The remains of food from restaurants and markets of the metropolitan area of Lisbon (north) are sent to Valorsul's Biodegradable Waste Recovery Plant.

In this plant the remains of food are treated and transformed into organic agricultural corrective, without chemical additives, for use in agriculture and gardening.

Through the process of "anaerobic digestion" it is also possible to capture the gas from the fermentation (biogas) and use it in the production of electric energy.