As the world faces the dual challenge of mitigating climate change and improving the livelihoods of communities in developing regions, emission avoidance projects in the Voluntary Carbon Market (VCM) are becoming more important than ever. Among these, biogas technology, especially at the household and community level, is increasingly recognized for its potential to reduce greenhouse gas (GHG) emissions while delivering significant social and economic benefits.
Positioned as a key emission avoidance solution, biogas projects hold a unique position in the VCM. This article delves into how biogas projects work and their role in emission avoidance, the environmental and social benefits they provide, and the current way carbon finance can help overcome adoption barriers.
For a better understanding of what biogas is, read our article.
Biogas is primarily composed of methane (CH₄) and carbon dioxide (CO₂), produced through the anaerobic digestion of organic waste. Organic materials, such as animal manure, food waste, and agricultural residues are placed in air-tight digesters, where naturally occurring bacteria break down the material in the absence of oxygen. This process produces methane, which can be captured and used as a fuel for cooking, heating, or electricity generation, displacing the need for fossil fuels or non-renewable biomass like firewood or charcoal.
Methane has a global warming potential of approximately 25-28 times that of carbon dioxide over a 100-year period, making its avoidance, capture, and conversion use critical for effective climate action.
Methane Capture: Biogas digesters process organic waste (animal manure, crop residues, or food waste), converting methane into energy. This prevents methane emissions that would occur in unmanaged waste situations.
Displacement of Traditional Fuels: Biogas systems reduce the need for traditional cooking fuels like wood, charcoal, and kerosene. By replacing these fuels, biogas projects reduce CO₂ emissions associated with deforestation (for firewood) and the combustion of fossil fuels, thus contributing to emission avoidance on multiple fronts.
The social and economic benefits of biogas projects are well-documented, particularly in rural and low-income communities. For more information on why avoidance credits are not inherently inferior to removal ones, please read our article.
Beyond emission avoidance, biogas projects have a profound impact on the social and economic well-being of local communities, particularly in developing regions where access to clean energy is limited.
One of the primary social benefits of biogas systems is the improvement in household air quality. Traditional cooking methods, such as burning wood or charcoal, generate harmful smoke and indoor air pollution. This exposure is linked to respiratory diseases, which disproportionately affect women and children in rural households. Biogas burns cleanly, virtually eliminating indoor air pollution and reducing the risk of chronic respiratory illnesses.
The introduction of biogas systems also alleviates the time burden associated with firewood collection, a task that often falls on women and children. In many rural areas, women spend hours gathering firewood each week, which limits their ability to engage in education or income-generating activities. Biogas systems, by providing a clean and sustainable source of energy, free up time for women, empowering them to pursue other opportunities.
Biogas systems generate not only energy, but also valuable by-products. The digestate left over after biogas production is a nutrient-rich slurry that can be used as organic fertilizer. This provides a sustainable alternative to chemical fertilizers, improving soil health and boosting agricultural productivity. Households and small farms benefit from this additional resource, which can be used to enhance crop yields without the financial burden of purchasing synthetic fertilizers.
In terms of employment, biogas projects create local jobs in the construction, maintenance, and management of biodigesters. Communities that adopt biogas systems often develop networks of trained technicians who provide maintenance services, ensuring the long-term functionality of the technology.
Check out our articles for more information on the future of cookstove projects, and how cookstoves support SDGs.
Household biodigester bring many social and economic benefits. Yet, market uptake is often low. The widespread adoption of biogas digesters faces several critical barriers. One of the primary challenges is the high upfront capital investment required to build biogas digesters and the infrastructure necessary to deliver biogas to households. For many families, particularly in low-income communities, even small-scale systems are financially out of reach. The initial costs associated with setting up biodigesters, including materials, labor, and maintenance infrastructure, create a significant barrier to entry.
Moreover, biogas systems require a continuous supply of organic feedstock, such as animal manure, agricultural waste, or human waste, as well as water. This can pose logistical challenges in regions where feedstock is scarce or where water access is limited, especially in arid areas. Managing the fermentation process can also be labor-intensive, requiring regular feeding of the digester, monitoring of gas production, and maintenance to prevent blockages and ensure efficient operation.
Cultural factors also play a role in hindering adoption. In some regions, there is reluctance to use biogas systems due to concerns about handling animal or human waste for energy purposes. Additionally, biogas technology is less efficient in colder climates, where the anaerobic bacteria responsible for breaking down organic matter need warmer conditions to thrive.
Financial additionality refers to the fact that many biogas projects would not be economically viable without the income generated from carbon credits. In many cases, donor funding or government support is insufficient or temporary, leading to a decline in project implementation once external funding ends.
Carbon credit revenues very likely contribute to overcoming these barriers. One of the key contributions of carbon finance is its ability to remove upfront cost barriers by providing funding that helps scale biogas projects. Beyond supporting the initial installation of digesters, it also facilitates awareness campaigns to educate communities on the benefits of biogas compared to traditional cooking fuels.
Additionally, these funds can be used to train local entrepreneurs in the maintenance and repair of biogas systems, ensuring the long-term sustainability of the technology. Carbon credits provide an ongoing revenue stream that enables biogas projects to continue operating and expand, ensuring that both environmental and social benefits are sustained over time.
Although the emission reductions achieved by biogas projects are valuable, the quantification of these reductions can be complex. Methodologies used to calculate emission reductions often carry a risk of overestimation. For example, when biogas projects claim emission reductions by reducing the use of non-renewable biomass (e.g., firewood), they must estimate the fraction of biomass that is non-renewable. Biomass is non-renewable if the harvest rate in the region exceeds annual growth rates. All methodologies require that project developers determine how much of the firewood that households collect is non-renewable. This so-called fraction of non-renewable biomass (fNRB) is a key input value for calculating emission reductions, but difficult to estimate. Independent research has shown that default values used in many methodologies overestimate this fraction, leading to inflated emission reduction claims.
In the VCM, biogas projects generate carbon credits by reducing GHG emissions. Companies seeking to compensate for their emissions or contribute to climate change mitigation projects beyond their value chains can purchase these credits, which are validated by standards such as Gold Standard, or Verified Carbon Standard (VCS).
However, the quality of carbon credits from biogas projects depends heavily on the accuracy of emission reduction calculations and the project's long-term sustainability. Research has flagged potential risks related to non-permanence. Non-permanence refers to the risk that emission reductions could be reversed, for example, if households revert to using firewood or if the biodigester systems fail due to poor maintenance. Ensuring robust monitoring and providing ongoing support for communities are critical to mitigating these risks.
Despite the promising benefits of biogas projects, ensuring their long-term success and maintaining the integrity of their emission reductions requires careful oversight. At ClimateSeed, we address these challenges by employing a comprehensive due diligence approach that begins at the sourcing and qualification stage.
Our team of project experts meticulously reviews each project’s methodologies, monitors potential risks, and engages directly with project developers to ensure that all aspects—from emission reduction estimates to the long-term viability of the technology—are thoroughly vetted. This commitment to quality not only upholds the credibility of the carbon credits but also ensures that the social and environmental benefits are truly realized on the ground.
ClimateSeed is working with a Biogas Development Programme in China that supports almost 400,000 low-income rural households in Sichuan with advanced biogas digesters and smoke-free biogas stoves, which are installed and maintained by local technicians. The small-size biogas digesters tanks are fed with animal manure, previously just discharged into open pits, and converted into clean and affordable biogas to be used conveniently for cooking, heating, or lighting instead of coal and firewood. As a result, each participating smallholder farmer family saves about 2 tCO2e of methane and carbon dioxide emissions every year.
If you are interested in learning more about this project or exploring how biogas projects can support your climate strategy, feel free to contact our team at ClimateSeed. Our experts are ready to guide you through the process and help you invest in high-quality, impactful carbon projects.
For more information on the various types of carbon avoidance credits, please read our article.
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