The Fertilizer Association of Ireland’s 2024 study tour headed north this year to explore the anaerobic digestion sector, the region’s manure management challenges, and the practical solutions being implemented on the ground.
The first stop was a visit to dairy farmer Alastair Taylor in Ballymoney, Antrim. This is a busy 450ac farm, running a 280-cow indoor dairy herd with four Lely robotic milking machines and a Vector system, two broiler houses and an anaerobic digestion (AD) plant.
While there is lots going on there, the farm integrates seamlessly, with each enterprise complementing the others. It stands as one of the best examples of how an on-farm AD plant can help improve farm nutrient management and the commercial viability of the farm enterprises, all while maintaining its own commercial sustainability.
Dairy
Alastair milks 280 cows on his farm, using four Lely robotic milkers, with each cow being milked three times daily. The Norwegian Red, Montbéliarde and Holstein cross-bred cows are housed indoors throughout the year, each producing an average of 10,500 litres of milk annually. They are fed an average of 3.5 tonnes of concentrates per year, with the milk’s butterfat content averaging 4.5% and protein at 3.4%. He operates a four-cut silage system, with the fourth cut typically used as AD feedstock.
Alastair Taylor
He calves all year-round, with approximately 24 calves born each month. This system improves labour efficiency on the farm he explained. Male calves are sold depending on the farm’s TB status, as he is not equipped to rear or finish them. Vets visit every few weeks, and hoof trimming is routinely done every 100 to 150 days. “If you stay on top of it, you halve the problems,” he said.
The parlour has two footbaths for hoof treatment. The farm’s slurry is scraped into a tank daily, which is then pumped to the digester, while parlour washings and foot treatment solutions are stored separately and spread on the land.
The farm makes all of their silage and handles the digestate themselves, and he also grows 80ac of wholecrop cereals for their cows. Five years ago, Alastair installed four Lely milking robots, each of which now milks around 8,000 litres per day. He switched from a 16-unit conventional herringbone parlour and hasn’t looked back. While there was nothing wrong with the parlour, the robots have allowed him to save on labour and increase capacity.
He milks 280 cows on his farm.
Two years ago, he also installed the Vector feeding system, which rendered his diet feeder obsolete. This required some reorganisation of the farmyard, including creating new entrances. His farm is well-suited for the Lely Vector, as the robots “don’t handle slopes over 5%,” he said. Fortunately, the entire yard is on flat ground.
Anaerobic digestion plant
Like most AD plants in Northern Ireland, Alastair’s plant produces biogas, which is combusted to generate electricity that is exported to the grid. The plant produces approximately 150kWh of electricity, which is supported under the Northern Ireland Renewables Obligation (NIRO) scheme.
Around 70% of this is exported to the grid, while 30% is used to power his energy-intensive farm, allowing him to do so at a fraction of the cost compared to importing electricity.
While most AD plants in Northern Ireland are 500kWh in capacity, he could only secure a grid connection for 150kWh. Built in 2014 at an original cost of £1 million, the original plant included a 1,500m³ primary digester and a 1,500m³ digestate storage tank.
Two years ago, he also installed the Vector feeding system.
Under the NIRO scheme, Alastair receives four Renewable Obligation Certificates (ROCs) for every kWh produced, which can be traded on the open market.
This scheme ensures a healthy electricity price, making the business case for farm-scale AD stack up – something not available in the Republic of Ireland.
He has 10 years left of the scheme on the plant.
The plant is fed daily with five tonnes of poultry manure, four tonnes of silage (generally the fourth cut), one tonne of farmyard manure and 48 cubic metres of fresh slurry, producing around 70m³ of biogas per hour.
The solid fraction of the digestate is exported tillage farms.
The dry feedstock is loaded into a hopper, macerated and mixed with digestate before being pumped into the plant. The feedstock remains in the tank for 35 days before being transferred to a storage tank. He is in the process of changing this system to double this retention time.
Interestingly, Alastair heats the digester material to 42°C by pumping it through a heat exchanger located outside the tank, rather than using internal heating coils, which is more common.
When asked about future plans for his plant, he said he would be interested in exploring the viability of biomethane production, which would require expanding the plant.
Poultry
Alastair also has two poultry houses on the farm, each housing around 18,000 broilers. The broilers are raised for Moy Park, which takes around 35 days per batch. He normally raises six-to-seven batches per year.
The cows are fed all year around with the Vector.
He uses straw pellets as bedding, which can later be fed into the AD plant. The surplus heat generated by the AD plant is used to heat the poultry houses, eliminating the need to purchase gas.
Why this works
Alastair explained that his AD plant is mostly supplied with his farm waste. The plant effectively acts as a nutrient management hub for the farm, enabling investment in expensive equipment like slurry separators to improve overall nutrient handling. On-site, the digestate is separated, with the phosphorus-rich solid fraction exported to tillage farmers, while most of the liquid fraction is used on the farm. He needs around 850ac of land to manage the digestate.
Despite the intensive and busy nature of the farmyard, the farm operates very efficiently.
Alastair and his father work full-time on the farm and they employ a full-time herdsman to manage for the dairy cows.
Cows are milked three times per day.
His farm serves as a Technology Demonstration Farm for CAFRE and they often host a Greenmount student. Alastair’s mum helps with the poultry business.
They handle all the farm work themselves, without contractors, running John Deere and Massey Ferguson tractors, along with a John Deere forage harvester. He also runs a 4,000g and 3,500g Redrock slurry tankers along with an umbilical system.
Although he runs a high-input dairy system, Alastair doesn’t necessarily see it that way, due to the other enterprises on his farm.
He said that the electricity required to run the dairy farm is supplied by the AD plant and is practically free, which alone saves him around 3p per litre of milk in cost.
Another big saving comes from reduced fertiliser costs; apart from applying about 27 units of CAN/ac after the first silage cut, he didn’t use any other chemical fertiliser this year.
His liquid digestate provides around 30 units of N, 35 units of K and four units of P per 1,000g, with most of the phosphorus found in the seperated solid fraction.
He was also able to secure a 40% grant for robotic milking machines, which helped reduce the initial £700,000 investment. The robotic feeding system also cost around £130,000, but when weighing up the cost of a tractor, diet feeder and labour, he decided the switch was worth it. A further significant saving comes from heating the poultry houses for free, thanks to the AD plant.
Though Alastair is modest about his farm, it requires a serious level of management, technical competence and attention to detail to run such an efficient and lean operation.
In short
Alastair runs a busy farm in Ballymoney, Antrim, milking 280 cows alongside his two chicken houses and AD plant.Around 70% of the electricty produced by the AD plant is exported to the grid. The AD plant helps Alastair manage the nutrients from his poultry and dairy cows. 
The Vector follows metal strips laid around the yard.
Five years ago, he installed four Lely milking robots.
He has two broiler houses, which were being cleaned on the day of the visit.
The CHP engine.
Alastair Taylor, Ballymoney Irish Fertiliser Association field trip 2024
The Fertilizer Association of Ireland’s 2024 study tour headed north this year to explore the anaerobic digestion sector, the region’s manure management challenges, and the practical solutions being implemented on the ground.
The first stop was a visit to dairy farmer Alastair Taylor in Ballymoney, Antrim. This is a busy 450ac farm, running a 280-cow indoor dairy herd with four Lely robotic milking machines and a Vector system, two broiler houses and an anaerobic digestion (AD) plant.
While there is lots going on there, the farm integrates seamlessly, with each enterprise complementing the others. It stands as one of the best examples of how an on-farm AD plant can help improve farm nutrient management and the commercial viability of the farm enterprises, all while maintaining its own commercial sustainability.
Dairy
Alastair milks 280 cows on his farm, using four Lely robotic milkers, with each cow being milked three times daily. The Norwegian Red, Montbéliarde and Holstein cross-bred cows are housed indoors throughout the year, each producing an average of 10,500 litres of milk annually. They are fed an average of 3.5 tonnes of concentrates per year, with the milk’s butterfat content averaging 4.5% and protein at 3.4%. He operates a four-cut silage system, with the fourth cut typically used as AD feedstock.
Alastair Taylor
He calves all year-round, with approximately 24 calves born each month. This system improves labour efficiency on the farm he explained. Male calves are sold depending on the farm’s TB status, as he is not equipped to rear or finish them. Vets visit every few weeks, and hoof trimming is routinely done every 100 to 150 days. “If you stay on top of it, you halve the problems,” he said.
The parlour has two footbaths for hoof treatment. The farm’s slurry is scraped into a tank daily, which is then pumped to the digester, while parlour washings and foot treatment solutions are stored separately and spread on the land.
The farm makes all of their silage and handles the digestate themselves, and he also grows 80ac of wholecrop cereals for their cows. Five years ago, Alastair installed four Lely milking robots, each of which now milks around 8,000 litres per day. He switched from a 16-unit conventional herringbone parlour and hasn’t looked back. While there was nothing wrong with the parlour, the robots have allowed him to save on labour and increase capacity.
He milks 280 cows on his farm.
Two years ago, he also installed the Vector feeding system, which rendered his diet feeder obsolete. This required some reorganisation of the farmyard, including creating new entrances. His farm is well-suited for the Lely Vector, as the robots “don’t handle slopes over 5%,” he said. Fortunately, the entire yard is on flat ground.
Anaerobic digestion plant
Like most AD plants in Northern Ireland, Alastair’s plant produces biogas, which is combusted to generate electricity that is exported to the grid. The plant produces approximately 150kWh of electricity, which is supported under the Northern Ireland Renewables Obligation (NIRO) scheme.
Around 70% of this is exported to the grid, while 30% is used to power his energy-intensive farm, allowing him to do so at a fraction of the cost compared to importing electricity.
While most AD plants in Northern Ireland are 500kWh in capacity, he could only secure a grid connection for 150kWh. Built in 2014 at an original cost of £1 million, the original plant included a 1,500m³ primary digester and a 1,500m³ digestate storage tank.
Two years ago, he also installed the Vector feeding system.
Under the NIRO scheme, Alastair receives four Renewable Obligation Certificates (ROCs) for every kWh produced, which can be traded on the open market.
This scheme ensures a healthy electricity price, making the business case for farm-scale AD stack up – something not available in the Republic of Ireland.
He has 10 years left of the scheme on the plant.
The plant is fed daily with five tonnes of poultry manure, four tonnes of silage (generally the fourth cut), one tonne of farmyard manure and 48 cubic metres of fresh slurry, producing around 70m³ of biogas per hour.
The solid fraction of the digestate is exported tillage farms.
The dry feedstock is loaded into a hopper, macerated and mixed with digestate before being pumped into the plant. The feedstock remains in the tank for 35 days before being transferred to a storage tank. He is in the process of changing this system to double this retention time.
Interestingly, Alastair heats the digester material to 42°C by pumping it through a heat exchanger located outside the tank, rather than using internal heating coils, which is more common.
When asked about future plans for his plant, he said he would be interested in exploring the viability of biomethane production, which would require expanding the plant.
Poultry
Alastair also has two poultry houses on the farm, each housing around 18,000 broilers. The broilers are raised for Moy Park, which takes around 35 days per batch. He normally raises six-to-seven batches per year.
The cows are fed all year around with the Vector.
He uses straw pellets as bedding, which can later be fed into the AD plant. The surplus heat generated by the AD plant is used to heat the poultry houses, eliminating the need to purchase gas.
Why this works
Alastair explained that his AD plant is mostly supplied with his farm waste. The plant effectively acts as a nutrient management hub for the farm, enabling investment in expensive equipment like slurry separators to improve overall nutrient handling. On-site, the digestate is separated, with the phosphorus-rich solid fraction exported to tillage farmers, while most of the liquid fraction is used on the farm. He needs around 850ac of land to manage the digestate.
Despite the intensive and busy nature of the farmyard, the farm operates very efficiently.
Alastair and his father work full-time on the farm and they employ a full-time herdsman to manage for the dairy cows.
Cows are milked three times per day.
His farm serves as a Technology Demonstration Farm for CAFRE and they often host a Greenmount student. Alastair’s mum helps with the poultry business.
They handle all the farm work themselves, without contractors, running John Deere and Massey Ferguson tractors, along with a John Deere forage harvester. He also runs a 4,000g and 3,500g Redrock slurry tankers along with an umbilical system.
Although he runs a high-input dairy system, Alastair doesn’t necessarily see it that way, due to the other enterprises on his farm.
He said that the electricity required to run the dairy farm is supplied by the AD plant and is practically free, which alone saves him around 3p per litre of milk in cost.
Another big saving comes from reduced fertiliser costs; apart from applying about 27 units of CAN/ac after the first silage cut, he didn’t use any other chemical fertiliser this year.
His liquid digestate provides around 30 units of N, 35 units of K and four units of P per 1,000g, with most of the phosphorus found in the seperated solid fraction.
He was also able to secure a 40% grant for robotic milking machines, which helped reduce the initial £700,000 investment. The robotic feeding system also cost around £130,000, but when weighing up the cost of a tractor, diet feeder and labour, he decided the switch was worth it. A further significant saving comes from heating the poultry houses for free, thanks to the AD plant.
Though Alastair is modest about his farm, it requires a serious level of management, technical competence and attention to detail to run such an efficient and lean operation.
In short
Alastair runs a busy farm in Ballymoney, Antrim, milking 280 cows alongside his two chicken houses and AD plant.Around 70% of the electricty produced by the AD plant is exported to the grid. The AD plant helps Alastair manage the nutrients from his poultry and dairy cows.
The Vector follows metal strips laid around the yard.
Five years ago, he installed four Lely milking robots.
He has two broiler houses, which were being cleaned on the day of the visit.
The CHP engine.
Alastair Taylor, Ballymoney Irish Fertiliser Association field trip 2024
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