Teenage pedal power was used to charge the Rome stage where climate activist Greta Thunberg gave a speech.
Around 128 bicycles were rigged up to a dynamo and generator in Piazza del Popolo.
They powered the stage that hosted Thunberg on Friday as she spoke to Italian students about her drive to get governments to act faster on combatting climate change.
The 16-year-old arrived in Italy on Wednesday. Her visit included meeting Pope Francis and addressing Italian senators.
Thunberg shot to prominence last August, taking a place on the cobblestones in front of Stockholm's Parliament House with her "school strike for climate" sign.
Students around the world have since copied her and youth organisations have launched school strikes involving students in more than 40 countries.