Farmers considering anaerobic digestion (AD) plants are finding themselves under pressure to increase the amount of waste feedstock and limit the amount of crops they use in the process following the publication of new Government recommendations.
The paper, recently released by the Department of Energy and Climate Change (DECC), discusses proposed reforms to the Renewable Heat Incentive (RHI) and acknowledges the ‘significant’ portion of plants geared towards high crop use.
In 2014, maize grown for AD made up 19 per cent of the total maize area in England and 0.7 per cent of England’s total arable area.
“The Government recognises there may be circumstances where developers find it preferable to use crops,” the DECC report says.
“These include operational reasons to increase the consistency and calorific value of the feedstock, or commercial reasons where the high biogas yield compensates for the costs of production, or to offset the risk of other feedstock supply, or when crops are not able to be sold to the food market.
“So while it may not be appropriate to ban crops from AD plants, it is not Government’s intention to drive an industry which has a high dependency on crops.”
In order to maximise the benefits of payments to contribute to carbon budgets the department has proposed measures to reduce or eliminate support for new installations relying on crops as their primary feedstock, which may also affect existing installations seeking to accredit/register additional capacity.
Gary Hague, business development director at Peak District based installer Regional Energy, says the shift in Government policy has opened up more opportunities for slurry based, smaller scale AD plants, which use little, if any crop-based feedstock.
“The AD sector has been dominated by the big systems as the bigger you make it, the bigger your return,” says Mr Hague.
“But to make the larger projects stack up you need feedstock and for that you need maize – but that contradicts why the systems were set up years ago, because you are growing food for fuel. The original systems were set up to use waste and then spread the nutrient rich digestate on crops. These plants would match the size of the farm.”
Charlotte Morton, chief executive of the Anaerobic Digestion and Bioresources Association (ADBA), says while farmers are being encouraged to assess projects based on the impact a plant can make on a farm’s self-sufficiency, including energy production and slurry management, the industry’s growth prospects are under serious threat from the tariff cuts to RHI tariff degressions and the halving of support under the Feed-in Tariff (FiT) Scheme.
“In addition to reduced funding support, Government is consulting on the parameters of an RHI budget cap, having already substantially curtailed industry growth by implementing a FiT cap at the ridiculously low deployment level of just 5MW per quarter – an allowance which has already been exhausted for the entire year,” says Ms Morton.
“Under these circumstances small-scale AD will struggle to be commercially viable with the result that, while there are considerable opportunities for farmers to join the surge in larger scale on-farm biomethane projects, many farmers will be left unable to benefit from the technology’s contribution towards: reversing soil degradation; reducing imported energy and fertiliser costs; increasing food production; tackling agricultural carbon emissions; and improving farm resilience.”
ADBA has been lobbying for parliamentary support for small-scale AD, including through greater recognition of the non-energy benefits which on-farm AD operators contribute.