This week the Department for Energy and Climate Change (DECC) launched a consultation on  subsidy payments for crop-fed anaerobic digesters. The use of energy crops - most prominently maize - in generating renewable electricity has seen production boom in recent years. In the UK, the maize area has doubled since 2000, increasing from 100,00ha 16 years ago to 190,000ha today.

Although large farm unions have got behind the idea of growing feedstocks, environmentalists and sustainable food groups have questioned the green credentials of the method and warned that growing energy crops risks shifting food production onto new land (indirect land use change) or contributing to volatility in food prices. Campaigners have also claimed that maize is being subsidised twice, once for farmers who grow the crop and again for the AD plant owners who use it to generate energy.

The government has also sought to cut back on subsidising measures that could compete with food production. In October 2014, Defra announced cuts to farm payments for land with large-scale solar installations, ostensibly this cut served to “Removing one of the incentives to use land that could be used for either growing crops, animals or food.”

In the case of its AD review, DECC reiterated that “It is… Government policy that the primary purpose of agricultural land should be for growing food” but that “Data published at the end of 2015 suggests maize is increasingly being grown for AD installations.”

The consultation suggests that waste-fed AD plants tend to offer the greatest greenhouse gas emissions savings by putting to use products that would otherwise be a major source of greenhouse gasses (food waste, farm waste, unusable agricultural crop residues). DECC pointed out, “In the core FITs [Feed In Tarrifs] Review consultation in 2015, we highlighted concerns that the increased use of crops posed risks to Government aims for AD regarding objectives on waste
management and low carbon energy.”  

DECC is proposing two measures; introducing sustainability criteria for land on which maize destined for AD plants can be grown, and cutting Feed-In Tariffs for crop-fed digesters, whilst preserving subsidies for waste-fed AD operations.

The NFU reacted strongly to the launch of the consultation on Friday, and said it will make a “Robust response” to the consultation.

The union’s renewable energy advisor Dr Jonathan Scurlock said, “Yet again, this Government seems determined to throttle the life out of the emerging renewable energy market. After slashing support for the growing solar and biomass industries, this seems like the unkindest cut of all.  The multiple environmental and soil management benefits from widespread deployment of on-farm AD will be lost, including the huge potential for avoiding farmyard methane emissions from manure and slurry – a bit of an own-goal for DECC, given that this is a powerful greenhouse gas.”

Dr Scurlock continued, “The NFU also has serious reservations about the practicability of quarterly reporting of feedstock sustainability and the proposed maximum threshold for inclusion of crop feedstocks. This is bad news for the rural economy, and bad for agricultural efforts to tackle climate change.”

However, the Soil Association’s policy officer Georgia Farnworth said the Association has been calling for similar measures to be implemented, and that SA’s ‘Runaway Maize’ report, published last year, highlighted the environmental impacts of increases in maize production. Speaking to Farming Online on Friday, Farnworth said, “We’re delighted to see that the government is taking note of one of the issues that we’ve been campaigning on for so long.”

The Soil Association has stressed that it supports green energy that is “genuinely renewable,” such as producing energy from waste and using AD as part of a closed system, but insists that crop-fed systems aren’t sustainable. Speaking to the BBC on Wednesday, Georgia Farnworth said, “Maize is heavily subsidised and is occupying land that should be used for food crops. [The Soil Association’s recent] research concludes that any greenhouse gas savings derived from maize were offset by the considerable environmental damage that this crop can cause.”

The Soil Association policy officer said the DECC consultation is supported by the findings of the government Environmental Audit Committee’s report on soil health, which was published last week. The report notes “Maize production can damage soil health when managed incorrectly, and incentives for anaerobic digestion should be structured to reflect this. The double subsidy for maize produced for anaerobic digestion is counterproductive and has contributed to the increase in land used for maize production.”