Anaerobic Digester Design Specialists with a focus on Plug Flow Technology for On-Farm AD plants
View our latest projects...including a first in the UK of it's kind!

About Lutra

Who we are and what we offer

About us

Lutra lutra – meaning ‘European otter’

Established in April 2014 and based alongside the River Teme, Lutra Limited is pioneering a new methodology for AD project management and design.

Director Michael Chesshire pioneered AD in the UK, and remains a prominent name in the industry today. Michael brings years of experience to Lutra and maintains his focus on design improvement and project specification. Working in partnership and alongside Michael for many years, Phil Greenaway is a central part of Lutra focusing on Business Development and Project Management.

Our on-site plant BMAD (you don’t have to be…but it helps!) uses AD technology to recycle food waste and compostable materials such as cardboard, into energy and fertiliser on a small local scale. A fully working AD plant on site enables us to discuss, plan, and show you the potential benefits of a suitably sized AD plant with physical examples to support detailed planning.

Our services

Lutra is able to offer either a complete project management package, design and commissioning service or a design service only.

Design includes the preparation of process calculations, economic assessment, process drawings, general arrangement drawings, detailed mechanical and electrical drawings, equipment specification, process control and O&M manuals. Lutra is able to take on the role of Principal Designer under CDM.

Project management includes the preparation of the project Gantt chart, which is updated monthly, the preparation of monthly reports including forecast cost estimates, the preparation of purchase orders on behalf of the client, the chairing of monthly progress meetings and the preparation of meeting minutes.

Clients have the flexibility to determine the level of their involvement and their input in their project. They can influence the design of their AD plant or simply leave it all to Lutra’s experienced team.

With Lutra taking responsibility for all the procurement but with the client paying suppliers direct, the client is able to control the finances and to benefit from complete transparency of the project costs.

This provides them with the knowledge that not only do they have the optimal design for their project they also have the most economical solution.

Our Team

Together Everyone Achieves More.

Michael Chesshire


Michael is a Cambridge engineering graduate who, after a short time in the nuclear industry, set up his first AD business Farmgas at the age of 22. Since then he has established himself as one of the UK’s leading experts in AD building over 140 AD plants, from 50kW to 1.5MW, including pioneering the AD of food waste in the DEFRA demonstration plant at Ludlow during his ownership of Greenfinch. He continues to run his own AD plant ‘BMAD’ from home on locally collected food waste.

Michael has been a board member of the REA for 7 years and for the past year has acted as Chair of the Policy Board. A visiting professor at the University of Southampton, Michael remains influential within the industry at an education level, an advisory level and on the ground with the on-going development of his small scale plug flow system.

Phil Greenaway

Business Development

Phil is entering his 10th year in AD and leads the project management and business development sides of the business. Phil has an in depth knowledge of Anaerobic Digestion process, but with the ability to translate this information to the client in user friendly terms.

He successfully managed the build of one of the UK’s first plug flow digesters in Northamptonshire from the first spade in the ground through to the final stage of commissioning. In his days with BiogenGreenfinch he led the bid team, with Michael as his technical lead, which was successful in winning 3 out of the 6 Welsh Assembly AD projects.

Phil has won over 25 contracts for the innovative plug flow system and continues to grow the business whilst managing the Company’s current projects.

Justin Parry

Commissioning Engineer

Heather Mason

Office Manager

Heather manages the administrative side of Lutra and is your first point of contact in our offices at Barrett’s Mill.

With a degree in Geography (BA Hons) from Aberystwyth University she has worked as a head receptionist and in business banking prior to joining Lutra. Heather's role includes the day-to-day running of the offices, assisting with the monitoring of the on site AD plant BMAD and liaising with local producers of food waste. She is continuing to increase her knowledge of AD with a focus on elements of CDM during the pre-construction and construction phases whilst assisting with scheduling and procurement.

Available daily to answer or forward email enquiries, Heather is office based Monday 8:45-2:30, Wednesday 8:45-4:45 and Friday 8:45-2:30.

Martin Aplin

CAD Draughtsman

Martin is our CAD draughtsman, preparing 3D models and layouts for customer approval, and also detailed drawings for costings and for production.

He has many years experience in both production and development engineering, working in various types of industry.

Edmund Khoo


Edmund was our summer intern, recently graduating from University College London with a Chemical Engineering (BEng) degree. Following his time at Lutra, Edmund intends to continue his Chemical Engineering (MEng) programme at UCL.

Whilst interning at Lutra, Edmund’s main focus was to gain first-hand experience in the contracting industry and project management, as well as familiarising himself with the anaerobic digester systems specialised at Lutra. Edmund also integrated engineering knowledge from his degree with critical thinking and analysing skills to provide effective solutions for complex problems. Edmund achieved his goals by being directly involved with the commissioning of various projects and operation of the BMAD system during his internship with Lutra.

What We Do

AD Consultancy

Lutra provides clients with the design and project management of AD plants with site and user specific variables taken into account throughout the project. Lutra is keen to engage and involve clients in their build to a level to suit them individually. Commitment to the use of familiar trades people where appropriate alongside established industry specialists ensures the highest quality build and successful project delivery. A focus on small scale, farm based AD and community led AD projects are the areas in which Lutra excels, providing accessible planning, high quality design and cost effective completion.

Plug flow technology – Lutra’s preferred plug flow design provides the optimum hydraulic residence time (the time allowed for the conversion of the organic dry matter to biogas) ensuring that the micro-organisms are given enough time to complete their natural process. This is considered to be the most effective method of digestion, particularly for smaller scale plants, and maximises the financial returns for our clients.

Food Waste AD

Lutra has built its own small scale plug flow digester for food waste at its premises near Ludlow and we are working with local businesses and festivals to collect and process food waste and compostable materials. Removing unnecessary food waste transport and preventing resources going to landfill, local AD can turn waste into renewable energy, and to a project specific scale and capacity. Ongoing research explores the limitations of small scale AD monitoring feed stock variables and subsequent outputs. If you are locally based we can offer food waste collections to suit your business needs, be it weekly, twice-weekly, monthly or even one-off events we are here to help.

Its pioneering technology and scale provides an ideal model for small community and commercial plants between 20 and 50kW.



Examples of our AD plants


Our AD plant - food waste recycling

Ballingham Court Farm

Our Herefordshire project - a UK first!

Welham Bridge West Farm

Our Yorkshire Project

Gelligarneddau Farm

Our Lampeter Project

Mickram - Kings Lynn

Signed agreement, subject to planning permission, for a 1MW plug-flow digester

Contact Us

Please forward your enquiry via the form below, by email to or call us on 01584 711659

Find US

Barrett’s Mill, Ludlow, Shropshire, SY8 4AH

01584 711659

Please ignore your SatNav and use the map provided.

Travelling South on the A49 towards Leominster, as you come over the skewed railway bridge we are the next left, down a farm track. If you reach The Salwey Arms you've gone too far.

Travelling North on the A49 towards Ludlow, as you pass The Salwey Arms, the road bares right handed as indicated by chevrons, just around that corner turn right down the farm track. If you cross the skewed railway bridge you've gone too far and it is safest to turn around at the lay-by at Ashford Bowdler.

Leaving Lutra - it is suggested for safety reasons that when leaving Lutra, regardless of your route, that you turn left and head South on the A49 initially. It is easy to subsequently turn around to head North and much safer due to the restricted view when pulling out of the junction.