Constructed to take advantage of lightweight and resilient composite materials (carbon, polycarbonate), the slim, 35cm-diameter mast stands only 20m high, and is secured to the ground with cables.
The Libellula is able to harness even the lightest breezes, requiring winds of only 2m/second to power it more or less continuously. This also means that it can be installed successfully at low altitudes.
The turbine has been designed to have a minimal visual impact and has only two blades, rather than the more usual three. When the turbine is not turning, the blades align vertically with the mast.
The turbine blade was inspired by the transparent wing of a dragonfly, from where the turbine gets its name. Transparent plexiglass panels in the blade are intended to show off the carbon structure inside.
Enel plans to use the Libellula in Enel Green power plants in Italy, but also hopes that the turbine will be taken up in the future for small-scale domestic generation.
Client: ENEL Green Power SpA
Renzo Piano Building Workshop, architects
Design Team: S.Scarabicchi, E.Donadel (partner and associate in charge), M.Rossato Piano
Consultants: Favero & Milan (structural, consulting executive architect); Metalsystem (mechanical service engineering and construction)