A new high-welfare dairy in Wiltshire will not only be producing milk efficiently, but also renewable electricity and heat for the local school and leisure centre.
Following a comprehensive review of milk production, Stowell Farms, decided to invest in a modern, 500-cow unit, complete with an AD (anaerobic digestion) plant at Sharcott Pennings Farm, near Pewsey.
Despite 14 dairy farmers quitting the industry each week and 1 million litres of fresh milk being imported into the UK every day, it was felt there was a future for milk production on the 3,000 acre (1200 ha) estate, but the existing dairy at East Stowell was no longer viable. The new dairy will incorporate 75 per cent cubicle and 25 per cent straw yard housing with modern milking and handling facilities.
The biogas plant, currently being installed by EnviTec Biogas UK Ltd, was seen as a means of adding value to the project by making use of the cow slurry, and reducing pollution and smell, in addition to producing ’green’ energy. It is estimated that the field application of the digestate alone will save the farm over 400 tonnes of manufactured fertiliser worth £140,000 at current prices.
Some 500 of the farms’ 1850 (750 ha) arable acres will be used to produce maize and whole-crop silage to feed the digester which will produce 4,150,000 kWh of electricity, some of which will be used on the farm. The surplus will be sold into the National Grid at 13p per kWh in addition to the retail electricity price, currently guaranteed at just over 3p per kWh. The plant will also be producing 3,555,000 kWh of surplus heat, which it is hoped will benefit the local community. Thermal energy, in the form of hot water will be offered at a competitive price to the nearby school and leisure centre, after being pumped from the farm site through an insulated pipe.
The biogas plant, installed by a German team using proven technology, is expected to be producing electricity by late summer having started in February. It cost around £2 million.
"When the new dairy comes on stream in August the estate will become a leading supplier of both quality milk and renewable energy," commented Gavin Davies, Stowell Farms’ manager.
"This project demonstrates how well biogas plants can compliment existing farming operations providing long-term benefits, with an index-linking income for 20 years," said John Day, sales manager for EnviTec Biogas UK.
