Program of Work 2019–2021

2. Rationale

The main objective of the Task 37 work programme is to address the challenges related to the economic and environmental sustainability of biogas production and utilisation. While there are many biogas plants in OECD countries, operation in the vast majority of cases can only be sustained with the help of subsidies to be able to compete with the fossil energy industrial sector. There is a clear need to enhance many of the process steps in the biogas production chain in order to reduce both investment and operating costs. This enhancement is now also required to effect significant decarbonisation and meet stringent sustainability criteria.

In 2013 – 2015 Task 37 produced reports on: substrates (sewage sludge, algae); pre-treatments including source separation of MSW; process optimisation (role of biogas in smart energy grids, process monitoring and nutrient recovery); and market development and trade of biomethane.

In 2016-2018 Task 37 reported on: substrates (food waste); optimisation of the sustainability of the produced biogas through measurement and minimisation of methane slippage at biogas facilities; system optimisation (greening of the gas grid; the role of biogas in circular economies; integrated sustainable solutions). Best practice in the lab was assessed through interrogation of the biomethane potential assay.

In 2019 – 2021 Task 37 proposes work on three broad themes: the role of biogas in energy systems; sustainability of biogas systems and methods to ensure good practice; and integration of biogas into processes.

To mitigate climate change, it is essential to develop integrated and sustainable decarbonised renewable energy systems. Heat and transport together, account for about 80% of final energy consumption. Significant progress has been made in renewable electricity but decarbonisation of transport fuel is problematic. Gaseous renewable energy carriers, such as renewable ‘green gas’ can have a considerable impact in future energy systems and play a key role in decarbonising heat and transport. Green gas at present is dominated by biomethane, which can be generated from the anaerobic digestion of organic biomass and residues produced in agriculture, food production and waste processing. In 2015, there were 459 biogas-upgrading plants in operation producing 1,230 M Nm3 of biomethane. The market for biomethane is still growing. Sweden, the UK, Switzerland, France and the Netherlands have all increased their biomethane pro­duction significantly in the last five years. In the short term, the development of green gas projects, including the injec­tion of biomethane to gas networks will be the primary focus of this developing industry. Management of this process will require a green gas certificate scheme to ensure sustainability and to allow trade.

Recent EU policy measures facilitate the develop­ment of such pathways with progressively increasing obli­gations on decarbonisation. The share in renewable and low-carbon transport fuels (excluding first generation bio­fuels and including for electrification) is required to increase from 1.5% in 2021 to 6.8% in 2030, with advanced biofuels to make up at least 3.6% by that time. Biomethane can provide this advanced biofuel for intercity buses and heavy commercial vehicles.

The on-going requirement to decarbonise will lead to integration of anaerobic digestion systems in other processes, be they agricultural, agri-food, waste management and or beverage industry. Anaerobic digestion would also be seen as an integrated element in the biorefineries of the future.

3. Challenges

There are many challenges to anaerobic digestion related to the economic and environmental sustainability of biogas production and utilisation. Task 37 must meet this challenge and provide expert evidence in areas where biogas systems offer innovative solutions and offer competitive advantage over other renewable technologies. This would include for example: the use of biomethane in heavy commercial vehicles; the flexibility of biogas systems and the potential to facilitate intermittent renewable electricity; the integration of biogas into other industries, including farming, beverage and biorefinery processes. Evidence and advice is needed to ensure best practice and compliance with stringent sustainability criteria, whilst ensuring minimum cost of energy. An overarching challenge is the communication of the evidence to highlight the benefits of the biogas industry.