Towards carbon neutrality in on-farm biomethane production from break crops
Apsley Farms is an innovative agricultural business in Hampshire, UK, combining traditional farming with modern bioenergy technology. The facility is one of the largest biomethane producers in the country and has been feeding renewable gas into the UK gas grid since 2014. The plant is the third largest of its kind in the United Kingdom and houses one of the world’s largest plant-based fermenters with a capacity of 18 thousansd m³. The aim of the operation is to produce biomethane from agricultural sources.
This case study report is written by IEA Bioenergy Task 37 (Energy from Biogas).
The plant processes around 90 thousand tonnes of crops such as maize, rye, barley, oats and grass annually, most of which are grown on its own 465-hectare farm or by regional partners. Apsley Farms consistently uses sustainable farming methods, including minimal tillage, the use of catch crops, precise nutrient management and the efficient use of fermentation residues as natural fertiliser. The harvest is ensiled using the AgBag™ system, which reduces harvest losses, transport costs and emissions. With 385 Nm³ of methane per tonne of organic matter, the plant is one of the most efficient agricultural biomethane plants in Europe.
Some of the biogas produced is used on site in combined heat and power plants, but most of it is processed into biomethane and fed into the gas grid. The total output corresponds to 6.6 MW of electricity. The CO₂ separated during gas processing is liquefied, achieves food grade quality and is supplied to the British food and beverage industry. Over 60 thousand tonnes of biogenic CO₂ have been sold since 2016.
In addition to energy, Apsley Farms produces high-quality organic fertilisers and peat-free soil improvers from fermentation residues, which are also approved for use in organic farming. The company employs around 60 people and strengthens regional agriculture by providing reliable sales markets. The company also produces around 100 GWh of certified green electricity and gas certificates annually.
Overview of Apsley Farms biomethane plant.