In a surprising twist for the UK's energy strategy, cow dung is being championed as a vital resource to heat homes and bolster energy security. The GMB union is leading calls for the government to aggressively support a major expansion of biomethane production, arguing it could be essential for keeping millions of British households warm in the coming decades.
From Farm Waste to Home Heating
The process centres on anaerobic digesters, sealed units that mimic a stomach to break down organic material like agricultural and food waste. This process produces biomethane, a gas virtually identical to natural gas that can be fed directly into the national grid. While cattle farming is often criticised for methane emissions, this technology aims to harness the manure by-product positively.
Reports indicate the UK already has around 130 operational plants, producing enough biomethane to power approximately one million homes. With facilities under development, this figure is set to rise to 1.2 million. A compelling local example exists in Somerset, where the neighbouring villages of Nether Stowey and Over Stowey, with 1,400 residents combined, have been supplied with biomethane from a local farm for the past ten years.
A Vision for National Scale and Jobs
The GMB union believes this is just the beginning. It argues the technology has the potential to provide energy for between eight and ten million UK homes. The union is pressing ministers to back the sector to enable dramatic scaling-up.
Its ambitious proposal outlines increasing production to 50 terawatt hours (TWh) by 2030 and 120TWh by 2050. Achieving this, the GMB states, could meet up to 90% of the country's gas demand and create at least 60,000 new jobs. This potential exists despite a significant resource gap: UK agriculture produces about 82 million tonnes of livestock manure and slurry annually, yet less than 1% is currently used for biomethane production.
Beyond Heating: Transport and Global Potential
The application of biomethane extends beyond central heating. In 2023, Waitrose announced plans to become the first UK retailer to use renewable natural gas to power tractors on its Hampshire farm. Three years prior, the supermarket opened a biomethane filling station for its lorry fleet.
Globally, the International Energy Agency estimates that biogas from organic matter like cow manure could satisfy 20% of today's worldwide natural gas demand. Andy Prendergast, GMB National Secretary, made the case emphatically: "It may raise a wry smile, but cow dung really could be crucial to the UK’s clean energy future. It’s virtually identical to natural gas so can use existing infrastructure, it’s low carbon and – as any farmer will tell you – it’s only too renewable."
Scepticism and Diverging Views
Despite the optimism, not all analysts agree on the scale of biomethane's role in domestic heating. A study for the MCS Foundation charity suggested it could account for, at best, 18% of UK gas demand by 2050—a far cry from the GMB's 90% projection. In September, the charity's chief executive, Garry Felgate, stated: "Biomethane has an important role to play in decarbonisation - but not in homes."
The debate now rests on whether the UK government will heed the GMB's call and provide the policy support needed to turn this abundant, renewable resource into a cornerstone of the nation's energy mix.
