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SEPUR AN® GR EEN - 1,000 reference plant for efficient biogas upgrading
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Compressed Biogas Supply Outlook
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In conversation with Mr. Amit Anand
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Anaerobic Digestion and Biogas Technology: Design, Challenges, and Applications
How can we draw modern urban society to source-level waste management?
26 36 31 40 43
Unlocking Carbon Credits: The Role of Biogas in India’s Low-Carbon Future
Recommendation to boost the CBG industry-Reaction on Union Budget 2025 A Comparative Analysis of Kalundborg, Swedish Biogas, and Hamburg Biogas
Hydrogen sulfide in biogas: Generation and abatement guide
“Dear Readers and esteemed members,
Welcome to the latest edition of Biogas Magazine! As we progress through the first quarter of the year, we reflect on the recent union budget announcement, which brings much-needed relief to our nation's people across various sectors. Furthermore, we were thrilled to host the Webinar on Roadmap to Innovation and Sustainability, exploring new paths to a greener future.
The Indian Biogas Association also participated in the India Energy Week 2025 and contributed to the Petroleum Planning and Analysis Cell (PPAC) journal, further strengthening our commitment to industry advancement.
We are excited to announce the highly anticipated Bio-Energy Pavilion at the REI Expo, taking place from 30th Oct to 1st Nov 2025, at the India Expo Center, Greater Noida. This event promises to be a significant milestone in showcasing the innovations in bioenergy.
This edition features a curated collection of interesting articles exploring the current trends and advancements in the biogas business. We hope these pieces empower you with valuable knowledge to navigate the evolving landscape of biogas and bioenergy.
As we delve into the latest edition of Biogas Magazine, we bring you insightful perspectives on some of the most crucial topics shaping the biogas industry today.
We provide ideas to enhance the CBG (Compressed Biogas) industry in response to the Union Budget 2025, analyzing the potential policy changes that could accelerate its growth. We also explore the generation and abatement of hydrogen sulfide in biogas, offering a comprehensive guidance on addressing this issue effectively.
A comparative analysis of Kalundborg, Swedish Biogas, and Hamburg Biogas elucidates insights from global pioneers, while our article on unlocking carbon credits highlights how biogas can play a pivotal role in India’s transition to a low-carbon economy.
We also examine how contemporary urban society can be engaged in source-level waste management, offering solutions for more sustainable practices. Finally we discuss the design, challenges, and applications of anaerobic digestion and biogas technology, providing a comprehensive look at its future potential. We look forward to meeting you during RenewX (23-25 April, 2025) & BBB Summit (08-09 May, 2025).
Dr. A. R. Shukla President Indian Biogas Association
Chief Editor: Dr. Savita Boral
Editors: Abhijeet Mukherjee, Gaurav Kumar Kedia
Copy Editor: Mansha Tejpal, Dr. K. Rohit Srivastava, Lakshey Sehgal, Gautam Pandya
Creative Director: Jyoti Narang
Production: Jyoti Malik, Arjun Gambhir
Tech Support: Sangram Rout
Print Coordinator: Pawan Sahoo
Know us more
The “Indian Biogas Association” (IBA) is the first nationwide and professional biogas association for operators, manufacturers and planners of biogas plants, and representatives from public policy, science and research in India.
The association was established in 2011 and revamped in 2015 to promote a greener future through biogas. The motto of the association is “propagating biogas in a sustainable way”.
Steverding Agitator Technology
Steverding Agitator Technology is an expert in agitators. High technology is expected today at all levels of power generation. Steverding Agitator Technology can boast more than 20 years of experience in the manufacture of agitators. The continuous optimization and analysis of our products together with constant technical innovation show best results. Today, we are partners and system component suppliers of leading biomass facility manufactures in Germany, France, United Kingdom, Lithuania and many other countries.
This is our current range of agitators from Steverding Agitator Technology:
IBA's Commitment to Advancing Industry Prospects for Biogas/Bio-CNG
- Period: January '25 - March '25
Increase in credit limits to MSME- right step to boost CBG industry:
Indian Biogas Association (IBA) welcomes the proposed increase in MSME financing in the General Budget 2025 as the right step to boost the biogas industry. With a strong push for manufacturing, green energy, and digital transformation, this budget sets the stage for Aatmanirbhar and Viksit Bharat.
From the standpoint of the
fledgling biogas/CBG (compressed biogas) industry, the announced increase to the MSME Credit Guarantee Scheme will significantly benefit the biogas industry, which often faces challenges in securing credit with reasonable terms. By expanding the credit guarantee coverage from Rs 5-10 crore, the scheme ensures easier access to collateral-free loans, thus reducing financial barriers for the CBG developers. Additionally, the revised MSME classification criteria allow for almost 2-2.5 times higher investment and turnover limits as compared to the earlier regime.
Government’s Initiative on Soil Fertility shall foster industry growth:
The government has announced an amendment to encourage the use of organic fertilizer for farming methods that are more ecologically friendly. The Ministry of Agriculture and Farmers Welfare has made some revisions to the Control Order of 1985 Fertilizer (Inorganic, Organic, or Mixed) (Control) Order by officially including “Organic Carbon Enhancers” from Compressed Bio Gas (CBG) plants as a new variety of fertilizer. The change was introduced in February 2025 and is believed to be beneficial for both farmers and the environment in India.
As per the government’s announcement, Fermented Organic Manure(FOM) will qualify as “Organic Carbon Enhancer”.
It enriches soil with organic carbon, which aids in soil health, increases plant growth, and sustains agricultural productivity. Organic fertilizer, which is a by-product produced through the fermentation process in the biogas plant will allow the plant promoters to earn additional income. The notification boosts the existing framework by providing a new option to replace traditional fertilizers.
Indian Biogas Association (IBA) has been voicing for a long time for a SATAT-like scheme to be applied to Fermented Organic Manure (FOM). Now with this new legal acceptance of FOM as an organic carbon enhancer, further marketing and offtake opportunities can be explored which in turn shall favourably swing the viability of CBG projects. IBA estimates a minimum of USD 2.6 billion in revenue addition for the industry players
from Solid-FOM (as an organic carbon enhancer) upon full realization of SATAT potential. This figure would further increase by 2-3 times in case realization from the Liquid FOM (LFOM) is considered.
IBA-supported events on CBG:
IBA participated in the India Energy Week, which was organized from February 11-14, 2025, at Yashobhoomi, Delhi. For the participants, it turned out to be an excellent opportunity to explore diverse aspects of biogas and engage in insightful discussions. We also organized a knowledge-packed webinar on the Roadmap to Innovation and Sustainability on January 10, 2025. The webinar was part of our continuous endeavour to engage with biogas stakeolders through the "Renewing Renewable" series as it covered topics
related to project financing, biomass aggregation, sustainable farming, and the prospective investment landscape.
For the upcoming events, we are also pleased to announce that the RenewX is scheduled for April 23-25, 2025, at the Chennai Trade Centre, Chennai. RenewX will bring together industry leaders, innovators, and enthusiasts to explore opportunities, showcase advancements, and foster collaborations. Following the RenewX, we shall host the International Exhibition & Summit on the Bioenergy Value Chain, scheduled for May 8-9, 2025, at
Le Meridien, Delhi, India. This summit aligns with our mission to foster a Viksit Bharat and will focus on advancements in the bioenergy sector. For detailed information on our upcoming events, kindly visit our website.
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Compressed Biogas Supply Outlook
Policy initiatives to support CBG production
GOBARdhan scheme
The Galvanising Organic BioAgro Resources Dhan (GOBARdhan) initiative is a multi-ministerial programme aimed at converting biodegradable waste, including cattle dung, agricultural residues, and biomass, into valuable resources such as CBG and organic manure. It promotes a circular economy through a collaborative “whole of government” approach, integrating schemes like the Waste to Energy scheme by the Ministry of New and Renewable Energy and the Sustainable. Alternative Towards Affordable Transportation (SATAT) initiative by the Ministry of Petroleum and Natural Gas. Projects producing more than 10 cubic meters per day of CBG are eligible for funding under the GOBARdhan scheme. The 2023 Union Budget bolstered this initiative by announcing the establishment of 500 new “waste-to-wealth” plants with an INR 100 billion (USD 1.2 billion) investment.
SATAT initiatives
The SATAT initiative, launched in 2018, promotes CBG production from biomass waste to enhance energy security and
sustainability. SATAT focuses on extracting economic value from various biomass waste streams, including municipal solid waste, agricultural residue and sugar industry byproducts. The initiativen encourages the establishment of CBG production plants by independent entrepreneurs. These plants convert biomass into CBG, which is then distributed to fuel stations in cylinders.
To ensure the viability of these plants, oil and gas companies have committed to offtake CBG at a set minimum price for the first ten years of operation. This provides a stable market and revenue stream for the producers. This initiative aims to help reduce greenhouse gas emissions, lower fossil fuel dependency, and create jobs in rural areas.
CBG-CGD synchronisation scheme
Since 2021, the MoPNG has issued a series of policy guidelines for the synchronisation of CBG with CGD network requirements. GAIL has been mandated to implement this scheme, ensuring the supply of CBG mixed with domestic gas at a Uniform Base Price (UBP) to CGD entities for use in the CNG and residential PNG segments of CGD networks.
CBG, compressed to 200-250 bars, can be supplied via cascades for sale at retail outlets or injected into distribution pipelines at pressures specified by the respective CGD entities. To participate in the scheme, CBG producers must sign an agreement with GAIL to sell their CBG and enter a tripartite agreement with GAIL and the local CGD entity for the supply of CBG.
GAIL’s model has offtakes through both retail outlets and pipeline injection, but CBGCGD synchronisation has been achieved in only a few cities. Onground implementation remains limited, with companies primarily selling biogas through their own retail outlets to maximise value generation.
CBG obligations
In a significant step to promote the adoption of CBG in India, the National Biofuels Coordination Committee (NBCC) approved the phase-wise mandatory selling of CBG with CNG and PNG in the city gas distribution sector in November 2023.
Under this directive, obligations are set at 1%, 3% and 4% of total CNG and PNG consumption for the 2025-26, 2026-27 and 202728 fiscal years, respectively. From FY 2028-29 onwards, the
target will increase to 5%.
This policy is designed to stimulate demand for CBG while reducing India’s dependence on imported LNG. The government has underscored that noncompliance with the targets may result in penalties, potentially affecting the financial and operational performance of CGD companies.
Challenges for CBG adoption
Limited offtake
Currently, oil marketing companies procure CBG on a “best endeavour” basis, meaning they are expected to make reasonable efforts to purchase the product, but are not legally obligated for the same. This brings challenges for plant owners who face the risk of unsold inventory. The implementation of initiatives like SATAT and the CBGCGD synchronisation scheme remains limited, with companies primarily selling biogas through their own retail outlets to maximise value. Expanding CGD networks and linking them to CBG plants can address these issues by creating a reliable market for CBG, reducing transport losses, and minimising unsold inventory costs.
To facilitate this, the Government of India has introduced the Development of Pipeline Infrastructure scheme to create links between CBG plants and CGD networks, with a financial outlay of INR 9.9 billion (USD 0.12
billion) for FY 2024- 25 and FY 2025-26. This initiative aims to ensure the full offtake of CBG through cost-effective transportation and to maximise the utilisation of the CBG produced.
Stability of feedstock supply
Ensuring a stable supply of CBG in India faces several challenges, including seasonal biomass availability and inadequate logistics. Agricultural residues, abundant after the harvest period, become scarce at other times, necessitating efficient storage and reliable supply chains to maintain year-round CBG production. The widespread practice of burning agricultural residues, such as stubble, significantly contributes to air pollution in India, particularly in northern regions like Punjab and Haryana. Additionally, pressmud, a byproduct of the sugar industry, is often burned or dumped in landfills. Around 50% of municipal solid waste ends up in landfills, too, with 45-55% of it being organic matter suitable for biogas production.
These agricultural residues, along with pressmud and organic municipal solid waste, can be used as feedstock for CBG plants. However, inadequate transport and distribution infrastructure hinder the consistent availability of feedstock, necessitating investments in networks, storage and processing facilities. Furthermore, inefficient waste segregation contaminates biogas feedstock, damaging equipment and reducing production
quality.
While the government’s financial incentives and policy support are favourable for prospective CBG producers, long-term infrastructure development is essential for a stable CBG supply. To improve waste segregation, the government can offer tax incentives, run education campaigns, impose penalties and implement publicprivate partnerships with performance-based contracts.
Cost of land
The high cost of land can be a barrier to establishing biogas production units in rural areas. Access to affordable land can significantly enhance CBG production in India by reducing initial capital investment, particularly for small and medium-sized enterprises. Lower land costs can facilitate the establishment of CBG plants in rural areas rich in organic waste, such as agricultural residues and livestock manure. This not only reduces the cost of CBG production but also supports decentralised production, lowers logistical costs and promotes local energy generation.
State governments can drive the growth of the CBG sector by offering public land at affordable rates to biogas producers or providing other incentives for land acquisition, thereby attracting investment.
Policy hurdles at state level
A key obstacle to CBG development is the uneven implementation of policies at the state level. Despite significant potential, most states lack clear policies and incentives for CBG production. Currently, only Uttar Pradesh, Haryana, Bihar, andGujarat have bioenergy policies that actively support CBG, while states like Karnataka, Madhya Pradesh, and Maharashtra focus primarily on electricity generation from biogas rather than biomethane.
To address this, more state governments could consider establishing and enforcing comprehensive policies that prioritise CBG. This includes streamlining regulatory approvals, providing financial incentives, land assistance, and developing necessary infrastructure. Collaboration between central and state authorities is crucial to accelerating the growth of the CBG sector.
Marketing challenges for the CBG byproduct
Fermented organic manure (FOM) is a byproduct of the CBG production process, that can be sold as organic fertiliser, representing a vital supplementary revenue stream for CBG producers. However, these producers have faced significant hurdles in meeting the government’s quality standards for FOM, including requirements related to moisture content, carbon-to-nitrogen ratio and pH levels. Additionally, market demand for FOM from the farmers and fertiliser com-
panies has been undermined by the widespread availability of subsidised chemical fertilisers such as urea, and limited awareness by farmers.
To address these challenges, the Department of Agriculture and Farmers Welfare amended the fertiliser quality criteria in 2023. These amendments relaxed requirements for moisture content, carbon-to-nitrogen ratio and acceptable pH levels, making it easier for CBG producers to market their FOM byproduct as fertiliser. Furthermore, the Market Development Assistance (MDA) scheme, introduced in 2023, provides a financial incentive of INR 1500 (or USD 18.2) permetric ton to boost FOM sales and promote organic farming.
CBG supply outlook to 2030
As of September 2024, approxi-
mately 90 CBG plants were operational in India, with 77 of them falling under the SATAT and CBGCGD Synchronisation schemes. An additional 508 plants are in various stages of development, with about 150 currently under construction, indicating significant growth potential in the coming years. According to the GOBARdhan portal, Maharashtra, Madhya Pradesh, Bihar, and Tamil Nadu account for around 58% of the operational CBG plants.
In 2024, CBG production reached only 0.05 bcm. Key obstacles include the commercial viability of large-scale projects, as well as challenges related to land availability, access to desired feedstocks, offtake agreements, and the sale and distribution of FOM. By 2030, CBG production is projected to reach 0.8 bcm/ yr, at a capacity utilisation rate of 50%.
Excerpt from India Gas Market Report
To download full document, Please Visit: www.iea.org
In conversation with Mr. Amit Anand
1. The biogas and CBG sectors have significant potential for reducing greenhouse gas emissions. Could you elaborate on the key carbon credit mechanisms available for biogas and CBG projects in India? How can project developers effectively monetize their emission reductions?
Biogas is a relatively old technology, and there have been projects in India and globally that have benefitted from the carbon credit revenues that these projects have generated. Currently, there exist a variety of carbon credit mechanisms for GHG programs and standards worldwide, with the Verra and Gold Stan-
Amit Anand is the Chief Executive Officer (CEO) of Carbon Check (India) Pvt. Ltd. He has over 20 years of experience of working in Carbon Market in different capacities. During his professional career he has worked as consultant and was involved in development of GHG avoidance projects and for the last 14 years he has been involved in validation & verification of GHG avoidance and removal projects in CDM/ VERRA/ Gold Standard for the Global Goals (GS4GG) and plastic waste reduction projects under VERRA.
Mr. Amit Anand Chief Executive Officer
Carbon Check (India) Private Limited
dard being the most significant. In the future, these mechanisms will be incorporated into Article 6.4 of the Paris Agreement, known as the Paris Agreement Crediting Mechanism. Including other standards as well, e.g, an international carbon registry based out of Iceland, social carbon, and Cercarbono from Colombia. Hence there are multiple GHG programs in the Voluntary space. In the compliance space, we have CDM which currently is transitioning into Article 6.4 of the Paris Agreement. So primarily if you look at it, from India’s perspective, the 3 mechanisms that come to my mind are Gold Standard, VCS of Verra, and the Paris Agreement Cred-
iting Mechanism which will become operational soon. Hence, these are the 3 mechanisms that the farmers or the stakeholders in the biogas/CBG domain can explore to avail the benefit of the Carbon credit mechanism.
2. Various stakeholders, such as plant developers, technology providers, and farmers, contribute to the success of biogas and CBG projects. How do these stakeholders individually or collectively benefit from carbon credits, and what role does collaboration play in maximizing their gains?
Any successful project has to be a collaborative effort. Various
stakeholders are involved in this kind of project, like farmers who are responsible for providing the raw materials either in the form of cattle waste, cow dung, or agricultural waste. Even village households can provide their kitchen waste. Also, the tech providers, project developers, and regulatory authorities play an important role. To effectively monetize carbon credits, one has to also understand that it is a complex process that requires the selection of the right standards, i.e, which standard do we want to use, e.g. do we want to use the compliance standard like the Paris Agreement Crediting Mechanism or the voluntary standards like the Gold standard or Verra.
Also, an understanding of the current market dynamics, and how lucrative the biomass sector would be at any given point in time, corresponding to the revenue, you can generate from the sale of carbon credit. Additionally, the knowledge regarding the requirements of the standards, i.e. how to develop projects under those standards choosing the appropriate technology and a reliable technology partner is crucial for the successful execution of these projects. Whether that technology provider will also provide the necessary support in terms of upkeep of the equipment, maintenance, and steady supply of raw materials from the farmers would be the key, because if we do not have sufficient raw materials or the steady supply of raw materials,
then operations of these projects become very challenging. Hence, at every level, there has to be a collaborative effort so, identifying the right partners and what roles they can play in this entire cycle is equally crucial. Once the project is established and operational, comes the key part of preparing the required documents and submitting those documents to register under the Gold Standard program. We haven't yet completed the work. After registration, continuous monitoring is required. If it is a commercial/large-scale plant, you can opt for online monitoring, or sensor-based monitoring; you can have digital tools to monitor the operational parameters of the plant, but even if it’s a decentralized structure, like the household biogas plant, which we see is increasing because farmers are aware that digesters of 1 cum or 2 cum can also meet their household energy requirements in terms of their cooking needs. So, if we are looking at a decentralized structure of a project, that caters to the decentralized biogas systems, then you would also require the constant support of individual farmers and households in terms of operational parameters, helping out with the monitoring of the plant.
It has to be, therefore, a collaborative effort from the very beginning, starting from the identification of the location where you wish to set up the plant, identification of the feedstock provider ensuring the continuous supply
of the feedstock, identifying the right tech provider who will provide us with the equipment, machinery, and identification of the right partners who can take you through the entire carbon credit cycle. Apart from this, you need to have the support of the farmers for monitoring and ensuring the continuous operation of the plant/small biogas digesters to ensure that the carbon credits are generated and delivered. So, there has to be a lot of collaboration, the roles and responsibilities needs to be aligned, fixed and explained. A lot of awareness has to be imparted to all the stakeholders who are involved.
3. One of the major hurdles for biogas and CBG project developers is navigating the complex certification and verification processes for carbon credits. What are the common challenges in getting projects certified under global standards like VCS (Verified Carbon Standard) or Gold Standard? How can developers streamline this process to ensure faster credit issuance?
Carbon credit project development is slightly complex, as this is not a naturally acquired knowledge through your education or work experience, so there are selected organizations that deal with these kinds of projects. One of the challenges is to identify the right partner who understands your expectations, and it is also important to understand the track record
Interview
of those partners in this kind of sector and technology. When you start developing a carbon credit project, there are a few basic steps, the first one being the identification of the type of project. The second parameter is the identification of the right standard because every standard has a different set of requirements. At this stage these community-based projects, (individual, small household level biodigesters also contribute to the Sustainable Development goals, whether you want to choose a standard that has an inbuilt mechanism to quantify the project’s contribution to Sustainable Development goals or you want to go for a standard in which you can at a very later stage opt for the quantification/ certification of the Sustainable Development goals, because these will also have an impact/ implication on the overall cost and timeline of the process.
Therefore, finding the right standard that aligns with your objective is crucial. Furthermore,, understanding the requirements of the standard, and how the project has to be developed is important because sometimes the project is there but when it comes to the documentation part, the documentation isn’t up to the mark and that poses a lot of challenges in validation, verification, registration, certification, and issuance, because, the standards have a certain requirement, clearcut guidelines, and procedures that one has to follow. Thus, identifying the right
partner for getting these projects registered under the Carbon credit mechanism, is very important as we need to identify a partner who is very well versed with all these requirements, understands and interprets these requirements, and is very well aware of the changes that are going to happen in these standards, and how they will impact the project at a later stage.
One of the key challenges is also how you design your monitoring. There are key elements of a project. Identification of a proper baseline (what was happening in the absence of the project activity) or what is the right business-as-usual scenario. The identification of the right baseline scenario will result in the generation of carbon credits. Hence, proper identification, calculation of the emission reduction, and use of the right formulas, tools, and approaches are required.
Therefore, the challenges are about the project documentation, selection of the right partner, and selection of the right technology from the right kind of stakeholder. You also need to understand the limitations of your partners with whom you are working and design a project, which can work beautifully within their limitations while delivering you the best results. Ultimately, you are going through a carbon credit process and if the documentation is not up to the mark, then it leads to a lot of delays. In some cases, not un-
derstanding the requirements can cause such initiatives to fail. So, one must be quite thorough about these requirements.
4. With India aiming for net-zero emissions and the government actively promoting clean energy, how do you foresee the future of carbon credit trading for the biogas sector? Are there any upcoming policy changes or global market trends that project developers should be aware of?
India has a target to achieve net zero by 2070, which is not an over ambitious target. But clean energy will have a vital role to play. If you look at the socio-economic situation of India, farmers are at the bottom of the economic pyramid where their sustenance is at stake. These kinds of projects also provide additional revenue to the farmers and augment their livelihood source of income. Going forward, India is at a very advanced stage of developing its domestic carbon market and the key sectors have already been identified, which would be required to reduce their emission. Since they would have a target, they would have to either reduce their emission intensity in their backyard or invest in biogas/CBG projects/buy or sell carbon credits.
The Biogas sector as a whole will not have any target to reduce emissions as it is a clean energy sector. This sector could become one of the suppliers of such credits shortly. The biogas/CBG
sector can accelerate India’s journey to achieve the netzero target and also help other Indian industries and energy sectors to meet their emission reduction targets or reduce their carbon footprint, which will ultimately contribute towards India’s net-zero commitment as well. Hence, I think this sector has a huge role to play, and thus this would be an exciting time for the biogas/CBG sector because traditional Renewable energy sectors like wind, solar, etc, are being developed under the Renewable Purchase Obligation (RPO) so they may or may not be able to supply that kind of credits that would be required to aid India’s journey towards achieving net zero in the future. The newer clean energy sectors would be much more in demand. From personal experience, I can say that the biogas/CBG sectors are well placed to be at the forefront of this remarkable journey of India towards net zero.
5. The price volatility of carbon credits often affects project financials. How should biogas/ CBG project developers strategize to ensure stable returns from carbon credit trading? Do you see long-term purchase agreements (LPAs) or partnerships with corporate buyers as a viable solution?
Carbon credit is a market-based mechanism, so market volatility will be there. It is like every other market hence, there will be ups and downs/fluctuations. First and foremost, the thing
that I have constantly observed over my 20-year-long career about the carbon market is that sometimes the expectations of the project developers are not realistic. Unrealistic expectations also hamper the sector because it is pertinent to understand it and the market. When carbon credit project developers reach out to stakeholders for such kinds of projects, there is a problem with commitment. There is a problem of overcommitting the prices, as prices are not within somebody’s control, it is completely market-driven/ controlled. E.g. if you commit to the farmers that there will be 10 USD per credit, and you are unable to live up to that expectation, then in a certain sense that is deemed as a failure. However, if you start a project with a very realistic expectation, and do your groundwork thoroughly, that helps.
A carbon credit mechanism isn’t there to make any project profitable but to mitigate some of the barriers that may lead to the non-implementation of this kind of activity, or which may not allow the sector to grow or realize its full potential. So, the carbon credit mechanism is only meant to alleviate those barriers, you can scale up your activity and there are a lot of replications of this kind of activity. That is where it's misunderstood and some of the project developers think that the carbon credit market is there to augment their revenue stream. The carbon credit market isn’t to make you
rich/profitable; it is to aid you in adopting these kinds of new technologies which were not being adopted in certain conditions because there are some challenges in working with this technology. So, when you start with your project, I would expect everybody to be very realistic, do thorough due diligence, design their projects, look at the financials, and then decide the prices of the credits.
If the market price is 4 USD and you could secure a Long-term agreement (LTA) for 6 USD in that case it is a very good business prospect. But after 4-5 years the market has gone up and now you see the prices have jumped to 10-12 USD, then the same LTA doesn’t seem to be working in the favour of the project developer. However, if you do your work realistically and you think that even if I get 4-4.5 USD per credit, it breaks even for me and then I can have a certain 1.5 dollars extra which I can utilize for providing to other partners, and stakeholders and I can use in scaling up this project, then in that sense it is still a good deal.
Therefore, one has to be realistic about what we expect from a project. But yes, the long-term purchase agreement (LTPA) does help as they to a certain extent rule out the volatility of the market. Also if you can find an investor or the right partner who can invest in a project or a technology, there are various models on which these proj-
Interview
ects could be developed. One is the LTPA for the emission reduction credits, there are also models in which there is some pre-payment of the entire project cycle cost because carbon credit issuance is not certain, it is subjective. The project may get issuance, or it may get rejected. That’s an inherent risk in this entire cycle. You need to find the right investor who understands the entire cycle and who is willing to take those risks to a certain extent or is willing to bear the carbon credit project cycle cost and thus helps alleviate the risk. There are different models to it and LTPA seems to be a reasonable solution. However, as discussed earlier, one of the most critical factors is having a realistic expectation of carbon credit pricing.
6. Many new players, especially smaller biogas entrepreneurs and farmer cooperatives, are interested in tapping into carbon credits but lack expertise in the process. What advice would you give them to successfully enter and benefit from the carbon credit market?
First and foremost, is the identification of a problem, which could be the dumping of cattle waste, unmanaged disposal of kitchen waste/organic waste, or burning of organic crop residues. Hence, it is important to consider the problem statement you are looking at. Thereafter, we come up with a solution –biogas. Next, we need to look at the feasibility of the project from
the technical point of view. First, you earmark an area where you want to develop a project. Then you look at the feedstock available in that region as that is one of the most critical components. This is required to ensure that you plan your project in a location with a surplus availability of feedstock (at least 25% more availability than your requirement). Based on that you start designing your project. Simultaneously you need to look at the costs associated with all the processes. Then identify the right partner for the carbon credit project development. A typical carbon credit project is not feasible at every scale, hence you have to look at the scale carefully. A very small-scale project will not make much business sense for the project developer as the project cycle cost will be higher than the profits accrued. E.g. coming up with a project with about 10 biogas digesters, each with a capacity of 1 cum or 2 cum, will not make financial sense because the cost that you will incur in going through the project cycle will be higher than the revenue generated.
It is important to understand the scale at which the entire effort could be fruitful. So, finding the right scale/size of the project and then finding the right partners, and developing the project documents as per the requirements of the standard are of equal importance. One of the key elements is the constant communication between the consultant and the project
owner/developer. In a typical carbon credit project, the project developer is the most important stakeholder as he is the one who will be implementing/ running the project and whose efforts will result in carbon credits. That entire process has to be compatible with the preparation of the documents so that at a later stage there are no surprises. Hence, for these young entrepreneurs, small project developers, and farmers/farmer cooperatives, the idea is to find the right partners and be realistic about the expectations.
Sometimes the stakeholders go into the loop of designing a perfect project. There will always be some ups and downs in the entire cycle so it will never go as you planned. It is important to understand that we can’t decide to do a perfect project and then go in carbon credits as the carbon credit standards have some timeline restrictions. It is always better that you start the thought of carbon credit at a very initial stage (project design/ discussion stage). It is important to consider carbon credit revenues in your entire decision-making process as it also helps you demonstrate the additionality which simply means why the carbon project would not be implemented without carbon credit revenues. One of the key things I would like to advise is to think of everything from the beginning, along with the carbon revenue for developing such projects.
Biogas production occurs through anaerobic digestion, a process where microorganisms break down organic matter in the absence of oxygen within a closed system known as an anaerobic digester or bioreactor. This process involves a series of metabolic reactions: hydrolysis, acidogenesis, acetogenesis, and methanogenesis. Initially, complex organic polymers are broken down into simpler molecules such as sugars and fatty acids. Acidogenic bacteria then convert these into volatile fatty acids, carbon dioxide, and other by-products. Finally, methanogens utilize these intermediates to produce methane and carbon dioxide. The balance between acid-forming and methane-forming microorganisms is crucial for maintaining reactor stability, as imbalances can lead to process failures. Environmental conditions such as temperature, pH, and the presence of inhibitory substances also significantly affect the efficiency of anaerobic digestion and biogas production.
2. Composition and Variability of Feedstocks
Biogas feedstocks are diverse and originate from various sectors, including agricultural, industrial, and municipal
operations. These feedstocks encompass a wide range of organic materials such as animal manures, vegetable by-products, energy crops, organic industrial wastes, municipal solid waste, and sewage sludge.
Agricultural Feedstocks: Include animal manure (e.g., cattle, pig, and chicken) and agricultural residues like vegetable by-products and energy crops. The composition of these feedstocks varies significantly, affecting their biogas production potential.
Industrial Feedstocks: Comprise organic wastes and residues from agro-industries, food industries, and biofuel production. These feedstocks often contain high levels of organic matter but may also include inhibitory substances that can impact anaerobic digestion (AD) efficiency.
Municipal Feedstocks: Encompass source-separated household waste, sewage sludge, and municipal solid waste. These materials are rich in organic matter but can be heterogeneous in composition.
3. Factors Influencing Biogas Yield
Total Solids (TS) and Volatile Solids (VS): The TS and VS content of feedstocks are critical in determining biogas yield. Higher
VS content typically results in higher methane production.
Chemical Composition: The presence of carbohydrates, proteins, fats, cellulose, and hemicelluloses influences biogas production. Fats and proteins generally produce more methane than carbohydrates, while lignin is not biodegradable under AD conditions.
Carbon-to-Nitrogen (C/N) Ratio: An optimal C/N ratio of 2035:1 is essential for efficient biogas production. Deviations from this range can lead to reduced methane yields or process instability.
Biogas Yield Categories
Biogas yields can be categorized based on the volume of biogas produced per ton of VS:
Low Yield: Less than 300 m³/t VS, typically associated with lignocellulosic materials and certain animal manures.
Modest Yield: Between 300-500 m³/t VS, common in chicken manure, municipal solid waste, and some agricultural residues.
High Yield: Exceeding 500 m³/t VS, often observed in abattoir effluents and potato starch effluents.
Understanding these factors is
crucial for optimizing biogas production and selecting suitable feedstocks for anaerobic digestion processes.
Feedstocks
4. Barriers to Feedstocks in Biogas Production
Biogas production from agricultural substrates faces several challenges that limit its contribution to the energy system. Key barriers include:
Economic Viability: High construction costs often hinder the profitability of biogas facilities. However, when farmers pool their experiences and manage operations themselves, economic viability can be achieved. Feedstock Characteristics: Animal slurries, such as pig and cattle slurries, have low dry matter content (3–5% and 6–9%, respectively), resulting in low methane yields per unit volume of digested feedstock. This, combined with high biomass transport costs, further complicates
economic feasibility.
Contamination in Municipal and Organic Wastes: Municipal and organic wastes often contain undesirable substances like pathogens, fungi, and chemical pollutants. Household waste, in particular, requires costly separation and sanitization to remove contaminants before anaerobic digestion (AD).
Industrial Waste Limitations:
While industrial wastes offer high methane yields, they may contain physical impurities, heavy metals, or persistent organic compounds. These contaminants pose environmental and health risks if the digestate is used as fertilizer, necessitating strict control over foreign material content.
Shortage of Organic Waste: In regions with well-developed biogas markets, there is often a shortage of organic waste, particularly high-yielding "methane boosters." This scarcity can limit the expansion of biogas production.
Logistical Challenges: The collection and separation of organic matter from other residues are costly processes. Additionally, the transportation of biomass over long distances is economically constrained due to its low energy density and diluted nature.
Addressing these barriers is crucial for enhancing the efficiency and sustainability of biogas pro-
duction from various feedstocks.
5. Biogas Utilization as a Substitute for Natural Gas
Biogas, primarily composed of methane (CH4) and carbon dioxide (CO2), has gained prominence as a natural gas substitute due to its potential to reduce greenhouse gas (GHG) emissions and mitigate the depletion of natural gas resources. However, its lower calorific value compared to pure methane necessitates upgrading to biomethane, which involves removing CO2 and other impurities like hydrogen sulfide (H2S) to achieve a methane concentration of over 97%.
6. Upgrading Technologies
Several technologies are employed for biogas upgrading, including pressure swing adsorption (PSA), high-pressure water scrubbing (HPWS), organic physical scrubbing (OPS), chemical scrubbing process (CSP), membrane separation, and cryogenic separation. Membrane separation is noted for its economic and environmental advantages over traditional methods, with future developments potentially reducing production costs.
7.Economic and Environmental Considerations
The capital and operating costs of biogas upgrading depend on factors such as the selected process, raw biogas quality, desired product quality, and plant capacity. Biomethane production is more viable in economies with strong environmental goals and sufficient biogas capacity. It can be compressed into compressed natural gas (CNG) for use in vehicles, though its economic feasibility varies by location and infrastructure availability.
Environmental Benefits
Biogas and biomethane offer significant environmental benefits by reducing GHG emissions through the displacement of fossil fuels and the utilization of organic waste, which would otherwise decompose and release methane into the atmosphere. Additionally, the digestate from biogas production can be used as a biofertilizer, reducing the demand for synthetic fertilizers and contributing to a circular economy.
...to be continued in next edition of Biogas Magazine
Meet the Author
Mr. Mainak Ray Deputy Manager - R&D and Innovation HPCL- Mittal energy LTD
How can we Draw Modern Urban Society
to source-level waste management?
Introduction The Urban Waste Issue
The solid waste Challenge that modern cities all around face is growing. Over 2 billion tonnes annually, global municipal solid waste (MSW) generation is expected to reach 3.4–3.8 billion tonnes by 2025 (Global Waste Management Outlook, UNEP, 2024). Changing lifestyles, rapid urbanization, and economic expansion all contribute to create this surge. Sadly, at least 33% of the world's trash is not handled in an environmentally
Waste Management
friendly way (What a Waste 2.0, World Bank, 2018). Low-income nations dump or burn over 90% of their waste without any treatment (What a Waste 2.0, World Bank, 2018). Severe implications from these developments include overflowing landfills, pollution, greenhouse gas emissions, and public health risks. We desperately need creative ideas for more environmentally friendly garbage management at the source, using segregation and on-site processing. How then can we inspire and include contemporary urban culture in this vital habit? The limits of centralized waste systems are investigated in this article together with ways in which technology, policies, and community involvement might draw urban people to engage in source-level waste management.
Why would CBG plants not be able to address India's entire waste problem?
While centralized biogas facilities are efficient for processing large-scale agricultural or industrial waste, they face significant challenges in managing unsegregated municipal solid waste (MSW). One major cause is contamination; about half of mixed urban garbage consists of plastics, glass, and metals, therefore upsetting digestion and raising operational costs. For example, despite spending about ₹100 crore (Hindustan Times, 2022 June 28), Pune's municipal corporation had to close 25 scattered biogas facilities due to on-
going operational problems and expensive maintenance costs. In Bengaluru, 10 out of 13 community biogas plants also failed within a few years, mostly due to mixed garbage being too heterogeneous and contaminated for conventional biogas technology to manage effectively (Times of India, 2019 May 2). These encounters underscore the need for complementary, distributed, source-level waste management solutions, which can effectively handle mixed organic wastes, lower transportation costs, and provide stable, reliable biogas generation right where waste is created.
Various polls indicate that India's metropolitan areas are experiencing a growing garbage dilemma; cities produce around 62 million tons of municipal
solid waste (MSW) yearly, and by 2030 this number is predicted to almost triple. With barely 40% of urban organic waste fully separated in India, largescale facilities find it challenging and expensive to run effectively because of contamination, transportation costs, and logistical complexity. Decentralized, source-level waste management systems are a dependable substitute as they let businesses, hospitals, hotels, and canteens handle waste at its place of generation itself, therefore greatly lowering these problems. These technologies completely replace expensive transportation, therefore lowering greenhouse gas emissions, improving waste separation, and directly involving waste generators in environmental responsibility. Processing waste on-site significantly reduces landfill reliance, lowers methane emissions—methane being 25 times more harmful than carbon dioxide (Quantifying Methane Emissions from
Landfilled Food Waste, EPA, 2023)—and immediately generates financial savings by offsetting LPG or electricity costs. By means of the Solid Waste Management Rules 2016, India already requires source-level treatment of organic waste for bulk garbage producers. Therefore, an efficient sustainable address to India's expanding waste challenge depends on improved source-level waste management systems.
Why Modern Society Refutes to Adopt Source-Level Organic Waste Management?
Although source-based management of organic waste has obvious advantages, urban communities are reluctant to install traditional biogas plants, mostly owing to practical issues and lifestyle conflicts. Traditional biogas systems aren't used in places like hospitals, institutional canteens, hotels, and apartment complexes because they don't meet the necessary standards for cleanliness, appearance, and functionality. Many organizations worry that implementing traditional biogas plants could bring problems, including odours, pests, or regular maintenance requirements—issues that are incompatible with modern urban living and the constrained spaces available in cities. Moreover, mixed organic waste—especially food waste with different rates of digestion—is inadequately processed by conventional biogas technologies, which causes operational instability and regu-
lar system failures. Recent studies indicate that these problems cause operational difficulties or ultimate closure for around 77% of small-scale biogas plants erected all around metropolitan India. The lack of smart moni toring systems and automation makes things even worse. This means that more maintenance and intervention work needs to be done by hand, which makes these activities less appealing to people in cities. Therefore, innovations must give user-friendliness, effective mixed trash handling, and automated operations with IoT monitoring top priority for India's urban society to embrace source-level waste management solutions; also, compact, aesthetically pleasing designs fit for current urban environments.
Specifications for a Source-Level Waste Management System Compatible with Modern Lifestyle
Urban India can really adopt source-level waste management if the methods fit modern lifestyles and satisfy particular practical and aesthetic requirements. First, modern systems have to efficiently manage mixed organic waste—that is, food waste including elements high in carbohydrates, proteins, and cellulose-rich components, each needing differing digestion times. Standard biogas facilities generally fail here because of homogeneous digestion designs, which cause low efficiency and regular operational prob-
lems. Second, urban systems have to be aesthetically pleasing and compact. In highly crowded locations, space constraints call for systems that occupy little area yet provide hygienic operations free of odours. Thirdly, IoT integration and automation are vital; automatic monitoring and self-corrective features guarantee consistent operations, hence drastically lowering manual interventions. Systems that offer real-time status updates and alarms help users to easily keep ideal efficiency. Finally, a user-friendly design addressing issues of cleanliness, safety, and smells is non-negotiable for acceptance in urban environments.
WENERATOR® produced by Vivifica Sustainable Solutions is one instance illustrating these values. This 350 kg/day biogas system was just installed at SP Medifort Hospital in Thiruvananthapuram. Its sleek design, ability to handle mixed organic waste well, and strong IoT-enabled automation make it a great fit for cities. WENERATOR conveniently fits modern lifestyles and covers all basic urban needs, therefore greatly lowering operating costs and landfill dependency.
Promoting Urban Involvement in Organic Waste Management at Source Level
Driven mostly by fast urbanization and changing consumption patterns, India's urban waste management presents major issues that result in the daily gen-
eration of large volumes of organic garbage by cities. Although nearly half of India's municipal waste—about 85,000 tons daily—is organic, effective management is still elusive because of poor segregation and pragmatic difficulties at the source. Although centralized alternatives like Compressed Biogas (CBG) facilities have attracted government subsidy under programs like National Bioenergy Program, their shortcomings—particularly in terms of handling unsegregated waste and logistical problems—highlight the pressing necessity of complementary decentralized approaches.
Still, metropolitan areas sometimes hesitate to implement source-level organic waste solutions even with their clear financial and environmental benefits. This resistance mostly results from impressions of hygiene, unpleasant smells, aesthetics, operational complexity, and space limits usually connected with traditional biogas facilities. Today's urbanites want waste management systems to fit perfectly into their contemporary way of life without sacrificing their daily schedules or aesthetic appeal. Because of their demanding operation, regular maintenance needs, and ugly look, traditional systems can fall short of these objectives.
Modern waste management systems have to fully address these pragmatic and psychological obstacles if they are to draw urban populations toward source-level
control. By encouraging policies that incentivise distributed waste management through subsidies, tax incentives, or reduction in municipal costs for bulk trash generators deploying on-site solutions, governments and municipal authorities can play a major part. Teaching local communities about real environmental effects, like less reliance on landfills and decreased greenhouse gas emissions, would help them to feel collectively responsible and proud of actively engaging in sustainable living.
Furthermore, urban areas seek clear financial incentives. While producing valuable biogas for cooking or heating, so lowering
LPG and energy consumption, decentralised biogas systems can greatly cut or even eliminate waste disposal expenses averaging roughly ₹5 per kilogram for urban food waste in certain of Indian cities. Showing effective pilot projects such as the contemporary source-level biogas system at SP Medifort Hospital in Thiruvananthapuram, shows these direct savings and gives hope to possible urban users. Operational dependability also drives acceptance. The integration of IoT-enabled automation, accurate monitoring systems, and automated preventive actions guarantees user-friendly experiences, greatly minimizing operational interruptions. Government help in this area would
Waste Management hasten adoption rates utilizing focused awareness campaigns, subsidies for first installations, simplified rules for distributed waste management, and appreciation of institutions implementing innovative waste management techniques.
In the end, one needs balanced, dual-strategies including centralized and distributed systems. While massive CBG plants address high-volume waste streams, modern, visually beautiful, and dependable source-level solutions have to become natural components of urban India's waste management system. Modern biogas plants have been successfully installed at hospitals, hostels, restaurants, and other buildings that have combined decentralized systems that look good with efficient systems on their grounds. This shows that they can be used and that they have clear benefits. Therefore, sustainable resolution of India's urban waste management issues depends on encouraging urban participation by employing supportive policies, financial incentives, and lifestyle-friendly technologies.
The conclusion
India's urban garbage management calls for a mixed strategy combining centralized and dispersed solutions. Modern, source-level biogas systems handle the unique challenges of managing organic waste in cities, providing direct and immedi-
ate environmental and financial benefits. Centralized CBG facilities, on the other hand, handle a lot of agricultural and industrial waste well. India can greatly increase urban involvement in distributed waste management by removing obstacles through legislative incentives, technical developments, community education, and effective pilot projects. In the end, this well-rounded approach will guide the country toward sustainable, efficient, cleaner urban living conditions, therefore opening the path for a better and healthier future.
Mr. Rinu Thomas Chief Technology Officer
Vivifica Sustainable Solutions Pvt. Ltd.
Unlocking Carbon Credits: The Role of Biogas
in India’s Low-Carbon Future
Introduction
As India advances toward its 2070 net-zero target, the biogas sector offers a transformative opportunity to integrate sustainable waste management with economic benefits. By converting organic waste—such as municipal waste, agricultural residues, and livestock manure—into clean energy through anaerobic digestion, biogas projects significantly reduce methane emissions while generating carbon credits.
A carbon credit represents the reduction of one metric ton of CO₂ or its equivalent greenhouse gases and can be traded
1: Indian biogas carbon projects & issuances under GS & VCS mechanism
Figure
in carbon markets. Independent third-party auditors verify these emission reductions according to standards such as Verra and Gold Standard, ensuring compliance and credibility. Project developers and investors facilitate funding and operations, while government policies offer regulatory support and financial incentives. Once issued, carbon credits are sold, offering stakeholders economic returns and reinforcing environmental sustainability.
As of December 31, 2024, India is a significant participant in the voluntary carbon market, hosting 92 biogas projects at different phases of the carbon cycle under the Gold Standard (GS) and Verra’s Voluntary Carbon Standard (VCS). These projects have generated over 7.15 million carbon credits, with approximately 4.3 million already retired—equating to an estimated USD 21 million (INR 18.8 crore) in realized value. India, with its extensive agricultural waste resources and a swiftly growing biogas sector, is positioned to emerge as a significant player in global biogas credit markets.
Beyond carbon markets, biogas and biomethane could play a pivotal role in India's energy transition. Replacing just 20% of natural gas with biogas and biomethane could save an estimated USD 29 billion in LNG imports from FY 2025 to FY 2030. Government initiatives, including the rollout of E20 fuel,
the establishment of 500 Wasteto-Wealth plants, and a revised Compressed Bio Gas (CBG) pricing structure, are propelling sector growth. The mandated 5% CBG blending for natural gas companies has further attracted private investments. India's biogas market, valued at USD 1.64 billion in 2024, is anticipated to expand at a CAGR of 10.2%, reaching USD 3.49 billion by 2032.
Biogas Technologies and Carbon Credits
In the global pursuit of sustainable energy, biogas technologies are proving to be transformative tools, these projects not only curb greenhouse gas emissions but also create financial opportunities through carbon credit mechanisms. Beyond mitigating climate impact, biogas initiatives contribute to energy security, improved waste management, and socio-economic development. The following sections highlight key biogas project activities that yield both environmental and economic benefits.
At the grassroots level, household biogas systems are revolutionizing energy access. These small-scale biodigesters utilize organic waste or livestock manure as feedstock, providing a sustainable alternative to traditional biomass fuels like firewood and charcoal. By reducing dependence on non-renewable biomass, they help curb deforestation and lower emissions
from both fuel combustion and organic waste decomposition. The generated biogas serves as a clean cooking fuel, significantly enhancing indoor air quality and minimizing respiratory health risks. These household-level projects qualify for carbon credits by measuring emissions avoided and fossil fuel displacement.
On a larger scale, community and commercial biogas plants handle significant volumes of organic waste, including agricultural residues, food scraps, and livestock manure. These systems not only provide decentralized energy solutions but also offer an alternative to conventional waste disposal methods. Without proper treatment, organic waste in landfills or open dumps releases methane—a greenhouse gas 28 times more potent than CO₂. By absorbing and utilizing this methane, biogas plants prevent harmful emissions while producing a renewable energy source. Additionally, the byproduct—digestate—can be repurposed as an organic fertilizer, reducing the reliance on synthetic alternatives. These projects earn carbon credits through methane avoidance and the displacement of fossil fuel-derived energy.
Industrial-scale biogas projects are further expanding the scope of emission reductions by integrating biogas upgrading technologies. Advanced purification processes enable the conversion of raw biogas into biomethane,
which can be injected into natural gas grids or used as a fuel substitute for industries and transport. This aligns with India’s growing focus on compressed biogas (CBG), which is seen as a strategic fuel alternative under the SATAT initiative. By displacing conventional fossil fuels in hard-to-abate sectors like manufacturing and logistics, these projects not only reduce carbon footprints but also enhance energy independence. The Carbon credits generated from these initiatives contribute to their financial viability while supporting national and global decarbonization goals.
From rural homes to large-scale waste treatment facilities, biogas technologies offer a versatile approach to emission reduction. Their ability to integrate waste management, clean energy production, and carbon finance
makes them a key player in sustainable development. With continued innovation, investment, and supportive policies, biogas projects can play a pivotal role in transitioning toward a low-carbon economy.
Successful Biogas-Based Carbon Credit Initiatives in India
The Bagepalli Biogas Project, developed by ADATS and the Bagepalli Coolie Sangha (BCS), is a trailblazer in India’s clean energy transition. As the first biogas initiative registered under the UNFCCC CDM in 2005, it later achieved Gold Standard certification in 2009, setting a precedent for community-driven climate solutions. Beyond reducing emissions, the project directly distributed over ₹6.23 crore in carbon revenue to participating women, recognizing their role in environmental
stewardship. With every Rupee reinvested into the community, this initiative not only promoted sustainable energy but also empowered rural women, becoming a model for socially inclusive climate action.
Meanwhile, Dudh Utpadak Sahakari Sangh Limited (DUSSL) in partnership with NDDB MRIDA has initiated a carbon project focused on methane recovery through controlled anaerobic digestion of animal waste (cow dung). The recovered methane (biogas) is utilized for thermal energy and electricity generation within the dairy plant. This initiative is expected to mitigate approximately 145,000 tCO₂ emissions over seven years. By replacing conventional fuel sources, the project promotes renewable energy generation while contributing to sustainable development goals.
Figure 2: Types of biodigesters
Environment
India’s Policy Framework for Biogas and Carbon Markets
India's policy framework has played a crucial role in advancing biogas adoption and integrating it into carbon markets. The National Bioenergy Programme (NBP), launched by the Ministry of New and Renewable Energy (MNRE), supports biomass-to-energy projects with financial assistance from 2021-22 to 2025-26. The SATAT initiative aims to create a comprehensive ecosystem for Compressed Biogas (CBG) production, offering long-term offtake agreements, bio-manure inclusion in the Fertilizer Control Order, and Priority Sector Lending classification. Meanwhile, the GOBARdhan initiative focuses on converting biodegradable waste into biogas, CBG, and organic manure, with 536 CBG and 1,193 biogas plants registered as of June 2023,in addition to significant strategies to entice private participation.. The Waste to Energy scheme, under the Central Financial Assistance (CFA) program, provides capital subsidies for large-scale biogas projects that recover energy from waste.
In late 2022, India amended the Energy Conservation Bill to introduce a domestic carbon credit trading scheme. CBG projects are now eligible for mitigation activities for carbon trading within India. Under the Paris Agreement, these projects can participate in both Article 6.4 and Article 6.2 mechanisms. Article 6.4 facilitates carbon trad-
ing between public and private entities through international carbon markets, whereas Article 6.2 allows countries to trade Internationally Transferred Mitigation Outcomes (ITMOs) bilaterally or multilaterally to meet their Nationally Determined Contributions (NDCs). This means that credits generated by CBG projects will directly contribute to India’s greenhouse gas reduction targets under the Paris Agreement.
Together, these policies have driven the expansion of biogas initiatives across India, positioning biogas as a key pillar in the country's decarbonization strategy.
Conclusion
Despite challenges in project eligibility and market integration, the biogas sector offers significant opportunities for economic incentives, emissions reduction, and sustainable development. It remains a vital part of India’s strategy to achieve its climate targets.
India stands at a crucial juncture where sustainability and economic growth must coexist. By transforming waste into
a valuable resource, biogas can drive rural empowerment and industrial sustainability. With advancements in technology, supportive policies, and well-integrated carbon markets, India has the potential to lead the global biogas-driven carbon credit sector. Investing in biogas today paves the way for a greener, more resilient future.
Director-Projects
Mr. Nagaraju Bellapu
Recommendation to Boost the CBG Industry-Reaction
on Union Budget 2025
With a strong push for manufacturing, green energy, and digital transformation, this budget sets the stage for an Atmanirbhar and Viksit Bharat. Specifically from the standpoint of the fledgling biogas/CBG industry, the announced increase to the MSME Credit Guarantee Scheme will significantly benefit the biogas industry, which often faces challenges in securing credit with reasonable terms. By expanding the credit guarantee cover from ₹5 crore to ₹10 crore, the scheme ensures easier access to collateral-free loans thus reducing financial barriers for the CBG developers. Additionally, the revised MSME classification criteria allow for almost 2-2.5 times higher investment and turnover limits than the earlier regime.
The amendment ensures that even larger capacity CBG projects are now eligible for these incentives.
While the recent budget takes adequate steps to support the MSME sector, the inclusion of specific policy measures for the CBG industry would have made it even more conducive for the sector. Therefore, to foster the growth of the biogas and Compressed Biogas (CBG) producers and enhance the sector’s longterm viability, certain policy frameworks need to be devised and implemented.
IBA recommends creating a framework which enables biogas plant promoters to sell carbon credits on both international and
Advisory domestic platforms. This would not only aid the Indian government with its climate change targets but would also open up different revenue channels for producers as well. Furthermore, the legislation regarding Renewable Energy and Green Certificates’ tokenization and trading should be hastened to maximize clean energy projects' profitability. Presently, trading of carbon credits in the voluntary carbon market is priced at approx. USD 5 to 50 per unit (1 ton of CO2). Even at the lowest pricing of USD 5 per ton of CO2, the carbon price premium of CBG for its GHG mitigation effect is estimated to be in the range of around INR 10-12 per kg of methane produced. Such realization of additional revenue shall raise the financial viability of the biogas/CBG projects significantly. GOI should consider implementing either cap and trade practices (buy green certificates if the allocated GHG quota is overshot) for carbon-intensive entities and also subsidise a portion of the above-proposed carbon premium price to kick-start the process. It is also recommended that the certification and trading process should be practically simple to ensure that the export possibilities of these business aspects can be fully exploited.
Furthermore, it would be prudent for the government to put in place measures to cover the transportation or mobilization of feedstock such as crop residues like paddy straw from the farms and local aggregators to the
biogas plants. Indian farmers’ and biogas producers’ earnings would be improved financially enabling them to assist in biogas production through subsidies of INR 1-3/kg paid to them as transportation costs of the residues. The state of Haryana presently offers INR 1000 per acre to farmers who refrain from burning paddy in a bid to combat air pollution. This scheme should be scaled up and rolled out in a phased manner across the country. The states with high agricultural residue such as Punjab, Haryana, Uttar Pradesh and Bihar should be the first to implement the phase style strategy and thereafter can be expanded over other parts of the country. Such blanket policies will exude confidence amongst investors, encouraging intermediary business activities spanning agricultural waste collection and transportation. In addition to encouraging biogas generation, this will also help farmers gain additional income thus aiding the economy of the country and supporting the targets of sustainable emissions reduction.
A complete tax waiver should be introduced for CBG producers, which provides tax relief in the initial years of operation. This will act as a huge incentive for businesses that are willing to
invest in and scale up CBG production, contributing to cleaner energy generation. In FY24-25, with a total of around 100 functional commercial CBG plants in India, at its full capacity utilization, upon considering a complete tax waiver, the govt would relinquish an estimated INR 100 crores in tax revenue. This shortterm dent in the exchequer will aid in long-term growth for the renewable energy sector. This action will attract private investments, and new job creation and enable meeting India’s renewable energy targets.
Overall, the recently presented Indian budget is a consumption-driven blueprint that gives the economy a much-needed push by increasing domestic demand, improving credit access, and encouraging entrepreneurship. By strengthening MSME and start-Up financing, a facilitating pipeline for infrastructure investments, and putting more money in the hands of consumers through tax breaks, the budget ensures a multiplier effect of the incentives provided, resulting in a perfect panacea for driving consumption-led economic growth and thereby kicking off the virtuous cycle of capacity expansion and job creation.
Meet the Author
Mr. Abhijeet Mukherjee Director-Operation Indian Biogas Association
The Netherlands Innovation Network supports Dutch researchers and tech companies in advancing bioenergy solutions that contribute to a sustainable carbon cycle. We focus on renewable energy for transport and industry, supporting innovation through global partnerships like Mission Innovation and Horizon Europe. Our goal? A cleaner, circular economy driven by smart, sustainable tech.
Sh.
PEDA supports bioenergy development to tackle not only the ever-increasing energy demand of the state but also recognizes its importance for the handling of waste challenge, reducing stubble burning, enhancing air quality, and generating clean energy. Biogas and CBG boost rural economies and promote a sustainable, green future.
OPINION
Sustainability and bioenergy are at the heart of Muni Seva Ashram’s vision for a greener future. Embracing renewable resources, we strive to harmonize technology with nature, promoting energy solutions that empower communities while preserving the environment. Together, we pave the path towards a sustainable, self-reliant tomorrow.
We recognize the vital role of ESG principles in shaping a sustainable future. Bioenergy stands as a beacon of innovation, aligning economic growth with environmental responsibility. By embracing bioenergy, India can foster sustainable practices that drive impactful change, balancing profit, people, and the planet.
Dr. Vikram Patel, Muni Seva Ashram
Prof. Amit Garg, IIM Ahmedabad
M P Singh, PEDA
Sh. Arun Thekkedath, Netherlands Innovation Network, India
Membrane separators for Biogas upgrading and dehydration
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A Comparative Analysis of
Kalundborg, Swedish Biogas, and Hamburg Biogas
Biogas technology plays a critical role in promoting renewable energy systems by providing both sustainable energy and waste management solutions. This article explores three significant biogas initiatives: the Kalundborg Symbiosis in Denmark, Swedish Biogas' national strategies, and Hamburg Biogas in Germany. It compares their technological approaches, integration strategies, and waste management practices, aiming to highlight success factors, identify challenges, and explore the future potential of biogas.
Kalundborg Symbiosis: A Model of Industrial Symbiosis
The Kalundborg Symbiosis in Denmark offers a pioneering example of an industrial ecosys-
tem where waste from one company becomes a resource for another. This symbiosis involves several major industrial players, including a power plant, a pharmaceutical company, a refinery, and a plasterboard manufacturer. Waste streams such as excess heat, wastewater, and other byproducts are shared, forming a closed-loop system that reduces environmental impact while optimizing resource use.
In Kalundborg, biogas is primarily produced through the anaerobic digestion of agricultural and industrial organic waste. This biogas is used for generating electricity and heat, significantly reducing reliance on fossil fuels. The standout feature of this system is its integration of waste recycling, which not only lowers costs for participating compa-
Case Study
nies but also promotes sustainability by reducing emissions and waste generation. Kalundborg’s success underscores the potential for biogas in fostering circular economies.
The key environmental benefit of Kalundborg is its ability to reduce greenhouse gas emissions and minimize landfill waste, thus promoting resource efficiency. The symbiosis fosters continuous innovation, with the interconnectivity of industries driving new solutions to sustainability challenges. Kalundborg sets a precedent for other industrial clusters aiming to adopt sustainable and waste-minimizing practices.
Swedish Biogas: A National Commitment to Sustainability
Sweden has firmly positioned itself as a leader in biogas technology, supported by strong national policies aimed at sustainable energy transitions. The Swedish Biogas Association plays a key role in advancing the production and use of biogas, focusing on diverse feedstocks such as agricultural residues, municipal waste, and wastewater sludge. Technological advances in anaerobic digestion and biogas upgrading have significantly improved the efficiency and economic viability of Swedish biogas production.
A major focus of Sweden’s strategy is biogas as a transportation fuel. Biogas-powered vehicles, including buses, trucks, and pas-
senger cars, have grown in popularity, helping to reduce fossil fuel consumption and mitigate greenhouse gas emissions. Sweden has also heavily invested in biogas upgrading technologies, such as membrane separation, to produce high-quality biomethane that can be injected into the natural gas grid. This integration of biogas into the national energy infrastructure not only enhances energy security but also diversifies Sweden’s energy sources.
The Swedish success can be attributed to a combination of government incentives, strong public-private partnerships, and significant investments in biogas infrastructure. This holistic approach, including research and development, infrastructure improvement, and favorable policy frameworks, has positioned Sweden as a frontrunner in renewable energy technology.
Hamburg Biogas: Urban Waste Management and Energy Integration
Hamburg Biogas, located in Germany, represents an excellent example of biogas integration in an urban setting. The city has strategically developed biogas production from organic waste generated by households, restaurants, and industrial sectors. The biogas plant is located near waste processing facilities, which optimizes the collection and transport of organic waste and reduces associated greenhouse gas emissions from hauling.
Advanced anaerobic digestion technologies are employed to maximize biogas production from the waste feedstock. The biogas is then upgraded to biomethane, which is injected into the natural gas grid to provide a renewable energy source for Hamburg’s homes and businesses. Additionally, the biogas plant integrates waste management techniques like composting and nutrient recovery, further reducing landfill use and promoting resource recycling.
Hamburg Biogas highlights the feasibility of embedding biogas production into urban infrastructure. The project reduces waste, generates renewable energy, and improves air quality by reducing reliance on fossil fuels. Hamburg’s experience emphasizes the importance of strategic planning, innovation, and collaboration between public and private sectors in achieving urban sustainability goals.
Comparative Case Study:
Success Factors and Challenges
The comparison of Kalundborg, Swedish Biogas, and Hamburg Biogas uncovers several critical success factors and challenges. Kalundborg’s industrial symbiosis and closed-loop system provide exceptional resource optimization and waste reduction. However, replicating this model in other regions poses a challenge due to its complexity and
reliance on multiple industries. Swedish Biogas benefits from robust governmental support and technological innovation but faces challenges in scaling up production to meet growing energy demands. Hamburg Biogas, on the other hand, demonstrates the effective integration of biogas into urban waste systems but requires meticulous
coordination to manage diverse organic waste streams and ensure efficient operation.
Despite their differences, the key success factor common to all three cases is stakeholder collaboration. Effective partnerships between industry, government, research institutions, and communities are crucial for
securing funding, fostering innovation, and promoting biogas technologies. Another common success factor is the use of advanced biogas production technologies, which maximize efficiency and output. Overcoming challenges related to feedstock supply, infrastructure, and regulatory frameworks is vital for widespread adoption.
Conclusion: Biogas' Potential for the Future
Biogas holds considerable promise as a renewable energy source and an effective waste management solution. The case studies from Kalundborg, Swedish Biogas, and Hamburg Biogas demonstrate how biogas production can be successfully implemented in various contexts, from industrial symbiosis to urban waste integration. Each initiative has shown that biogas can reduce greenhouse gas emissions, improve resource efficiency, and contribute to energy security.
The future of biogas lies in enhancing the efficiency of an-
aerobic digestion processes, advancing biogas upgrading technologies, and integrating biogas into smart energy grids. To unlock its full potential, it is essential to foster supportive policy environments, encourage public-private partnerships, and invest in research and innovation. Government incentives like tax credits, feed-in tariffs, and public awareness campaigns will be pivotal in stimulating further biogas production and usage.
As the global push for a low-carbon economy grows, biogas will play an increasingly important role in diversifying the energy mix and supporting sustainable waste management solutions. Harnessing organic waste through biogas can lead to a cleaner, more sustainable future, benefiting both local communities and the broader global ecosystem.
Meet the Author
Mr. Tarun Kumar Director Integri Marine and Offshore Service Pvt. Ltd.
Aspect
Kalundborg (Denmark)
Swedish Biogas (Sweden)
Hamburg Biogas (Germany) Core
Hydrogen Sulfide in Biogas:
Generation and abatement guide
Hydrogen sulfide (H₂S) is a natural byproduct of anaerobic digestion in biogas production. During this process, organic matter is broken down by microorganisms in the absence of oxygen. H₂S is generated when sulfur-containing compounds in the feedstock are reduced. Here’s a brief overview of how this happens:
Sources of Hydrogen Sulfide in Biogas:
1. Sulfur-Containing Feedstock:
o Organic materials such as manure, sewage sludge, food waste, and agricultural residues
often contain sulfur compounds (e.g., proteins, sulfates, and sulfites).
o During anaerobic digestion, these sulfur compounds are converted into H₂S.
2.Sulfate-Reducing Bacteria (SRB):
o SRB, such as Desulfovibrio and Desulfotomaculum, play a key role in H₂S formation.
o These bacteria reduce sulfates (SO₄²⁻) and other sulfur compounds to H₂S in the absence of oxygen:
3.Decomposition of Organic Sulfur Compounds:
o Proteins and amino acids (e.g., cysteine and methionine) in the feedstock are broken down by hydrolytic and acidogenic bacteria, releasing H₂S.
Factors Influencing H₂S Formation:
1. Feedstock Composition:
o High sulfur content in feedstock (e.g., manure, certain industrial wastes) leads to higher H₂S production.
2. Digester Conditions:
o pH: Neutral to slightly alkaline conditions favour H₂S formation.
o Temperature: Mesophilic (3040°C) and thermophilic (5060°C) conditions can influence microbial activity and H₂S production.
o Retention Time: Longer retention times may increase H₂S formation.
3. Microbial Activity:
o The presence and activity of sulfate-reducing bacteria (SRB) directly impact H₂S levels.
Hydrogen sulfide formation in biogas is a natural process driven by the breakdown of sulfur-containing compounds during anaerobic digestion. Proper management and treatment are essential to mitigate its negative effects and ensure safe biogas utilization.
Below are some of the processes widely used for abatement of hydrogen sulfide in the industry.
1. Chelated Iron Process:
The Chelated Iron Process is a chemical method used for biogas desulfurization, specifically to remove hydrogen sulfide (H₂S) from biogas. This process is particularly useful in anaerobic digestion systems, where biogas produced contains H₂S, a corrosive and harmful to equipment and the environment. The chelated iron process is efficient, cost-effective, and environmentally friendly.
How the Chelated Iron Process Works:
1. Oxidation of H₂S:
o Biogas containing H₂S is passed through a scrubbing solution containing chelated iron (Fe³⁺)
o The chelated iron acts as an oxidizing agent, converting H₂S into elemental sulfur (S⁰) and water (H₂O):
2.Regeneration of Chelated Iron:
o The reduced iron (Fe²⁺) is then regenerated back to its oxidized form (Fe³⁺) by introducing oxygen (air) into the solution:
o This regeneration step allows the chelated iron solution to be
reused, making the process sustainable.
3. Sulfur Recovery:
o The elemental sulfur formed during the process is separated from the solution, typically by filtration or settling.
o The recovered sulfur can be further processed or disposed of safely.
Key Features of the Chelated Iron Process:
• High Efficiency: Capable of removing >99% of H₂S from biogas.
• Selective: Targets H₂S without affecting other biogas components like methane (CH₄).
• Regenerative: The chelated iron solution is continuously regenerated and reused.
• Environmentally Friendly: Converts H₂S into non-toxic elemental sulfur, which can be reused or safely disposed of.
• Operational Flexibility: Can handle varying H₂S concentrations and biogas flow rates.
The chelated iron process is a reliable and sustainable solution for biogas desulfurization, ensuring compliance with environmental regulations and protecting downstream equipment from H₂S-related damage.
2. Alkali Scrubbing for Biogas Desulfurization
Alkali scrubbing is a chemical process used to remove hydrogen sulfide (H₂S) from biogas. It involves passing biogas through an alkaline solution, such as sodium hydroxide (NaOH), or sodium carbonate (Na₂CO₃), which reacts with H₂S to produce non-volatile compounds.
a. Key Points:
i. Reaction:
ii. H₂S reacts with the alkali to form sulphides or bisulfides:
b. Process:
i. Biogas is introduced into a scrubbing tower bottom where alkali solution is sprayed from the top of the column, in a counter-current flow for better contact. These counter-current columns are typical of the packed type.
ii. H₂S is absorbed and chemically converted, leaving the biogas clean.
c. Advantages:
i. High H₂S removal efficiency (up to 99%).
ii. Simple and cost-effective for small to medium-scale applications.
iii. Can be regenerated in some systems.
d. Disadvantages:
i. Alkali consumption requires periodic replenishment.
ii. Spent solution disposal or treatment is needed.
iii. pH control is critical for optimal performance.
e. Applications:
i. Used in biogas upgrading for renewable natural gas (RNG), wastewater treatment, and agricultural/industrial biogas systems.
ii. Alkali scrubbing is a reliable and efficient method for biogas desulfurization, ensuring safe and clean biogas for energy use.
3. Ferrosorp-Based Biogas Desulfurization
Ferrosorp is a dry desulfurization method that uses iron oxide (Fe₂O₃) or iron hydroxide (Fe(OH)₃) based adsorbents to remove hydrogen sulfide (H₂S) from biogas. It is a simple, cost-effective, and widely used technique, especially for small to medium-scale biogas systems.
Key Points:
1. Mechanism:
o H₂S reacts with iron oxide/hydroxide to form iron sulfide (FeS) or iron disulfide (FeS₂):
o FerroSorp with oxygen in biogas and relative humidity of about 90% provides 2-3 times more loading rate and in situ regeneration of catalyst which significantly brings down the overall cost of operation.
2. Process:
o Biogas is passed through a bed of Ferrosorp material (e.g., pellets or granules).
o H₂S is adsorbed and chemically bound, leaving the biogas clean.
3. Advantages:
o Simple and easy to operate with no liquid waste.
o High H₂S removal efficiency (up to 99%).
o Low maintenance and suitable for small-scale applications.
4. Disadvantages:
o Adsorbent is consumed and needs periodic replacement.
o Limited capacity for high H₂S concentrations or large biogas volumes.
o Spent material requires proper disposal.
5. Applications:
o The reaction is irreversible without air, and the adsorbent is consumed over time.
o Commonly used in agricultural biogas plants, small-scale digesters, and wastewater treatment
facilities.
Ferrosorp-based desulfurization is a reliable and efficient method for removing H₂S from biogas, ensuring safe and clean biogas for energy production.
4. Biochemical Process:
The Biological Desulfurization Process is a sustainable and efficient method for removing hydrogen sulfide (H₂S) from biogas using sulfur-oxidizing bacteria. This process is widely used in anaerobic digestion systems, landfill gas treatment, and other biogas-producing facilities. It is an environmental friendly alternative to chemical desulfurization methods.
How the Process Works:
1. Absorption of H₂S:
o Biogas containing H₂S is introduced into a scrubber (e.g., a packed column or bubble column).
o The H₂S is absorbed into an alkaline scrubbing solution (typically sodium hydroxide, NaOH, or sodium carbonate, Na₂CO₃), forming a sulfide-rich solution:
(S⁰) or sulfate (SO₄²⁻) in the presence of oxygen:
o The process can be controlled to favour the production of elemental sulfur, which is easier to handle and has commercial value.
o The scrubbing solution, now free of sulfide, is regenerated and recycled back to the absorber for reuse.
3. Sulfur Recovery:
o Elemental sulfur is separated from the bioreactor effluent by settling or filtration.
o The recovered sulfur can be used as a raw material in various industrial applications or agricultural applications.
Key Features of the Biochemical Scubbing Process:
•High Efficiency: Removes >99% of H₂S from biogas.
•Environmentally Friendly: Uses natural biological processes and produces minimal waste.
•Cost-Effective: Low operating
costs due to the use of renewable biological catalysts.
• Selective: Targets H₂S without affecting methane (CH₄) or other biogas components.
• Flexible: Can handle varying H₂S concentrations and biogas flow rates.
Every biogas purification process has an optimal operating range where the total cost of ownership (TCO) is minimized. This optimal range varies depending on the biogas flow rate and hydrogen sulfide (H₂S) concentration. The primary determinants influencing H₂S removal technology selection are the H₂S loading and downstream processing requirements.
To assist in technology selection, we've developed a guide that recommends the solution with the lowest TCO. Our TCO calculation includes capital expenses and operating costs projected over a 20-year plant lifespan. We advise users to focus on the trends in TCO rather than absolute numbers, as the trends remain consistent regardless of the specific calculation method.
2. Biological Oxidation:
o The sulfide-rich solution is transferred to a bioreactor containing sulfur-oxidizing bacteria (e.g., Thiobacillus species).
o These bacteria oxidize the sulfide (HS⁻) to elemental sulfur
