Negative carbon footprint and biogas and biomethane production
Up-to-date material on the negative carbon footprint and how biogas and biomethane production reduces greenhouse gas emissions. Five important facts.
Biogas and biomethane are renewable energy sources that do not have emissions that fossil fuels usage is created. Livestock leads to the formation of large amounts of manure, which naturally produces a significant amount of methane during storage. If manure enters the closed and controlled environment of a biogas plant, this methane is captured and used to produce renewable energy. Thus, the production of biogas and biomethane from manure avoids the emission of methane from manure into the atmosphere.
Biogas and biomethane plants not only produce energy but also digestate. In this case, microorganisms convert organically bound nitrogen into a form more accessible for absorption by crops, making the digestate a valuable biological and green fertilizer. This green manure can reduce the use of mineral fertilizers, avoiding emissions associated with their energy-intensive production.
The inclusion of intermediate crops, such as cover crops, in crop rotation, has a positive effect on soil organic carbon. Organic resources increase through the root system.
Moreover, the use of digestate as a green fertilizer has an advantage in creating organic soil carbon, compared to the use of mineral fertilizers. Carbon from the digestate is captured in the soil and restores humus. Digestate thus allows soils to perform the function of carbon sequestration.
During the production of biomethane, a highly concentrated stream of CO2 is formed, which has many applications. The obtained CO2 can be used for the production of synthetic methane based on hydrogen (H2 + CO2 ➔ CH4), raw materials for the chemical industry (eg, methanol production), as well as for the production of fuel from electricity. It can also be used in industrial processes, such as the production of new building materials. It will help to achieve constant removal of carbon from the atmosphere.
The JRC study “Bioenergy Ways Based on Solid Biomass and Biogas: Inputs and Greenhouse Gas Emissions” estimates greenhouse gas savings compared to fossil fuels in the EU, up to 240% for biogas production and up to 202% for biomethane production, depending on the source materials and used technology.
According to a JRC study, to achieve a 240% reduction in greenhouse gas emissions:
- biogas should be produced from livestock waste,
- the biogas plant will have closed tanks for storage of digestate,
- electricity and heat required for the operation of the biogas plant must be produced by its own cogeneration plant on biogas.
Documents from the European Biogas Association (EBA) were used to prepare the material.