A computer powered by its own wind turbine is being set up at a Cardiff school as part of the city's aim to reduce its "carbon footprint".
The computer, at Fitzalan High School, is one of a number of measures being undertaken to reduce energy waste, including light controls in classrooms.
The city council wants to reduce carbon emissions by 60% from its non-domestic buildings and waste by 2018.
Carbon dioxide (CO2) emissions are thought to be linked to climate change.
A newly-refurbished swimming pool has been fitted with a cover to reduce heating and ventilation costs at the school.
Energy-efficient, eco-quiet computers have also been introduced, including the wind-powered model, to illustrate renewable energy to pupils.