The EA have had queries about whether particular feedstocks used in anaerobic digestion (AD) plants are waste or not. This is important because it will affect whether they regulate AD plants and the use of the digestate produced by them. AD plants that take feedstocks consisting of or containing waste require an environmental permit or a relevant exemption. Plants that take only non-waste feedstocks currently do not.

Similarly, use of any AD digestate that is classified as waste will require an environmental permit or relevant exemption. For many types of feedstock the question of whether or not they are wastes is very straightforward. For some types of feedstocks, for example crop residues, it is not. There are circumstances where crop residues being sent to an AD plant by the producer are by-products (i.e. not waste). This note, which draws on existing guidance from Defra and the European Commission, provides some clarity around these circumstances. N.B Energy crops (i.e. crops intentionally grown specifically for use as feedstocks for AD plants) are not wastes and are not the subject of this briefing note.