From olives it is possible to produce olive oil, but not only! The pomace, a solid residue that remains after the extraction of the oil from the olives, can in fact be further treated to extract pomace oil or it can be used to produce biogas through anaerobic digestion and then biomethane through a biogas upgrading process. Finally, the resultant of anaerobic digestion, digestate, can be used as a fertiliser. Spain, the world's leading producer of olive oil, really has a great deal of potential for the production of biomethane from pomace. How can this huge potential be harnessed? We asked Corradi and Ghisolfi.