- Blackfriars bridge in the City of London is the world's largest solar-powered bridge.
- Over 4,400 photovoltaic cells occupy a roof area of 6000 square meters.
- Clean energy provides 50 percent of the requirements of Blackfriars railway station, located on the bridge.
- The array is estimated to reduce carbon emissions by 511 tonnes per year.
Over 4,400 solar panels compose the roof of Blackfriars bridge in the City of London, making it the largest solar-powered bridge in the world.
The old Victorian bridge was built across the river Thames in 1886, but unlike other bridges throughout the city, it also operates as a railway station to serve commuters from all the surrounding areas, while offering a stunning view.
Being the first station to span the river Thames, the bridge has always had high demands on power.
In 2009 it received a makeover: the wrought-iron bridge was dismantled and rebuilt to generate its own power using the sun.
A new roof was installed, housing solar panels over 6000 square meters, which is enough to cover 23 tennis courts. On a sunny day, the canopy can produce up to a megawatt of electricity.
The bridge reopened in 2012 and the installation of the array was part of a larger upgrading project involving the station as a whole to cater for more passengers and improve services.
"It generates enough electricity to make about 80,000 cups of tea a day," explains Chris Binns, head of engineering at Network Rail who led the upgrade.
The use of solar power now provides up to 50 percent of the energy needed at the station and is estimated to reduce carbon emissions by 511 tonnes per year.
The increased production of solar panels worldwide, particularly in China, has brought the previously high expense of solar cells plummeting down to make designs like this more affordable.
"It's a wonderful showcase of how Britain can actually build something that's significant," says Professor Ned Ekins-Daukes, an expert on solar energy at Imperial College London. "This is the most powerful bridge in the world and it's using solar power in Britain, not a country well known for its sunshine."
Cities across the world are increasingly harnessing the sun's energy, with landmarks as iconic as the Eiffel tower and Taj Mahal planning to incorporate solar panels into their architecture.
If the gray skies of London can accomplish such results across the Thames, imagine the potential elsewhere.
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