated to evolving the technologies that make the biggest contribution to the growing share of electricity generated from renewable energy sources: wind power and photovoltaics. The largest increase has been in funding for research into the interplay within the energy supply system of the future: this includes for example technologies such as energy storage or intelligent grids. In 2014, 114 new projects were approved in this area, for which a total of 52 million euros have been made available.