Understanding the Benefits of Biogas for Farmers

Posted by Clare Burns on 13-Oct-2015 11:11:13

Creating energy from your waste has proven environmental, economic and social benefits.

More than one in three farmers (38%) have already invested in renewable energy, whilst 61% say they are likely to between now and 2018. This is according to survey statistics published by Farmers Weekly in 2013.

Since then it’s  fair to say that this number has increased as more farmers see the benefits renewable energy can bring to their business. As the National Farmers’ Union (NFU) has previously suggested: “Small-scale renewables don’t just produce energy, they’re an essential way for Britain’s farmers to earn a reliable income in a time of volatile food prices, and so keep farming and the wider rural economy afloat.” 

However, the percentage of farmers who say they are likely in invest in the future may well have dropped quite significantly of late thanks to uncertainty created by the ongoing review of the renewable energy incentive schemes. 

Unpredictable forecast

In August, the Government published proposals that, if implemented, will see some solar and wind subsidies through the Feed-in Tariff (FiT) cut by 87% and 58% respectively. To a certain extent, the proposed changes also affect anaerobic digestion (AD)  – a process through which organic farm waste is converted into electricity, heat and fertiliser. The government is also rumoured to be reviewing other subsidy regimes, such as the Renewable Heat Incentive (RHI). 

It’s no surprise that this hasn’t gone down well in the farming community. There is a consultation underway and pressure is increasing on the government to reassess its review of FiTs. But with solar and wind firmly in the firing line, anaerobic digestion could actually come to the fore. 

Increasingly popular

AD technology has been around for some time, but has previously  received less attention than its solar and wind cousins. This all changed in 2010 with the coalition government’s commitment to this approach to energy production. 

Since then AD has been supported by the government with grants to help farmers undertake feasibility studies and loans to offset the higher upfront capital costs. The planning regime is also often less arduous than for, say, a medium-sized wind turbine. 

Within this context, there are currently 102 farm-fed plants in the UK and 156 plants using agricultural waste for AD  in the development pipeline. The NFU wants to see this hit 1,000 within the next five years. 

Dairy farmers are particularly keen on the concept. It’s hardly surprising given that, (a) they have a lot of slurry to dispose of and, (b) the milk price crisis is forcing them to look at ways to improve efficiencies and seek out other revenue streams. AD ticks both boxes. 

Energy security

For a start, the waste disposal costs are minimised: slurry is fed into the digester along with a proportion of dry energy crops and this mixture is turned into biogas, which can be collected and used to generate electricity and heat using Combined Heat & Power (CHP). This can be used to power milking parlours, or heat poultry sheds and farm buildings, with energy bills significantly reduced. 

In fact, some farms can become self-sufficient in energy production and even sell surpluses to the grid. Although this can be expensive currently, there are moves to improve the process and reduce costs. 

Creating this green energy attracts the subsidies mentioned above – and if CHP is used then there’s the possibility to claim both RHI and FiTs. An additional saving is the digestate, which can be used or sold as an organic fertiliser that improves soil condition and ensures nutrients are recycled on the farm rather than lost. 

Money well spent

In addition, there are environmental benefits. The  management of slurry through AD reduces emissions of methane – a greenhouse gas that’s 23 times more harmful to the environment than carbon dioxide. 

A recent project by the Renewable Energy Association showed the extent to which AD can be a cost-effective way to reduce greenhouse gas emissions. With the government questioning whether subsidies for green energy are too high, this study showed how AD can punch above its weight and offer value for taxpayers’ money. 

With the consultation on a review of the Feed-in Tariffs scheme due to run until 23 October, the jury is out to decide the precise future of on-farm renewable energy. But what is certain, anaerobic digestion has proved its worth and the benefits of biogas for farmers are clear to see. 


  • Over a third of farmers have invested in renewable energy so far and the number is rising.

  • Solar, wind and anaerobic digestion (AD) are some of the most popular approaches.

  • Farms that produce significant quantities of slurry will find AD a cost-effective route.

  • Reduced greenhouse gas emissions and energy security are significant benefits.

  • The Feed-in Tariffs framework is under review, but renewable energy is so embedded in farm life, it has potential to withstand any changes in subsidies.

Looking to introduce renewable energy production on your farm to reduce costs and generate new revenue?

The Farmer's Guide to Renewable Energy

Topics: Farming

Clare Burns

Clare Burns is a technical marketer with many years’ experience in the energy arena, as well as in fashion, telecoms and education. Fluent in 3 languages, Clare has worked across Europe. She currently works for ENER-G, a UK manufacturer of carbon reducing, energy efficient products exporting its cogeneration technology across the globe.