UCOs are oils and fats that have been used for cooking or frying in the food processing industry, restaurants, fast foods and at consumer level, in households. The European Waste Catalogue (EWC) classifies them as Municipal Wastes (household waste and similar commercial, industrial and institutional wastes) including separately collected fractions, under the code 20 01 25 (edible oils and fats). UCO obtained from waste water treatment plants is also considered non‐hazardous materials with a different code: 19 08 09 (grease and oil mixture from oil/water separation containing edible oil and fats).
It is estimated that currently around 90% of cooking oils and fat used in the EU are produced from vegetable oils, whereas in countries such as Belgium relatively large quantities of animal fats are used (Peters et al, 2013). According to EU estimations, the potential UCO to be collected is around 8L UCO/capita/year. Extrapolated to the total EU population of around 500 million, this means that 4 Mton of UCO is the annually capacity – seven times more than the current collected amount. This potential increases around 2% per year, following the annual increase of cooking oil usage in the EU‐15. In order to achieve this level of collection, the collection infrastructure should be improved.