Hindle contrasted the government’s response to fracking – setting up a new agency, the Office of Unconventional Gas and Oil, to support the industry – with the lack of political interest in biogas, which is rarely mentioned by ministers.

One reason biogas has received less attention is that it falls between three government departments – energy, environment and communities and local government.

At present, according to estimates from the government’s Waste Resource and Action Programme, the UK throws away 15m tonnes of food waste a year, from homes, industry and retail. Only about 1m tonnes of the waste is used to generate biogas, or methane, using anaerobic digestion techniques that are well-established in other parts of the world.

This diverts resources to landfill and gives rise to greenhouse gas emissions, because the rotting food produces methane that is not captured and adds to the concentration of carbon in the air.

About 90m tonnes of animal waste is also produced in the UK each year, only a tiny portion of which is used for energy production. Sewage treatment plants are also overlooked. Biogas can be poured into the national gas grid and used for heating homes, burned to generate electricity, or used in specially adapted vehicles.

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