In 1940, the newly built Tacoma Narrows Bridge began to vibrate violently and soon collapsed in windy conditions. Ever since, engineers have focused on ways of stopping their structures vibrating in this way. Now, a group of Spanish engineers is working to harness the energy potential of vibrating structures.
Instead of using the wind to rotate the blades of a wind turbine, Vortex Bladeless uses pillars that shake back and forth from the vortices created by the movement of air around the structure.
Normally, such structure can only be optimized to oscillate at the specific frequencies caused by a particular wind speed, but Vortex Bladeless uses magnets to adjust the turbine on the fly to get the most from any wind speed. Once the structure starts vibrating, an alternator in the base converts the mechanical movement into electricity.
The company claims that its bladeless wind turbines are less expensive to manufacture, require much less maintenance, are totally silent and are safer for birds. On initial testing, individual bladeless turbines captured 30% less energy than conventional turbines but, because they can be located much closer together, a bladeless wind farm can have greater total output.
The company hopes to have 3 metre, 100 kilowatt turbine by the end of 2015, a 13 metre, 4 kilowatt turbine in 2016 and a 1 megawatt turbine within three years.