Rising use of trees and crops for energy supply would lead to competition for land for food production and a loss of plant and animal diversity, according to a think-tank led by Lord Adair Turner, the former chair of the UK’s climate change committee.

The fierce debate about so-called bioresources comes ahead of the EU release next week of pivotal rules about what can be classified as “renewable energy”. Environmental groups are calling for the EU to strip forest biomass, essentially woody pellets, from the list.

At present, about 10 per cent of total energy is supplied by bioresources. This level could not rise without causing a significant knock-on effect to global food production or biodiversity, the report by the Turner-led Energy Transitions Commission concluded.

The ETC is a coalition of businesses, including BP, Shell, HSBC and the State Council of China, as well as other global institutions. It advocates for the development of alternative energy sources, such as clean electricity or hydrogen, produced by some of its members.

Turner said that while sustainably-grown trees and crops were in principle renewable, not all forms of their use was “good” from an environmental perspective.

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“[Bioresources] can only play a minor role in the total energy supply,” he said “We would be very wary of making it a big part of the decarbonisation story because we just think when you run the figures, the total sustainable amount [of bioresources] is likely to be small.”

The use of trees and oils from crops for energy has long been controversial, with scientists, campaigners, crop and forestry lobby groups arguing over the environmental impact. In February, more than 500 scientists wrote to the European Commission and European Council presidents, arguing against “shifting from burning fossil fuels to burning trees”.

The demand for biofuels has also led to volatility in the prices of food commodities in the past, triggering a backlash when food prices surged during periods of adverse weather and led to riots in poorer countries.

However, as the pressure on countries and companies to reduce their greenhouse gas emissions becomes heightened, the use of biomass as an alternative lower-carbon fuel has grown dramatically. In Europe, for example, biomass power generation has increased fivefold and the use of biofuels in transport 25-fold since 2000, said the report.

The International Energy Agency has forecast that 20 per cent of total energy demand could be met by bioenergy, in order to limit global warming caused by greenhouse gas emissions to a rise of 1.5C by 2050.

But the ETC argues for more rapid development of technologies including clean electricity or hydrogen, to reduce the need for trees and crops for energy generation. It says that current government policies often incentivise the use of bioresources in sectors where alternatives exist.

It said the use of bioresources should be prioritised for making building materials and as feedstock for plastic, as well as for plane fuel. But “bioresources should be a small part of the system”, Turner said.