Viaducts–the technical term for arch-supported bridges–are already impressive swoops of engineering prowess. But this kind of infrastructure is about to get even more amazing, as giant spinning turbines are hung from the spans.
The Juncal Viaduct in the Canary Islands is serving as a model for the project, completed by researchers from Kingston University in London. The scientists’ calculations show that installing turbines between its tall legs would produce enough power for 450 to 500 homes, or around half a megawatt. “This kind of installation would avoid the emission of 140 tons of CO2 per year, an amount that represents the depuration effect of about 7,200 trees,” Oscar Soto, a researcher on the project, told the Spanish-language SINC.
Soto’s team determined that multiple small turbines work better than a single large unit in these cases, although of course their size is determined by the design of the host viaduct. “The bigger the rotor surface, the more power can be extracted,” said Soto. The optimum deployment for the Juncal Viaduct would be 24 small turbines, but cost and practicality led the researchers to settle on the two-turbine design pictured above.
Using viaducts for wind power is a clever idea. Much infrastructure is already in place, and it’s a great way put turbines in populated areas, where there isn’t enough space to erect giant windmills–although local BASE jumpers may not agree.