How do we reconcile the many demands that we place on the land – maintaining food security, producing energy, storing carbon and providing space for nature? One option is to reduce the amount of high-quality arable land taken out of food production to grow energy crops – 133,000 hectares of land (the size of Greater London) are dedicated to energy crops in the UK compared to less than 20,000 ha for solar.

An energy crop is a plant grown to produce biomass for generating heat, electricity and biofuels. Surprisingly, 90% of the energy crops grown in the UK are staple food crops – wheat, maize and sugar beet. This makes the growing of energy crops in the countryside all but invisible and rarely discussed.

Although planning permission is required for a change of land use from agriculture to other uses like a campsite or renewable energy installations, it is not required when replacing food production with non-food crops. In fact, government policy has encouraged farmers to diversify into non-food crops.

Energy crops are fed into the country’s 700 anaerobic digesters, which use bacteria to turn plant material into biogas (methane). The gas is burnt to produce heat and power used on the farm or by local factories and businesses. Anaerobic digesters were originally conceived as a way to use crop residues and wastes, even slurry, but the most common feedstock is maize, 75,000 ha of which is grown for energy.

Around 30,000 ha of wheat is grown in the UK to make bioethanol, which is added to petrol, up to 10% in E10 fuel, with the aim to reduce emissions from road transport following an EU policy dating from 2009. The UK only grows 25% of this bioethanol, importing the other 75% from the USA, Brazil and Ukraine. The sustainability of importing a product derived from a staple food crop to fuel the nation’s cars is rarely debated.

Crops diverted from food use to energy still require fertile land, water, fertilisers and pesticides, and energy to run farm machinery. Fertilisers are made from fossil fuel gas, and the nitrogen oxide that fertilisers release has 300 times more global warming potential than CO2. Energy crops have not met their promise to reduce emissions.

Worst of all, energy crops are staggeringly inefficient at producing energy compared to any other energy source. Solar can generate the same amount of power using only 5% of the land required to grow feedstock for an anaerobic digester. Plants only capture 1% of the sun’s energy, whereas solar PV captures 20% and does not need fertile soils or good rainfall.

The Government provides financial incentives under the Green Gas Support Scheme to build anaerobic digesters, paid for by a levy on our gas bills. The requirement to add bioethanol to petrol increases the price at the pump and ignores the reality that biofuels are high carbon.

We are kidding ourselves that biofuels reduce emissions, but they do increase food prices. Ending the growing of energy crops on fertile land would greatly boost our food security.