This bridge is covered in solar panels

They’re calling it the “world’s largest solar powered bridge,” and who’s to argue? We haven’t seen a bigger one than 4,400-panel-covered Blackfriars rail bridge that spans the Thames in central London.

The new London Blackfriars station opened in 2012, in time for the Olympics, making way for more and longer trains and providing station entrances on either bank of the Thames. The panels over the rail bridge have been in place for a while now, but this week Britain’s rail infrastructure company, Network Rail, officially unveiled them in a fashion only the British could come up with: They served up nearly 80,000 cups of tea, an amount that could be made from the bridge’s average daily power output.

Blackfriars Bridge, London (image via Network Rail)

The panels on the bridge, which connects north and south London in the center of the city, cover some 6,000 square meters, Network Rail said – about 1.5 acres. That’s a good-sized system, adding up to 1.1 megawatts of generating capacity. Network Rail said that at peak output the system could provide as much as half the station’s electricity needs, and that over the course of a year it would avoid 511 tons of CO2 emissions.

image via Network Rail

That said, London isn’t the sunniest place in the world, and the 900,000 kilowatt-hours of annual generation forecast for the bridge means that the array of Sanyo panels will deliver a modest 9.3 percent capacity factor. For comparison, utility-scale solar arrays in the sun-drenched U.S. Southwest  deliver more than 25 percent capacity factors.

* Pete Danko,