What if cow manure could heat a large slice of Britain?
But here’s the striking part: it already does for about a million homes, and experts say the potential is far bigger — up to 15 million households could be warmed by biogas derived from cow muck.
Biomethane, the renewable gas produced when manure is processed in anaerobic digesters, is already used in many central heating systems. A prominent campaign group, the Green Gas Taskforce, argues there is immense room to scale this up.
One Somerset dairy farmer, who treats his cattle waste as a valuable resource, calls cow manure “nature's crude oil.” His family farm has embraced the technology for years. In 2013 they invested £4 million to extract methane from cow waste, storing it in large tanks before feeding it into an anaerobic digester. There, bacteria break down the organic matter, releasing methane that’s captured and refined for use.
The gas is cleaned and regulated before it enters the national gas grid. Some of it powers Wyke Farms’ own cheesemaking operation, helping the business run on renewable energy. The farmer estimates that this process could heat around 10,000 homes per year from his herd’s manure alone.
The fundamental question remains: how much manure actually becomes usable gas? British cows produce roughly 90 million tonnes of slurry annually, yet only about 2.5% is fed into digesters. While the energy benefits — plus the possibility of selling surplus electricity — are clear, the upfront costs of installation deter many farmers.
In Nether Stowey, a village in the Quantock Hills, the local gas plant recently celebrated a decade of operation with a festive cake shaped like two domed gas tanks. The celebration underscores how deeply the community has become connected to biomethane; even the village’s primary school benefits from the gas produced nearby.
Not all digesters run on cattle waste, though. Some plants also process food waste collected by local authorities, which, after digestion, yields methane used in the same way.
Wales & West Utilities, which runs the national gas grid in the region, is keen to expand biogas production. They describe the southwest as a hotbed for anaerobic digestion and biogas, with about 20 biomethane plants currently operating in the area. The company envisions biomethane as a significant piece of the energy mix, potentially complementing hydrogen and electrification in a broader decarbonisation strategy for heating.
Campaigners from Green Gas Taskforce claim that if more digesters were built near farming operations and more food waste was diverted to these plants, up to 10–15 million homes could be heated with biomethane by 2050. They argue that such growth would bring investment and jobs to rural communities, not just urban centers, while helping decarbonise energy and improve local environments.
However, the expansion has its limits. There is a finite amount of cow manure to harvest, and critics worry about greenwashing: could biomethane displace fossil gas while still relying on other, non-renewable sources for the rest of the gas supply? Some think it’s possible to replace a portion of UK gas demand with biomethane, but not all of it.
Industry researchers, including Regen, suggest biomethane might replace as much as 18% of total UK gas consumption — a promising figure, but one that rests on optimistic assumptions. They stress that even 18% represents a best-case scenario, underscoring the need for additional heating and transport decarbonisation strategies.
Back on the farm, Richard Clothier remains convinced: harnessing cow manure is a straightforward, logical choice for dairy farmers. He notes the abundance of farm waste that could be channeled into digesters and transformed into methane, a resource that can both reduce reliance on imported energy and support the farm’s own energy needs.
In short, turning manure into gas offers tangible environmental and economic benefits, but achieving large-scale deployment will require careful planning, investment, and continued innovation in how we source and manage our energy.
