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Fre-energy Ltd

Fre-energy specialises in anaerobic digestion and associated technologies. An established, innovative designer of on-farm anaerobic digestion systems, based in north-east Wales, we pride ourselves in providing bespoke technological solutions for the management of on-farm wastes, tailoring our installations to meet the specific needs of each agricultural setting to complement our clients core farm business. Our aim is to create an on-farm circular economy where farm wastes are used to fuel the digester thereby producing useable energy for onfarm/local use and a high-quality nutrient-rich digestate used as a soil conditioner to optimise crop growth. We passionately believe that an on-farm AD facility is about environmentally positive and sustainable agriculture rather than a farm becoming a rural power station.

The robustness of our design and flexibility of our system enables Fre-energy AD plants to routinely process a wide range of farm wastes. For example, slurries and manures, FYM, silage, chicken litter, through to abattoir arisings, food processing and manufacturing and hospitality waste. The ability to process such a varied range of materials allows the operator the flexibility to co-digest ‘opportunist’ wastes as they become available. Running an AD plant on farm wastes does not require a great deal of reskilling; stock farmers already have an informed grasp of the underpinning science of anaerobic digestion – it is, after all, basically a steel or concrete rumen.

All Fre-energy plants are fitted with our unique patented combined de-gritting with sequential gas-actuated mixing technology and foam alleviation system as standard. The de-gritting technology is designed to manage grit-laden, slurries without the worry of having to schedule in costly down-time to de-silt the digester tank. Gas mixing serves to provide a low parasitic load, therefore increases the operational energy efficiency of the plant. The foam alleviation system enables co-digestion of high-strength feedstocks without compromising the operational process capacity.

We have built 12 plants around the UK ranging from 80kW to 500kW and each plant consistently demonstrates high rates of performance and efficiency. As part of our comprehensive customer service, we provide 12-months support post commissioning and offer the availability of an ongoing remote monitoring service to provide peace of mind regarding plant performance. While we specialise in feasibility, feedstock evaluation, AD design, construction and commissioning we can also assist geotechnical surveys and permitting arrangements.

At Fre-energy we are firmly committed to the economic, environmental, and social benefits of farm waste AD plants and believe they should be recognised and established as a standard item of the agricultural equipment necessary to operate a successful farm business.


  • Bespoke client consultation: we believe it is crucial to size a potential AD installation to suit the clients’ requirements.
  • Identifying Inputs and the Outputs: to ensure there are readily available feedstocks in terms of both quality and quantity, land availability for spreading the digestate, and uses for the energy generated.
  • Tailored AD design: from the initial consultation we work up a design to match the unique agricultural setting to include feasibility study, full design, manufacture, and construction of anaerobic digestion plants.
  • Commissioning and operator training: Our technical engineers commission our installations and closely monitors and advises on the operational processes to secure optimum bacterial health in the AD tank.
  • Follow-up support: we support the plant operator for a 12-month period post commissioning and are readily available with advice and guidance.
  • On-going: we offer the client the opportunity to set up a bespoke technical support agreement with Fre-energy which comprises a remote monitoring service together with periodic site visits if require.
  • Remedial works on non Fre-energy AD sites to reactivate failed plants
  • Bespoke Control Systems
  • Collaborative gas to grid projects



  • Patented combined de-gritting with sequential gas actuated mixing technology provides low-energy, inprocess grit removal to maintain optimum operational capacity and eliminate the need to shut down generation to desilt the digester tank.
  • Efficient low energy gas mixing system operates a very low parasitic load. The energy used to mix the digester with the recirculated gas is a fraction of that used in a mechanically mixed system.
  • Integrated foam alleviation enables co-digestion of a broad range of inputs and to process shock loads of high strength feedstocks containing fats and sugars that are prone to causing acid indigestion. Removing the foam allows the bacteria to recover quickly to optimum gas production.
  • Unique fibreglass insulated tank roof to minimise heat loss – heat lost is heat not available for other uses.
  • All serviceable parts are external to the gas space to maximise operator safety.
  • Remote monitoring technology to help maintain plant efficiency.
  • 24-hour text base alert system on critical plant components.

Contact Fre-energy Ltd

Company Details

Fre-energy Ltd

Lodge Farm

Commonwood Holt


LL13 9TE


Tel: 01829 270397 Email: Website: