Climate Perspectives™ magazine | Anaerobic digestion at the heart of the system change needed to achieve Net Zero and energy security
Climate Perspectives™ magazine | By Charlotte Morton, Chief Executive, World Biogas Association > At the end of February, the Intergovernmental Panel on Climate Change (IPCC) issued part two its Sixth Assessment Report (AR6). Entitled Climate Change 2022: Impacts, Adaptation and Vulnerability, it describes the current detrimental impacts of climate change, deforestation, land use change, and pollution on people and the planet. Referring to the patchwork of pledges and ad hoc mitigations undertaken to date, the report says, “Half measures are no longer an option”. Systems change is now demanded.
An integrated bioeconomy
“Transformation and system transitions in energy; land, ocean, coastal and freshwater ecosystems; urban, rural and infrastructure; and industry and society, will make possible the adaptation required for high levels of human health and wellbeing, economic and social resilience, ecosystem health, and planetary health”, the report says.
The IPCC recognises an important role for the bioeconomy, stating that: “Bio-based products as part of a circular bioeconomy have the potential to support adaptation and mitigation. A sustainable bioeconomy relying on bioresources will need to be supported by technology innovation and international cooperation and governance of global trade to disincentivize environmental and social externalities (medium confidence).”
In an urban environment, this could see the integration of waste and energy streams through anaerobic digestion (AD) and the production of biogas and biomethane for heating, power, and transport. In the rural environment, agro-ecology and AD, as famously pursued in the biogas sector by traditional crop rotations systems and the famed Italian BiogasDoneRight model, provide a solution to decarbonise agriculture, restore soil health and provide economic sustainance to the farming sector.
AD for the bioeconomy and climate change mitigation
A core value of the AD process is that it transforms organic wastes (food, sewage, manure, slurries, agricultural wastes etc) into valuable bioresources such as biogas, a biofertiliser called digestate, bioCO2 and other valuable bioproducts. These can then be integrated into the bioeconomy and create a sustainable circular, low carbon economic system aligned with the demands of the IPCC.
Crucially, it also meets nine of the 17 UN Sustainable Development Goals and could contribute to achieving the Global Methane Pledge signed up by over 100 countries since its launch at COP26 last November. Reducing methane emissions has been recognised by the UN, the EU and agencies such as the IEA as the priority action required to achieve Net Zero targets by 2050 – and AD can make a massive contribution to the cause: if the infrastructure was put in place to ensure that all collectible and unavoidable organic wastes were recycled through AD, the industry could deliver 50% of the Global Methane Pledge target to cut methane emissions by 30% by 2030.
WBA research has shown that currently, only 2% of the 105bn tonnes of organic waste being generated by human activity annually is recycled through AD – that leaves a massive 98% untapped potential to produce biogas, biomethane, digestate and other bioproducts to feed into the bioeconomy and reduce methane and other greenhouse gas emissions. The mind boggles at the thought that such an opportunity remains to be seized.
Energy security – the new frontier
The production of green gas, fertilisers and other bioproducts through AD not only feeds into the bioeconomy and climate change mitigation goals advocated by the IPCC and other international bodies, but also helps strengthen energy security by displacing fossil-based equivalents imported from abroad.
Whilst the EU and the UK have already committed to a significant boost in biomethane production for environmental reasons, the tragic events in Ukraine have cast a fresh focus on the need for countries to free themselves from their dependency on oil and gas imports – not only as part of a package of sanctions on Russia, but also as an escape from the volatility of geopolitics and human rights and democratic abuses affecting international trade. There again, AD provides an ideal solution, helping produce energy – and food – from a locally-generated source: our daily waste.
Climate Perspectives™ magazine issue Q1 2023. Read the full issue here.
