Unchecked methane emissions persist as a significant concern, even for the production of biogas
In a startling revelation, a new study from Imperial College London has found that emissions along the biomethane and biogas supply chain in Europe are much greater than previously estimated. The research, which covered each part of the supply chain from production and upgrading, transmission, storage, and distribution, highlights the urgent need for improved practices and regulations to reduce these emissions.
The study, which analysed the most detailed measurement surveys conducted in various regions of Europe, mainly at agricultural plants, found that intermittent emission patterns, underusing process equipment, improper maintenance strategies, and less-than-effective design contributed to unnecessary emissions. About two thirds of the methane leaks were concentrated in a small number of super-emitter facilities and pieces of equipment within the chain.
Reducing CH4 emissions is crucial to stay "well below 2°C" as stated in the Paris Agreement, especially in terms of looming tipping points. Methane, which is over 80 times more potent than CO2 over 20 years, is also an air pollutant, causing serious health problems. The International Energy Agency argued last year that there is no room for any investments in new oil, coal, and gas production to respect the Paris Agreement.
The European Commission aims to produce 35 billion cubic metres (bcm) of biomethane per year by 2030 - double that of a previous objective set out in the Fit for 55 communication. Europe is the world leader in biomethane production by upgrading biogas, with Germany being the largest market and home to two-thirds of Europe’s biogas plant capacity.
However, the study showed that the overall biomethane supply chain emission profiles are similar to those of oil and fossil gas, with lower direct CH emissions than the fossil gas supply chain but much higher CH loss rates. Biomethane can be easily stored and injected into the existing gas infrastructure, similar to fossil gas, but the study did not directly address greenhouse gas emissions across the life-cycle. These emissions greatly depend on the feedstock used, with specific energy crops grown solely for energy production potentially worsening the life-cycle emission score.
The most effective ways to reduce emissions from biogas are continuous monitoring of biogas supply chains, proper detection, measurement, and repair techniques, and better regulations, continuous emission measurements, and close collaboration with biogas plant operators. Biogas derived from food or feed crops can undermine the potential mitigation benefits of biogas, and biogas developments should be based on waste or residues.
The International Energy Agency estimates that global biomethane and biogas production could satisfy nearly 20% of global gas demand in 2040 if its sustainable potential was fully utilized. In its RepowerEU Plan, the European Commission aims to replace parts of the Russian gas by alternative suppliers and biogas, especially for buildings and industry. More research is needed to determine where emissions occur and how to avoid them, especially for other geographic regions beyond Europe.
