Northern Ireland has successfully managed to decarbonise almost 50% of its total energy supply over the past ten years, research suggests.

However, this success has been achieved, for the most part, within the electricity sector, according to the latest figures.

This still leaves the transport and heating industries in Northern Ireland very dependent on fossil fuels.

According to Dr. Chris Johnston, a member of the agri-environment team at the Agri-Food and Biosciences Institute (AFBI), it is in this context that agriculture and land-focussed sectors can play a vitally important role into the future.

“Up to this point we have managed to decarbonise 2% of transport and up to 5% of heat," he said.

“These are where the hard to decarbonise problems exist and we need to focus on technologies such biomethane, biomass, hydrogen and sustainable cropping alternatives to deliver solutions.”

Johnston was one of a number of speakers at the 2022 AFBI science outlook conference.

Northern Ireland is already home to almost 80 anaerobic digestion (AD) plants. But, according to Johnston, a lot more can be achieved through the enhanced production of biomethane.

Recent assessments carried out by staff at AFBI and Queen’s University Belfast indicate that it would be possible to generate approximately 6000GWh of energy, in the form of biomethane from a combination of slurry and excess silage.

This sustainable energy source could then be fed into the existing natural gas grid.

Johnston highlighted at the outlook conference that the development of a sustainable bioenergy sector could also provide farmers with an opportunity to develop safe, nutrient management options.

He firmly believes that agriculture in Northern Ireland represents an extremely important source of bioenergy.

According to Johnston, AD can be placed at very centre of a circular bioeconomy. He has outlined the potential of extracting additional energy from the digestate leaving an AD operation.

He said this can be achieved in tandem with nutrient extraction, nitrogen and phosphorous, plus the development of markets for the organic fraction of the digestate prior to its spreading on land.

Johnston's envisaged biomethane production model centres on the development of AD hubs that would accept slurry and excess silage from farms within a 10-mile radius.

The AFBI expert also went on to confirm that there is a growing commitment to biomethane in many countries around Europe.

“Significant investment in this area is about to take place in the Republic of Ireland. However, Denmark now sources 40% of its natural gas requirements in the form of biomethane," he said.

“And the plan is to push this up to 100% in the near future.”