We are excited to announce that we have been shortlisted for Business Leader’s Green Business of the Year award. We are grateful that our work in sustainability is being recognised.

What is anaerobic digestion?

Anaerobic digestion (AD) is a method of producing renewable energy from the ‘digestion’ of blended ‘feedstock’ materials. These feedstocks will typically be taken from sources including livestock waste products, energy crops, and residues and wastes from food production.

Each AD plant has a specific ‘menu’ of feedstocks, developed according to availability of the feedstock materials, size of plant and target gas output. These are fed into sealed tanks (known as digesters) daily, where naturally occurring micro-organisms and bacteria get to work with the input of heat and constant stirring. The resulting biogas is syphoned off into storage domes. This is then either fed into Combined Heat and Power Units (CHPs) to create electricity and heat, or injected into the National Grid as green gas. The remaining bi-product after the gas has been extracted is known as digestate. This is an excellent replacement for animal manures and artificial fertilisers in crop production, thus creating a sustainable lifecycle.

Our green impact

By specialising in AD, we are able to provide:

  • the identification, testing and incorporation of the latest technology
  • the best-in-class management of sourcing, delivery and use within the AD system of feedstock and the resulting digestate
  • industry leading site operations teams and control systems.

Net zero and the circular economy

Each step of AD’s biological process gives something back to the businesses we work with, the communities around us, the economy, and the environment. We are also committed to reaching net zero via renewable energy production and supporting associated businesses to reduce their carbon footprint, as well as reducing our own.

The very essence of anaerobic digestion is its’ circular nature. Unlike many other forms of renewable energy, the process of AD provides a wide range of sustainable outputs. For example, the biogas produced provides a renewable gas source, which is supplied into the National Grid as either green gas or electricity via direct links on our plants.

As well as being exported to the grid, the electricity and heat produced by our CHPs is used in the operation of AD plants and offices and it’s used directly in the operation of businesses adjacent to the AD sites. Examples include:

  • business parks
  • dairy units
  • poultry production
  • woodchip drying.

Supporting local businesses and communities

We ensure that our feedstock providers are paid fair, guaranteed, and consistent prices for the feedstock they supply to AD plants, allowing them to diversify and offering protection from the fluctuations in commodity markets.  Anaerobic digestion generates local employment, both at the facilities and within local communities (including managing feedstock production, digestate distribution and maintenance services).

We work tirelessly to ensure minimal wastage at every stage of our process. Our sites are located as close as possible to the sources of feedstock, primarily on farms, to minimise transport miles and wastage. A key part of the agreements in place with feedstock suppliers is the return to the land of the digestate produced from the AD process to ensure that the climate benefits are maximised. Since they do not possess fossil fuel, these renewable ‘biofertilisers’ ensure a reduction in agricultural carbon footprint.  The process on some of our sites use feedstock that would otherwise end up as landfill waste.

We also recognise that healthy soils encourage better plant growth which in turn sequesters more carbon. Therefore, we encourage our partner farms to adopt practices that incorporate what is best for soil health, including: avoiding soil compaction, incorporating grazing in rotations, improving soil fertility (with digestate) and multispecies cropping on field margins.

Our progress

Our initial target of operating with Green House Gas (GHG) emissions at least 60% below the EU fossil fuel average for heat has already been achieved. We currently operate with GHG at approximately 76% below the EU fossil fuel average. These figures do not include the carbon reduction resulting from the use of our digestate (as opposed to artificial fertilisers) to grow crops, so, in real terms, our GHG savings are even greater.

We use our experience to benefit other AD businesses by helping them to identify how they can improve their operations to provide increased environmental and financial returns and to identify the feasibility, suitability, economic advantages and key requirements of new AD facilities.

Through our proactive engagement with Ofgem we have also made suggestions that have been incorporated into new subsidy regimes. We are heavily involved in the consultation for the new Green Gas Support Scheme and will be beta testing the new scheme web platform with Ofgem.

To find out more about our work, please contact us today.