Rutland Cycling has supplied the bikes for two illuminated pedal-powered Christmas trees sited outside the Royal Festival Hall in London.
Over a kilometre of strung LED tree lights are powered solely by five pairs of pedals per tree. If people stop pedalling, the lights go out.
The display, which is freely open to the public, is part of the Southbank Centre’s Winter Festival which runs until January 7. It was built by Electric Pedal and Vivid Design and includes two children’s BMX bikes and two hand-bikes for those unable to pedal.