A summer’s afternoon spent among the vines. Sounds idyllic – but for flies and wasps, attracted by the fallen fruit.
With its 48,000 orange trees, the Spanish city of Seville is running a pilot project to generate electricity from the spoiled fruit on its streets.
First 35 tons – from a yearly 5,700 – are sent to a water treatment facility where the methane produced will power the generator.
A single ton of oranges not used for Grand Marnier or jam provides around 50 kWh – supplying five households with enough electricity for one day.
The potential is enormous; purification plants consume around 40% of the energy needed for the city’s water supply.
Excess electricity could be fed back into the grid.