Seville’s Buses will soon be running on orange juice that will be extracted from the fruit and turned into a new biofuel
The buses of the future in Seville will run on orange juice! The city is taking advantage of the fact that it has the largest urban orange grove in Europe, with a harvest of more than 3,000 tons. Tests on a system are currently underway to extract biogas for engines and generate electricity: using 500 litres of squeezed fruit.
It seems that this urban harvest is finally bearing fruit – pun intended!
The peak collection period for oranges in Seville typically occurs between January and February, with the final harvests concluding in March. While only a small portion of these oranges are currently collected, a growing number are being sent to the El Copero sewage treatment plant (EDAR) run by the Metropolitan Water Company (Emasesa).
Here, the plant is able to extract energy from the fruit, in addition to the sludge produced during purification. Since 2020, the process has involved using a large juicer to extract juice from the oranges, which is then transferred to enormous tanks for an anaerobic digestion process. During this biological treatment, bacterial communities act in the absence of oxygen to convert the juice into energy.
Seville boasts the unofficial title of being the largest urban orange grove in Europe, thanks to its almost 48,000 trees lining its streets. If we include private urban areas, as well as spaces such as the Alcázar gardens or the Alamillo, this number exceeds 50,000. With such an abundance of orange trees, it’s no surprise that the yearly harvest can be enormous, with each tree producing between 45 and 130 kilos of fruit, translating to almost three million kilos in 2022 alone.
In fact, some seasons have seen yields of up to five million kilos! However, due to the bitter taste of these oranges, most of this urban harvest used to end up in landfills. But not anymore. Thanks to an experimental plant, these orange remains are now being transformed into biogas that generates electricity, with the ultimate goal of powering urban buses in the future.
