This Christmas tree in Hungary is powered by bicycles

A bicycle pedalled by passers-by powers up a Christmas tree-shaped light installation in Budapest, as the local mayor applies sustainable technology to celebrate the festive season while saving on surging energy costs.

The tree only lights up fully while someone keeps pedalling really hard, which encourages families with their kids to stop and give it a try. The bicycle also charges a battery that, along with solar panels, powers up the rest of the lights around the Budapest square.

"One the one hand, we keep moving in this cold weather. On the other, we can experience how much one needs to pedal to light up a six meter-high Christmas tree decoration," said Gergely Orsi, the mayor of Budapest's 2nd district.

"For us, it shows an example that sustainability is the future."

His municipality decided to cancel most of the usual Christmas light decorations this year due to the energy crisis.

"Every year this square is decorated beautifully. We would have been sad if we did not have them this year, but I think this is an excellent compromise," a local resident, Nora, said after she had pedalled the bicycle with her young son watching.