Domestic Biogas Research Articles

From failure to fairness: A call for accountability within household biogas development

The purpose of this perspective piece is to advocate for a paradigm shift in biogas research, and argues for the need to centre accountability and justice in household biogas development research and discussion Drawing from biogas literature and the authors' own experiences in South Asia and Southern Africa, the perspective illustrates how a lack of accountability in biogas programmes has led to negative outcomes and harm to beneficiaries of top-down biogas programmes. The article emphasises the critical need for a research agenda that prioritises accountability and justice, particularly in the context of the increasing number of biogas installations driven by carbon credits and international aid. It proposes a dual approach: firstly, an in-depth analysis of the impacts of accountability deficits in biogas projects; and secondly, strategies for effectively embedding accountability into programme design. The perspective also advocates for incorporating restorative justice principles in domestic biogas research, starting from project initiation, to ensure there are plans for amending the harm caused should projects fail to achieve their intended outcomes. This approach is essential for holding governments and institutions accountable in large-scale biogas installation. The perspective concludes with a call for an overhaul of the aid and biogas sectors, highlighting the necessity for systemic solutions and a more profound engagement with the practical challenges of biogas implementation.

Advances in mixed-matrix membranes for biorefining of biogas from anaerobic digestion.

This article provides a comprehensive review of the state-of-the-art technology of polymeric mixed-matrix membranes for CO2/CH4 separation that can be applied in medium, small, and domestic biogas systems operating at low pressures (0.2-6kPa). Critical data from the latest publications of CO2/CH4 separation membranes were analyzed, considering the ratio of CO2/CH4 permeabilities, the CO2 selectivity, the operating pressures at which the membranes were tested, the chemistry of the polymers studied and their gas separation mechanisms. And the different nanomaterials as fillers. The intrinsic microporous polymers (PIMs) were identified as potential candidates for biomethane purification due to their high permeability and selectivity, which are compatible with operation pressures below 1 bar, and as low as 0.2 bar. This scenario contrasts with other polymers that require pressures above 1 bar for operation, with some reaching 20 bar. Furthermore, the combination of PIM with GO in MMMs was found to not influence the permeability significantly, but to contribute to the membrane stability over time, by preventing the structural collapse of the membrane caused by aging. The systematic analysis here presented is a valuable resource for defining the future technological development of CO2/CH4 separation membranes for biogas biorefining.

Current Status and Future Prospects of Small-Scale Household Biodigesters in Sub-Saharan Africa

Despite the age of the technology, sub-Saharan African (SSA) countries have numerous challenges that hinder biogas from being widely adopted. This review investigates the current gap between holistic use and the need for small-scale household biodigester adoption and effectiveness in rural and semiurban households of SSA. It reviews the present situation and potential of small-scale household digesters for sustainable future energy and biofertilizer use, with a focus on SSA. A literature survey was performed on small-scale household biogas digesters, and issues relating to the distribution, use, and implementation status with their implications on the future of small-scale household digesters in SSA were briefly reviewed. In recent years, the overall number of domestic biogas digesters installed across SSA countries has shown a significant increase due to the efforts of the National Domestic Biogas Programs such as the African Biogas Partnership Program with the Netherlands Development Organization and the Humanist Institute for Development Cooperation. However, based on an extensive literature review on small-scale household biodigesters in SSA, the study highlights that the success of biogas technology as a clean domestic cooking fuel has been relatively low. The findings of this review show that SSA countries still face a number of hurdles, the most significant of which can be boiled down to the need for technological advancement according to local context, social acceptance, and large initial investment costs. In order to overcome these obstacles and advance technological capability, social acceptance, financial benefits, and environmental impacts in order to improve its use and widespread dissemination as a renewable energy source, a highly effective organic fertilizer, and economic benefits for the betterment of SSA communities, more well-organized work and adequate research activities should be initiated and supported. The findings may be useful to researchers, practitioners, and policymakers who support/promote sustainable energy and waste management strategies in low-resource settings.

Developing slow-release fertilizer based on pyrolysis of domestic biogas digestate cake: A circular economy approach for rural farmers

The scientific community is becoming more interested in biochar-based slow-release fertiliser (BSRF) as a solution to the problems with ready-to-use fertilisers, such as limited plant uptake and nutrient leaching when applied to soils. Dependency on chemical fertilizer can also be subsidized through BSRFs under waste-to-wealth approaches. In this study, we prepared the BSRFs using anaerobic digestate (AD) and for that, the solid residues and press liquid were separated from AD and the solid part was pyrolysed at 350 °C (ADB350) and 500 °C (ADB500) after blending with Ca-bentonite (25%). Charred biomass was impregnated with press liquid to prepare respective modified BSRFs. SEM−EDS, XRD, and FT-IR analysis suggested significant changes in surface morphology and chemical characteristics of ADBs. ADBs were examined for their slow-release behaviour and plant nutrient (N, P and K) uptakes by wheat (Triticum aestivum) seedlings using a pot setup. To be specific, the respective release ratio for N, P, and K in the initial 10 d of the ADBs incubation study was 78.90%, 57.55%, and 80.50% for ADB350 and 59.80%, 42.50%, and 55.60% for ADB500. Slow-release performance exhibited synchronization well with the growth and biomass yield in wheat seedlings. Plant uptake results revealed significant utility (mg/pot) of N (63.0 ± 2.04), P (1.58 ± 0.37) and K (64.0 ± 5.8) suggesting the slow-release behaviour of ADBs. In summary, pyrolysed AD could be utilized efficiently as an environmental-friendly and low-cost fertilizer for sustainable crop production.

Anaerobic Digestion (AD) Based Waste Management in Nepal: Technologies and Implementation Modalities

Developing countries are still facing severe challenges for providing access to clean energy, managing waste and struggling to meet Sustainable Development Goals (SDG) targets. Anaerobic Digestion (AD) based waste management technologies have great potential for addressing these challenges. Public Private Partnerships (PPP) are the key government's policy and strategic directions for promoting biogas as a multi-beneficiary's product and services in Nepal. Nepal's biogas promotion PPP model and technologies in domestic biogas sector have been replicated in many African and Asian countries. AD based Gobar Gas Company (GGC 2047 model) and Continuously Stirred Tank Reactor (CSTR) based technologies have been promoted for domestic and large applications respectively in wider scale. Comprehensive review and analysis using technological and implementation progress results through government interventions revealed that with the potential of 1.1 million of domestic biogas 433,173 systems have been installed. Quantification of outcomes of AD based technologies revealed that in addition to the energy access to more than 1.8 million people, these significantly contributed for production of gas amounting 456,282 m3 and substituted equivalent 15,578 nos. of LPG cylinders and 2229.91 tons of fertilizer daily. Under Carbon Development Mechanism (CDM), Total 21.20 million USD have been earned as carbon revenue from this sector, which has played significant role for earning revenue from carbon financing. Similarly, Developing Carbon Program for Large Scale Biogas through ITMO (Internationally Transferred Mitigation Outcomes: a new carbon mechanism) is under way. Overall, biogas sector is contributing for country' s energy security and circular economy through replacement of fossil fuels and chemical fertilizers along with the waste management.

Cellular concrete waste: An efficient new way for H2S removal

The ability of cellular concrete waste (CC) to remove hydrogen sulfide (H2S) from a mimic biogas composed of nitrogen, oxygen and H2S was investigated using abiotic filtration systems for H2S concentration up to 1500 mg m−3 and Empty Bed Residence Time (EBRT) ranging from 30 to 180 s. The influence of the humidity of the material in H2S removal was studied. In wetted conditions (relative humidity > 97 %), 169 g of H2S were removed per kg of material. This value is probably lower than the maximum capacity of the cellular concrete since the experiment was ended before the end-of-life of the material. The H2S elimination capacity of cellular concrete waste could reach up to 32 g m-3 h−1. These performances are due to complex physico-chemical mechanisms operating simultaneously between H2S and the different components of cellular concrete (mainly calcium oxide CaO from the calcium silicate hydrate CaO SiO2 nH2O, and ferric oxide Fe2O3) leading to a modification of the mechanical structure of the material to calcium sulfate (gypsum CaSO4 2H2O) and the production of elemental sulfur (octasulfur S8). Empirical relationships based on H2S concentration and EBRT were established (i) to predict the Removal Efficiency (RE) of the filtration system (logistic equation); (ii) to assess the operating time of the material. Results obtained suggest that this simple, robust and cheap H2S removal technology would be a suitable and valuable technique to treat gas flowrates generated by decentralized domestic biogas digesters.

Assessing energy sources for powering “evakuula”

Technologies that are appropriate, affordable, and sustainable are needed to increase incomes and resilience among sub-Saharan African smallholder farmers. A combination of thermization and low-cost evaporative cooling, termed Evakuuling, was developed to enable rural smallholder dairy farmers to preserve their evening milk in the absence of grid-electricity. The “EvaKuula” was configured to be powered by biogas. Biogas is used for the thermization process of the system. The evaporative cooling component is powered by wind. Use of biogas from domestic biogas plants add circularity value to smallholder farms. However, domestic biogas plant set-ups are relatively high capital investments and as such, a financial barrier to co-adoption with the EvaKuula. To lower this barrier, other energy sources have been considered. The purpose of this study was to assess alternative energy sources to power the thermization component of the EvaKuula. The list of energy sources considered included biogas, butane, kerosene, charcoal, and firewood. These energy sources were assessed with respect to the sum of the social and market costs. The product of a unit of fuel cost and the units consumed represented the “market cost.” The product of the long-term social carbon cost and total carbon dioxide emission equivalence represented the “social cost.” Regular and improved stoves were included in the charcoal and firewood analysis. As expected, biogas ranked on top of the list, followed by butane and kerosene. However, butane and kerosene are not easily accessible in rural setting. Approximated 76% of farmers in rural sub-Saharan Africa rely on firewood to meet domestic needs like cooking. Butane and kerosene are the fuel sources predominantly used in urban and peri-urban areas, due to accessibility and affordability. Incomes are typically higher among urban dwellers. Therefore, with butane and kerosene not readily available to the target EvaKuula users, the next best option was firewood, provided it is combusted in improved efficient stoves such as Lorena type. Key words: alternative energy, evaporative cooling, sustainable development, food security, circularity, smallholder farmers

Challenging perceptions of socio-cultural rejection of a taboo technology: Narratives of imagined transitions to domestic toilet-linked biogas in India

Domestic toilet-linked anaerobic digesters (TLADs) recycle organic waste materials, including human excreta (HE), into a clean gaseous fuel and fertiliser product. Socio-cultural resistance is often used to explain local resistance towards TLADs due to the use of HE as a feedstock. However, through qualitative investigation utilising in-depth semi-structured interviews with potential TLAD users in Assam, India, the use of socio-cultural rejection to describe resistance towards TLADs was found to have homogenised local voices and framed them as resistant to technological change whilst ignoring diversity within groups. The narratives revealed resistance to be diverse and related to an individual's place, personal and social identity. Resistance to TLADs results from both socio-cultural as well as socio-technical concerns and is also potentially negotiable. Adoption of TLADs could be facilitated through opportunities such as technology demonstration, social group adoption and a greater perceived necessity. Inefficiencies in Assam's biogas implementation programme have been potentially overlooked due to too much attention being placed on household decision making and generalising socio-cultural resistance across the state. If TLADs are to be disseminated within Assam, authorities must work with communities and employees of the biogas programme to more widely renegotiate social norms around HE as a resource and not a waste product. More generally Assam's biogas programme is ineffectively identifying households with a need and motivation for domestic biogas and we recommend revaluating the use of local contacts to identify households eligible for the national subsidy as well as the bias towards households with large numbers of cattle.

Technological, Economic, Social and Environmental Barriers to Adoption of Small-Scale Biogas Plants: Case of Indonesia

By 2025, biogas is estimated to become a larger part of Indonesia’s energy mix. Biogas is a renewable energy source that also has economic and environmental advantages. Domestic biogas generation has been embraced in Indonesia as a response to the country’s energy security concerns in rural areas. Since the 1970s, 48,038 biogas plants have been built in the region. To fully develop this technology, Indonesia must discontinue relying on fossil fuels and substitute current fossil-fuel-based energy. This article provides an overview of renewable technology in Indonesia, as well as addressing domestic energy demands and referring to existing literature on the socio-technical and socio-economic barriers to biogas adoption in Indonesia. Based on a rigorous review of 71 publications published in Web of Science (WoS) between 2010 and 2021, this study explores existing barriers for biogas adoption by summarizing the current literature from technical, economic, social and environmental perspectives. Biogas adoption is a complex process with many interwoven components. Therefore, this research addresses a gap in the strategic planning and implementation process, providing policymakers with pathways to eliminate bottlenecks in renewable energy planning. Recommendations for future research are also proposed.

State and development of anaerobic technology for biogas production in Syria

The last few decades have seen an increase in the use of Biogas technology around the world. As a result, the advantages of domestic biogas digesters has become more tangible. In the developing world, however, its use has not been yet utilized on a large scale. In this study, we evaluate the productivity of different small-scale biogas installations in Syria in terms of different factors, including temperature, pH, different values of adding cow's manure and hydraulic retention time. We find that these factors can provide a useful adviser for specialists engaged in spreading of household biogas. Consequently, we highlight the need to disseminate biogas technology as a renewable energy source in the countryside, which form a big challenge for the application of biogas technology in the country. We believe that dissemination will solve the problem of rural supply of biogas and reduce the dependence on timber, thus contributing to better environmental protection in Syria. • Biogas technology has led to the adoption of many household biogas reactors. • In the developing world, biogas has only been slightly utilized, due to its effectiveness uncertainty. • We evaluate the productivity of small biogas installations in Syria based on many factors. • These factors provide a useful source for specialists in spreading of household biogas. • Disseminating biogas technology in Syria can help improve environmental protection.

Design And Fabrication of a Domestic Biogas Unit for Cooking Applications

This paper presents the design and fabrication of a domestic biogas unit by using daily organic waste for cooking. Basically, this unit consists a gas storage unit and a digester barrel. Initially, the organic wastes including kitchen wastes were deposited into the digester barrel which contains water with pH 6 once in every two days for two weeks. Then the mix started to produce biogas when the pH value reached around 6.8-7.5. After that food wastes were added slowly every day. When this step is continued further, the daily collection of biogases is 50 liters. As the digestate of this anaerobic digester is rich in nutrients this is also a good organic fertilizer for plants in the home garden. Also, this unit is designed and fabricated with easy maintenance and usage. Further, it is very much beneficial to dispose biodegradable kitchen wastes in an eco-friendly manner. In order to answer the energy demand in domestic level, it is highly essential to utilize the daily organic waste as a source of energy and produce methane as an alternative solution for cooking-energy requirement.

Economic contributions and synergies of biogas with the SDGs in Ethiopia

Domestic biogas technology helps to foster sustainable development in different ways. It is particularly important in countries like Ethiopia where about 80% of the population lives in rural areas, and more than 90% of the households use solid biomass for cooking. In light of this, the Government of Ethiopia has launched a National Biogas Programme in 2008. The Programme, now in its third phase, has successfully installed tens of thousands of biogas digesters. This paper aims to give a macroeconomic insight on the role of the biogas sector in Ethiopia. The annual gross value of biogas outputs reached USD 7.7 million in 2015/16. Installing biogas digesters contributes USD 1.4 million each year to the construction industry. Results of the study indicate that the micro and macroeconomic contributions of biogas sector partly rely on the effective utilization of its co-product (i.e., the slurry) as fertilizer. Agricultural policies of the country should therefore highlight and link domestic biogas production with the extension services.

Development of an innovative MFC-biosensor for real-time monitoring of anaerobic digestion for biogas production: Controlled substrate feeding strategy

A microbial fuel cell (MFC) based biosensor was designed to monitor volatile fatty acids (VFAs) in anaerobic digestion (AD) to control substrate feeding. The VFAs concentrations 7–40.83 mM showed a linear relationship with biosensor voltage (18–67 mV) indicating that voltage < 18 mV was due to low organic matter. Likewise, VFAs concentration lower than 7.87 mM resulted in decreased biogas production rate (BPR) and required substrate feeding. In a continuous food waste AD, the biosensor guided feeding produced 558 mL/g VS with the highest biomethane (62.17%), comparing with 344 and 387 mL/g VS produced by conventional 3- and 7-days intervals feeding, respectively. The microbial community was also more stable under the new strategy, where Prevotella and Methanosarcina were ~6-fold and 1.5-fold higher than conventional groups. The developed portable biosensor (~$200) worked effectively during outdoor monitoring of a domestic biogas plant. The VFAs based MFC biosensors can enhance the biogas yield with minimum substrate feeding while maintaining a suitable microbial community.

Biogas potential assessment and characterization of Korean slaughterhouse waste for anaerobic digestion

The global slaughterhouse waste (SHW) generation is rapidly soaring due to expanding population and shifts in eating pattern. Anaerobic digestion (AD) enables a sustainable and cost-efficient treatment of SHW through biological conversion of the organics into biogas. To assess the feasibility and provide basics for planning, this study investigated the characteristics of the SHW in a year basis for a thorough set of parameters including the organic compositions and the CH4 production potential. The organic wastes could be categorized as the red (heart, lung and liver) and the white (large intestine) SHWs. The white SHW had a higher lipid content (average 22.4%, wet basis) as well as the solids, resulting in the CH4 potential of 684.8 mL/g VS which was approximately 1.4-fold that of the red SHW (483.6 mL/g VS). The low C/N ratio (7.1) of the red SHW due to the high protein content (14.5%, wet basis) could lead to ammonia inhibition if this waste is solely treated. Next-generation sequencing was analyzed to depict the microbial community and the importance of initial inoculum selection could be highlighted. The community structure greatly affected the lag phase of the biological process ranging 0.26–1.28 d for the red SHW and 0.35–3.08 d for the white SHW. The energy potential of SHW AD in Korea was estimated to be 10920 TOE/yr, which is as high as 14.5% of the domestic biogas energy production in 2019. Overall, the SHW can be considered as energy-intensive feedstock for AD, and co-digestion with other wastes such as food waste or waste sludge could be recommended.

Technical assessment of installed domestic biogas plants in Kavre, Nepal

Domestic biogas technology is a promising source of renewable energy for cooking in developing countries. It is popular in Nepal's rural and peri-urban areas and can be scaled-up to replace solid fuel cookstoves. This study focused on the technical assessment of installed biogas plants such as structural components, pipelines and valves, stove and burner, biogas production and utilization, and effluent disposal system in 303 homes in Kavre district, Nepal. Furthermore, it evaluated the feedstock material's physical and chemical parameters to ascertain their implications on biogas production. The plants' problems were mainly due to faulty components and lack of proper operation and maintenance. About 18% of plants were nonfunctional, out of which 9% of the plants were damaged due to the 2015 mega-earthquake. The highest number of damages was found in the mixture of the inlet structure. About 55% of mixtures were nonfunctional. Almost 77% of users used cow dung and toilet waste either individually or in combination with animal urine as feedstock materials in the digester. The Carbon: Nitrogen (C: N) ratio of feedstock materials ranged from 5:1–24:1, with only 4% of samples measuring C: N greater than 20:1. Similarly, pH (7.7) levels were on the higher side.

Analysis of Biohydrogen Production Potential from Organic Wastes Generated in Korea

Objectives : To mitigate greenhouse gas (GHG) emissions, our country is trying to replace fossil fuel to hydrogen (H2). H2 has higher energy yield (122 MJ/kg) than other energy sources (natural gas, coal, etc.), and is considered a clean fuel that produces only water upon combustion. The water electrolysis using renewable energy is one of the green-H2 producing methods, but its unstable characteristics depending on weather condition impede its practical application. Therefore, to establish green-H2 society, the use of waste and biomass is essential to fulfil the demand.Methods : In this study, we estimated the biohydrogen potential of organic solid wastes: food waste, livestock manure, and sewage sludge, which are the main feedstock of domestic biogas plant. For the H2 generation process, dark fermentation (DF) and steam biogas reforming (SBR) were considered.Results and Discussion : The potential amount of H2 through DF and SBR was 44,000 ton/y and 675,000 ton/y, respectively. The GHG reducing potential was estimated to be 5 million tons CO2-eq/year, but it can be lowered down to 2 million tons CO2-eq/year, considering the energy consumption during H2 generation process. Among the energy potential of produced H2, 7% and 60% is required for H2 production in DF and SBR, respectively.Conclusion The expected biohydrogen production was 718,000 ton/y which can account for about 14% of the domestic H2 production target in 2040 (526 million tons). The main source was livestock manure (86%), and minor fraction was from food waste (10%), and sewage sludge (4%). The GHG reducing potential was estimated to be 2 million tons CO2-eq/year, considering the energy consumption during H2 generation process.

Barriers in the progress of domestic biogas plants in rural Pakistan

ABSTRACT The energy crisis has pushed Pakistan way down the economic rankings. More than 70% the total population resides in rural regions. The energy crisis has crippled the lifestyle of the rural class (RC) in many aspects. For rural Pakistan, the energy scarcity, a hurdle in sustainable development, can be eliminated by biogas. Almost every rural family is associated with agriculture and owns livestock animals, therefore self-sufficient in biogas plant’s fuel. Fuel abundance and favourable climatic conditions make energy extraction from biomass facile and fruitful; still there are many reasons that RC is dumped in the energy crisis. In this paper, a survey is conducted in villages of Pakistan to discover the reasons due to which domestic biogas plants have not yet gained their due importance. Institutional, financial, awry planning and social barriers are highlighted at the grass root level in the development of biogas technology in rural Pakistan. In contrast, villages where biogas plants are present, the survey analysis revealed prosperity rendered through savings, reduction in diseases and workload. The paper concludes with an emphasis on the requirement of concrete and comprehensive policy that is capable to deal with the barriers in the route of biogas technology.

Willingness to pay for domestic biogas plants and distributing carbon revenues to influence their purchase: A case study in Nepal

Despite the potential benefits to human health and greenhouse gas mitigation, the uptake of biogas plants in Nepal and other developing countries has been less than optimal. We investigate the potential to stimulate the market for biogas plants through the distribution of environmental income generated from carbon credits. While previously identified in the literature, this has received limited experimental testing in the context of rural households in developing countries. We first use contingent valuation to assess willingness to pay for domestic biogas plants. Using Heckman selection models, we then examine how the provision of carbon revenue earnings influences household willingness to purchase in the absence of a subsidy. We find that households are willing to pay on average US $361.54 for a biogas digester, which is less than full market price of US $433.79, but higher than the current market price net of government subsidy. Household willingness to purchase is influenced by access to environmental income for those not initially in the market, but has no effect on those initially willing to purchase a biogas plant. Our findings suggest that the provision of environmental income has the potential to lead to more rapid and widespread adoption of biogas plants.

Assessment of Environmental Impact and Economic Viability of Domestic Biogas Plant Technology in Bangladesh

The study investigated the distinct environmental impacts and economic viability of domestic biogas technology in the countryside of Bangladesh. The study was carried out by a survey through personal interviews with biogas users. Seventy households were selected purposively and interviews were conducted through semi-structured questionnaires. The study mainly highlighted the potential reduction of greenhouse gas (GHG) emission and economic benefits of biogas utilization which were evaluated considering the substitution of traditional biomass fuels, by saving Liquefied Petroleum Gas (LPG) and cost of chemical fertilizer, and carbon trading. The economic benefits are addressed using some well-known economic indicators like Net Present Value (NPV), Payback Period (PBP), and Benefit-Cost Ratio (BCR). The results of the study revealed that a small-scale household anaerobic cow dung biogas digester not only exhibited the potential to cut carbon emissions on average by about 7.8 tons of CO2 equivalents yearly, but it also demonstrated the economic feasibility of doing so as the value of NPV and BCR was positive. This study recommends that the government approach, awareness program, and continuous and proper performing of the biogas technology are needed to intensify the multiples environmental benefits of the technology.

Small-scale biogas technology and clean cooking fuel: Assessing the potential and links with SDGs in low-income countries – A case study of Nepal

Small-scale biogas technology has been instrumental in providing clean cooking fuel in several low-income countries. This study investigates the role of domestic biogas technologies in meeting the Sustainable Development Goal (SDG) 7.1, i.e., the share of the population using modern cooking solutions, considering a case study in Nepal. The country has an over 60 years’ successful history in the development of household biogas technologies with more than 431,000 biogas plants installation in close co-operation with different stakeholders including government, international development agencies, and private companies. There has not been an appreciable technological development over several decades of biogas promotion in Nepal, nonetheless, there is a need for indigenous technologies that can cope with multi-feedstock and fluctuating ambient temperature. Household bio-digester is one of viable options for simultaneously producing clean energy source (i.e. biogas) and nutrient-rich digestate (i.e. bio-fertilizer). In Nepal, less than one percent of the total biogas potential has been harnessed despite the government’s support and financing schemes. The total potential of biogas production from livestock manure is estimated to be about 3043.58 million m3/year when the full potential will be utilized. The corresponding avoided emissions would be 4.35 million tonnes CO2eq/year. Clean cooking fuel from domestic biogas technology could help in achieving SDGs in low-income countries when plans and policies for promoting robust small-scale biogas technology are in place. This study also explores the complementarity and synergies of biogas development and their interlinkages with other SDGs.