This year, the world's largest solar bridge was brought online in London, United Kingdom. The Blackfriars Bridge holds 4,400 roof-mounted solar panels over a 6,000 square meter area. These panels are expected to supply half of the energy needs of the Blackfriars rail station, or about 900,000 kWh per year.

Photo Credit: Photo of Blackfriars bridge in London, UK by/copyright Dr. Francis Li and used with his permission.