Wind turbines can offer viable renewable power generation for a cleaner energy future, but the most efficient of them are not suited to any type of urban or small scale installations, so for many of us, they are at least one step removed from our daily lives. We might happen to drive past a large wind power plant and see them in operation, or we may have the opportunity to choose a wind power offset from our power company, but that's probably about as close as we get.
But small scale and urban wind turbines suited to low or turbulent wind conditions could be an option for more of us, if we can get past two big considerations, the visibility and the lower historical efficiency of small turbines. And one new wind turbine prototype takes aim at both of those.
The Libellula (dragonfly) wind turbine, designed by the architects at the Renzo Piano Building Workshop (RPBW) in collaboration with Italy's Enel Green power, could be a viable choice for small-scale electricity generation, with the ability to produce up to 55Kw (sufficient to power up to 15 homes).
"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." - RPBW
The prototype of the Dragonfly wind turbine is currently being tested in Molinetto (Italy), and in two months, has fed over 1200 KWh into the local grid. Testing is said to continue for several months, with mass production for the local market to follow soon afterward.
"We were looking for a new concept in wind turbines. One that would be sensitive to the more frequent low altitude winds in the area. We didn't just want a micro-turbine, but something innovative and modern with no negative impact on the landscape." - Francesco Starace, CEO of Enel Green Power