As wind power quickly spreads—thanks to the fact that it's now cheaper than coal in some places—it usually ends up in sprawling wind farms. But some designers are hoping that it will start to show up in a more unlikely spot: under bridges.
Architects first proposed the idea a few years ago in Italy, as the government considered what to do with massive viaducts crossing the Italian countryside. The plan was to tear down the old bridges, at a cost of around $40 million, as new roads and tunnels were built somewhere else. The architects suggested an alternative—why not turn the old structures into new sources of renewable power?
"Rather than demolishing the old route completely, including the extraordinary concrete viaducts—fully integrated within the landscape and the collective imagination—this old route could experience a second life," says Francesco Colarossi, architect at a Rome-based firm called Coffice.
By hanging wind turbines under the bridges, the design can capture some of the highest wind speeds while avoiding any impact from construction on land. "The integration of the turbines within an existing structure allows avoiding the exploitation of natural areas that are still immaculate," he says. "In Italy many country landscapes have been filled with towers ... and sometimes it’s really a pity. Imagine the hills of Tuscany filled with wind turbines."
On top of the bridge, the design includes solar panels to provide even more electricity; the architects calculated that it could generate enough to power 5,000 homes, and pay for itself with about a decade. After the Italian economy slowed, the project didn't move forward. But now the designers are hoping that it can find new life elsewhere.
"In Italy, because of the [financial] crisis, the project has been stopped," says Colarossi. "But we are hopeful to present this project in other countries . . . Who knows?" In theory, the design could work under any bridge or railway with the right wind conditions. Done right, it can also have the extra benefit of making old bridges stronger.
A team of researchers recently studied a similar concept in Spain—with a scaled-down design to save cost—and concluded that it could really work.