The Environment Agency (EA) has issued a briefing note outlining that anaerobic digestion (AD) facilities that only use certain types of crop residues as input will not need to hold an environmental permit.

The note, issued earlier this month, was published to help clarify what types of feedstock are considered wastes, and which are not.

It reads: ‘We 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 we 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.’

According to the EA, there ‘may be a very small number of existing operators who have an environmental permit for an AD plant, where the feedstocks are only crop residues or crops plus crop residues’.

Exemption criteria

The briefing note outlines that as long as the feedstock is made entirely of: purpose-grown crops; crop residues such as misshapen, bruised or undersized fruit and vegetables (kept separate from other wastes); parts of fruit and vegetables such as leaves, roots and toppings (that are removed as part of the processing for sale); or a mixture of the above, then the feedstock is considered a ‘by-product’ and not a ‘waste’.

As such, operators of these facilities ‘do not require an environmental permit or exemption either for the operation of the plant or for the beneficial use of the digestate produced’.

This will be only be the case, however, as long as all of the following apply:

• the by-products are not mixed with and do not contain any wastes;
• the by-products are suitable for use and certain to be used as a feedstock for AD (irrespective of whether the AD plant is on a farm or not);
• the feedstock can be used directly as an AD feedstock with no additional processing (apart from that which might be ‘reasonably expected’ of energy crops, for example, maceration); and
• the use of the crop residues in AD will not lead to ‘overall adverse environmental or human health impacts’ (i.e. the crop residues will need to be disease free). This also needs to take into account any storage and processing prior to AD, the AD process itself, as well as the subsequent storage and use of the biogas and digestate produced.

Any operators holding waste permits that currently run AD plants fulfilling this criteria, and that ‘do not wish to ever take any waste feedstocks in the future’, may thus consider surrendering their plant permit and/or landscaping permit.

However, AD plants that utilise feedstock containing waste (i.e. surplus or rejected fruit and vegetables from supermarkets and restaurants), will still require an environmental permit or exemption.

The EA added, however, that it had been ‘discussing the environmental risks associated with all AD facilities with Defra [the Department for Environment, Food & Rural Affairs]’, and that it has ‘recommended to them that consideration be given to the case for regulating AD under the Environmental Permitting Regulations irrespective of the feedstock used’.

Industry welcomes the change

The move has been welcomed by the Renewable Energy Association (REA), which had written to then Secretary of State for Farming & Rural Affairs Owen Paterson earlier this year about ‘resolving [the] technical regulatory issue, which presents a significant barrier to the use of commercial processing rejects and farm residues in on-farm and on-site anaerobic digestion facilities’.

REA Technical Director Jeremy Jacobs said: “This regulatory boost will be the final piece in the puzzle for several on-site and on-farm AD projects that had been hanging in the balance, which is great news.”

Branston Ltd, a potato producer and member of the REA, welcomed the change, with Vidyanath Gururajan, Innovations Director, saying: “This is definitely a step in the right direction for encouraging the fresh produce industry to use AD technology to reduce its carbon emissions.

“I sincerely thank the REA for taking up this subject and seeing it through with Environment Agency. We look forward to seeing this guidance implemented consistently across the UK.”

Jacobs added that he hoped political parties would address the ‘Feed-in Tariff [FiT] problem’, in which FiTs currently count towards capacity triggers at the time of registration, rather than the time the plant comes online. The REA has previously argued that his make AD ‘uneconomical for farmers even though hardly any on-farm plants have been built’.

Jacobs said: “As the election nears, we’re encouraging all parties to commit to a genuine and lasting solution to the FIT problem when it is reviewed in 2015. This will unlock AD’s full potential for creating much needed green jobs and growth in the rural economy, as well as producing sustainable fertiliser, green gas and electricity to reduce our dependence on fossil fuels.”

Read the Environment Agency’s briefing note on crop residues in AD or the REA’s letter to Owen Paterson.