Brain’s Farm near Wincanton is producing biomethane and preparing to supply digestate back to farms, completing a truly circular energy cycle

It is predicted that, by 2030, more than ten per cent of the gas that we use in the UK could be biomethane – a renewable energy that is created by anaerobic digesters (AD). The figures, suggested by the Anaerobic Digestion and Bioresources Association, state that with new efficiency improvements, 8 billion cubic metres of the gas could be used in our homes.
One local contributor to the uplift in biomethane gas is the newly-converted Brain’s Farm near Wincanton. Planning permission was granted in 2017 for the site of the once-productive dairy farm to transition to renewable gas production. The plant is currently in the commissioning and ramping-up stage – meaning that while not yet at full production, the plant is operational.
James Lloyd, founder of BioWatt, the company that oversees the operation of the site, explained more about the project to The BV: ‘We are producing gas, but currently everything is in the performance testing phase. So, we’re going through all the equipment that has been installed as part of the construction project.’
A virtuous contributor
AD plants work by creating two products by digesting organic matter – biogas (used for heating or electricity) and digestate (the leftover solids and liquids in the tanks that is nutrient-rich and makes a great organic fertiliser).
At Brain’s Farm, as it is still early days, there is currently no digestate being produced. ‘It’s a two-tank process,’ said James. ’The first tank is fed, and in doing so it flows into the second tank. So, the second tank is now coming up to being at its operating level. Once it reaches that, then we’ll start to commission and performance test the digestate separation, and then we’ll be into producing digestate.’
Once that digestate is being produced, it will go back to the farmers who have contracts to grow feedstock for the plant – it will be spread across the fields to help improve the harvest for the following year’s feedstock.
‘We’ve had a lot of interest in taking the digestate – there’s a history of AD plants in the area, so the actual use of digestate and its benefits seems to be quite well known. As a result, we’ve had quite a bit of contact with local farmers inquiring as to whether it is available. Obviously, at this stage, the first digestate produced will be connected to those farmers who are growing for us.’
Digestate is a popular commodity. It’s cheaper than traditional fertiliser, but, more importantly, it removes the need for the creation of synthetic fertilisers, which are energy-intensive to create and rely on fossil fuels.
For now, the AD plant will only be fed on locally-grown crops, but soon it will be able to create biogas from other agriculture byproducts.
‘Right now we’re just commissioning on crop [products],’ says James. ‘The main reason being it’s a very safe way of starting the plant up. There’s no variability, so we’re not worried about contamination. When you’re testing everything, you take a variable out of the risk metric. So if you’re not worried about your feedstock, you can focus entirely on testing the equipment.
‘We are waiting for our environmental permit. As soon as we’ve got that, we’ll be allowed to take manures as feedstock.
‘Crops give you the best consistency of gas fuel from AD. But if you’re assuming the purpose of AD is to be a virtuous contributor to renewable energy at the lowest possible carbon cost, then what you should be processing are byproducts that haven’t got any other use … so, things like manures, straws and other agricultural byproducts.’

Objection
Even though Brain’s Farm is good for the environment, creates jobs for the local economy and revenue for local farmers, the AD came amid some concern from the residents of the area.
In 2017, Wincanton Town Council initially recommended the application be rejected, citing increased traffic and the ‘inappropriate development in the flood plain’. Local farmers believed that it would increase the cost of agricultural land to rent, making it harder for new farmers to acquire land and join the industry.
That same year, Horsington Parish Council ejected to the proposal on the grounds it was too large and inappropriate for the location and that it would have a visual impact on the rural landscape.
The communities of Buckhorn Weston and Kingston Magna (BWKM) were so concerned about the potential traffic impacts of the AD plant on their small country villages that they formed a community action group. Chairman of the BWKM Community Action Group, John Grant told The BV BioWatt had been very open: ‘I can’t say that we’ve always agreed about everything, but they’ve been very open to dialogue, and once discussions have taken place, we’ve made progress on our concerns.
‘What they’ve explained to us is that there will be some periods over this year when there will be [crop] deliveries taking place. That’s the period when, if there were going to be any traffic problems, these would occur.’
The collaboration between the action group and BioWatt led Somerset Council to approve a vehicle routing and signage strategy (VRSS) which means only farmers based in Buckhorn Weston and Kingston Magna are permitted to drive through those villages to the AD plant. The road signage directs all other AD traffic to the A303 via Wincanton. James Lloyd told the BV how the plant was to manage the traffic going in and out of the site at busy periods: ‘I think the fear of these things is considerably greater than the reality. We did a full harvest last year for grass, whole crop and maize – 13,000 tons of crop delivered to the site. And we had one errant driver.’
Harvest signs
‘I think, generally speaking, people have got a high degree of concern locally because of the general tractor use in the area. But actually, when you compare it to the number of vehicles already on the road, it will barely register. If we didn’t publish the harvest, there’s a fair chance people wouldn’t even notice.
‘We have created what we hope is a strong system to ensure the drivers all stick to the VRSS. Before harvest gets under way, we have an induction with all the drivers where we explain the importance of sticking to the prescribed routes. Each tractor and trailer is awarded a Harvest Sign, similar to a licence badge, which sits on the tractor and they hand back at the end of harvest. If someone rings with a complaint, we can know who the driver of that tractor and trailer is: next time they come onto the site, we’ll explain what’s happened and give them a warning. Second warning, they’ll be asked to stop for the day, and they’ll be fully re-inducted. And then, if there’s a third warning, it’s a case of “You have obviously chosen to disregard rules”, in which case we won’t be allowing them back on site.’