Source Of Biogas Research Articles

Environmental methane emissions from seagrass wrack and evaluation of salinity effect on microbial community composition

Methane generation from seagrass contributes to green-house gases emissions but can also be a potential controlled biogas source. Understanding the natural fluctuations of emissions and the biotic and abiotic factors underlying such variations is essential. In this work, CH4 emission from beach-cast seagrass from the High-Adriatic coast was analysed. Biochemical methane potential (BMP) tests were used to evaluate CH4 generation at different temperatures (30 °C and 35 °C) and salinity levels (from 0‰ to 35‰), consistent with the typical observed environmental conditions. The changes in the microorganism community composition were investigated by means of amplicon metagenomics sequencing. The results underlined a specific CH4 emission in the range of 0.90–1.37 NmL CH4/g Volatile Solids (VS) d at 35 °C and 0.36–0.50 NmL CH4/g VS d at 30 °C. The most intense methane generation was observed at intermediate salinity levels of 18‰ at 35 °C and 9‰ at 30 °C. The total seasonal emission from the investigated beach-cast seagrass was estimated as 0.1399 mmol CH4/m2g. The microbial community analysis highlighted that Rhodobacteraceae was the most abundant family, coherently with its abundance in the marine environment. Low salinity (0–9‰) samples showed a prevalence of carbohydrate–degrading Ruminococcaceae, while the carbohydrate-fermenting Petrotogaceae were more abundant in high salinity (18–35‰) samples. The total lack of an important functional class was not noticed in any salinity level, except for sulphate-reducing bacteria, which were virtually absent when salinity was 0‰. The present study allows a better understanding of the environmental conditions resulting in a higher methanogenic potential and an enhanced comprehension of the bacterial communities associated to this process. The obtained information can be of help for designing efficient systems for producing methane from seagrass wrack, as well as for selecting the most appropriate managing route among the currently available technologies (such as on-site environmental preservation, composting, anaerobic digestion).

Siloxane adsorption by porous silica synthesized from residual sand of wastewater treatment

Wastewater from municipal sewage may be an interesting source of biogas, in which case siloxanes are commonly present above the spec limit to be used in power engines. On the other hand, residual sand from Wastewater Treatment (WWT) Plants is also rich in inorganic matter, which can be a suitable feedstock for the synthesis of porous inorganic adsorbents. This work describes the synthesis of an alternative adsorbent for siloxane adsorption using residual sand from a WWT plant. The ultimate goal was to find a substitute for commercial activated carbons or silicas currently employed in siloxane removal from biogas. The residual sand was subject to thermal and acid treatment, which successfully increased its silicon content while developing adequate internal porosity. The textural characteristics and the chemical composition of the new adsorbent were similar to those found in commercial silica gels. Liquid phase adsorption isotherms and uptake rate curves were measured for siloxanes Octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5). The siloxane uptakes and adsorption kinetics were comparable and even superior to those found in commercial silicas, especially at low adsorbate concentrations. These results demonstrate the potential of residual sand from WWT as a suitable raw material to produce a good adsorbent for the removal of cyclic siloxanes from biogas.

Biomethane production by adsorption technology: new cycle development, adsorbent selection and process optimization

Gas separation by adsorption processes such as pressure swing adsorption (PSA) presents an attractive alternative for upgrading biogas to biomethane. A new vacuum pressure swing adsorption (VPSA) cycle is proposed for a unit designed to purify pre-cleaned biogas (40% CO2 and 60% CH4) in industrial conditions (feed flow rate more than 500 Nm3/h and large-volume equipment). The process simulations performed to optimize the VPSA unit consider the kinetic separation of the feed components by using an appropriate carbon molecular sieve (CMS) adsorbent having a high kinetic separation selectivity for CO2 with respect to CH4. The designed VPSA unit is composed of five columns that perform three equalization steps. Minimizing methane losses during the regeneration steps necessitates injecting part of the off-gas rich in CO2 at the bottom of the column during the production step to push the CH4 forward. The produced biomethane meets the specification (97% CH4) of grid injection purity. The developed cycle allows a CH4 recovery of 92% to be obtained with a specific energy consumption of 0.35 kWh/Nm3, thus meeting the initial requirements for industrial exploitation of VPSA technology for biomethane purification from biogas sources.

A simulation study on a port-injection SI engine fueled with hydroxy-enriched biogas

ABSTRACT In addition to other renewable energy sources being used to minimize the environmental pollution and climate change as well as to satisfy the ever-increasing demands of the society on the energy, biogas is considered abundant resources for energy production. The strategies of using biogas source for internal combustion engines may be a good and potential solution for saving fossil fuel and reducing pollution emission. In this current study, hydroxy (HHO) -enriched biogas under two pathways such as dual injection and blend injection was used to fuel an SI engine aiming to assess the performance (via in-cylinder pressure and indicated cycle work) and emission characteristics (CO and NOx emissions) when the input parameters including HHO/biogas ratios, the position of butterfly valve in the intake manifold, angle of HHO injection were varied. As a result, the dual injection strategy of HHO-enriched biogas produced an advantageous distribution of H2 and CH4 in combustion chamber, which improved combustion efficiency and reduced pollutant emissions. With a fixed HHO injection duration of 2.7 ms, the dual injection led to an increase in HHO concentration at all engine loads, which improved complete combustion in critical operating conditions. Increase of HHO content led to a decrease of optimal advance ignition angle and reduced the range of its variation with engine speed. In closing, HHO addition into biogas was found to improve the engine performance, to reduce CO emission, although it also increases NOx concentration. Biogas enriched by 20% HHO was considered as the best compromise between engine performance and pollution emissions with indicated engine cycle work of 204 J/cyc, CO emission of 0.74%, and NOx emission of 1192 ppm. Moreover, the ignition maps for biogas and HHO were built to point out the optimal range of advance ignition timing for the application purpose to real experiments in the future.

Technical feasibility of reforming anaerobic digestion and landfill biogas streams into bio-hydrogen

Hydrogen can be produced through different pathways, i.e., natural gas reforming, gasification of coal, and electrolysis of water. A more sustainable pathway is through bio-H2, which can be produced by bio-photolysis of water and photo-fermentation and dark fermentation of organic matters (OM). However, these routes are still limited by their specific energy requirement, process slowness, and microorganism sensitivity. These limitations can be mitigated by producing bio-H2 via steam reforming of biogas sources such as landfill or anaerobic digester. In this study, the influence of the methane concentration in the biogas stream on reforming metrics was investigated. Two levels of modeling were pursued here: equilibrium and high fidelity numerical simulations. The former considers several reaction constants, elemental mass conservation, and energy balance. The latter model is based on the reactive Navier-Stokes of non-isothermal and multiple species flow in a cylindrical reactor. Process metrics such as species concentrations and conversion percentages as well as thermal process efficiencies were delineated and evaluated. Results showed that methane concentration has a pronounced influence on the resulting hydrogen concentration and the overall reforming efficiency. The anaerobic CH4 source resulted in a mole fraction of near 0.3 for H2 and a reforming efficiency of 36%. These values are much lower than those evaluated for natural gas (mole fraction of 0.5 for H2 and reforming efficiency of 75%). Although this work illustrates the technical feasibility of biogas reforming, it highlights the low attained process efficiency that can be improved to achieve sustainable bio-H2 production.

Utilization of renewable sources of biogas for small-scale production of liquid fuels

Low energy density in agricultural or biotechnological raw materials dictates the need for their local processing. Small-scale agricultural products or waste processing plants can`t profitably use technologies common in large-scale petrochemistry, including the complex and expensive process of steam reforming of biogas into syngas for its subsequent conversion to liquid fuel. The work suggests using small-scale sources of inexpensive and easily obtained biogas and other renewable hydrocarbon gases for the production of liquid biofuel by their air conversion in recently developed matrix reformers into low-cost nitrogen-rich syngas, followed by Fischer-Tropsch synthesis in a cascade of sequential reactors. Autothermal matrix reformers are very compact, simple in design, have several times more specific volume capacity than traditional technologies, and allow processing biogas with a high concentration of CO2. The advantages of low-cost conversion of biogas to liquid fuel based on nitrogen- enriched syngas with subsequent Fischer-Tropsch synthesis are discussed.

Yields, Calorific Value and Chemical Properties of Cup Plant Silphium perfoliatum L. Biomass, Depending on the Method of Establishing the Plantation

Silphium perfoliatum L. (Silphium) is one of the most promising perennial herbaceous plants, mainly due to its high biomass yield and multiple uses. It can be grown as a fodder, ornamentally, for energy (mainly as a biogas source), and as a honey crop (source of nectar and pollen for pollinators). Despite the considerable qualities of this crop, the Silphium cultivation area in Europe is small. The main limiting factors are the significant costs of plantation establishment and the lack of biomass yield in the first year of cultivation. Considering these aspects, research was undertaken at the Agricultural Experimental Station Lipnik of West Pomeranian University of Technology Szczecin, to assess two methods of establishing a plantation: generative, by sowing seeds (seeds); and vegetative, by transplanting seedlings grown from seeds (planting), on the yield and quality of Silphium biomass attended for combustion and its heating value and chemical composition. In 2016–2019, annual aboveground biomass was harvested after the end of vegetation to obtain the raw material for combustion. The collected dry mass yield (DMY) of Silphium significantly differed between the years and methods of establishing the plantation. The biomass yields increased in the first two years of full vegetation from 9.3 to 18.1 Mg∙ha−1·yr−1, and then decreased in the third year of vegetation to ca. 13 Mg∙ha−1·yr−1 because of drought. Significantly higher DMY was obtained by sowing seeds (ca. 13.9 Mg∙ha−1·yr−1) compared to the planting method (ca. 13.0 Mg∙ha−1·yr−1), due to the higher plant density obtained after the sowing method compared to the planting method. The calorific value in the third year was the highest and amounted to ca. 17.8 MJ·kg−1 DM. The paper also presents changes in soil chemical properties before and after four years of Silphium cultivation.

English

Injera will continue to be the staple food for Ethiopians and Eritreans and some parts in east Africa in years to come. In order to efficiently bake Injera using various types of stoves, research and development work for Injera baking have been conducted so far and is critical. The use of energy sources is dominantly biomass is used for Injera baking followed by electricity yet. Electricity is mainly used in urban dwellers of the country which is limited one. Alternative energy sources such as solar thermal and biogas can be used for baking Injera alternatively. There are different types of Injera baking stoves design in Ethiopia using biomass energy such as open fire three stone stove, Mirt stove (includes improved one with high chimney, stand types), Burayou Injera baking stove Sodo, Awuramba, Tehesh indicating developmental patterns of stove based on the aim to reduce specific fuel consumption as well as efficiency by reducing energy losses during baking. Thus, it is determined that the average specific fuel consumption of three stone open fire was 929 g/kg of Injera, Mirt stove is 535g/kg of Injera, Gonziye is 617 g/kg of Injera, Awuramba is 573 g/kg of Injera while Sodo is 900 g/kg of Injera. The other Injera baking stoves were developed for baking Injera using solar thermal energy and biogas sources are designed to attain the average required surface temperature of Injera baking pan or Mitad. It is found that the average surface temperature of the concentric type solar thermal Injera baking stove is 148 oC, parabolic type solar Injera baking stove is 200 oC, electric stove is 225 oC using 3.75 KW electricity, WASS electrical is 220 oC consuming 1.4 KW electricity and biogas 210 oC. Further investigation needed to continue the developmental patterns of Injera baking system by improving the efficiency of the stove by reducing energy losses there has needed that the baking pan or Mitad to be improved.

Energy Planning and Sustainable Biogas Production Prospect Within Residential Quarters in Developing Countries

The prospects of biogas as a major energy option to alleviate the energy needs in Africa is huge based on its teeming population. However, the main source of biogas i.e. human excretal is being neglected, thereby loosing resource worth 500 MW of electricity. This research is geared towards estimating the accruable biogas that can be harnessed in a typical student hostel in a developing country. The data was collected at the main chamber of the hostel. The estimation of the optimized state of methane, hydrogen sulphide and carbon dioxide is given as 12%, 0.94% and 4.42% respectively. It was also affirmed that the algae growth on the walls of the sewage line is responsible for the low carbon dioxide values. Also, it was reported that the production of hydrogen sulphide gas is predictable, as it is not directly related to the concentration of microorganism in the sewage chamber. This research gives an eye-opener on biogas wastage in developing countries.

Green biomass to biogas – A study on anaerobic monodigestion of para grass

Recently, biogas production through anaerobic digestion technology has advanced massively. At the moment, caused by high energy demand and environmental concerns as the world’s population increases, the drive for anaerobic digestion processes is achievement drive within research and the industry for sustainable energy generation. The study evaluated biogas production from anaerobic mono-digestion of para grass in laboratory scale studies. In addition, improvement of the biogas yield from the grass via chemical pretreatment and leaching bed reactors was studied. Methane content of biogas was 54.36 % by mono- substrate. The results revealed that para grass can be treated anaerobically and are a good source of biogas.

Comparative evaluation of the effect of pore size and temperature on gas transport in nano-structured ceramic membranes for biogas upgrading

As a result of rising economies and environmental constraints, the demand for clean and renewable sources of energy is fast increasing. Biogas is a renewable form of energy that fits all expectations in terms of delivery, cost, and greenhouse emissions reduction. Biogas utilization is advantageous because it is a means of creating wealth from daily human, agricultural, household and municipal waste that could otherwise be polluting the environment as waste is deposited on a daily basis which are potential biogas sources; it is not dependent on weather conditions as other renewable forms (solar and wind). Biogas can also be compressed, stored and transported, and therefore easily responds to changes in demand. This paper entails the use of nano-structured membranes to upgrade biogas (which contains primarily methane and carbon dioxide). The benefits of membranes include their compact structure and ease of usage with low maintenance, their low running costs and minimal loss of the upgraded gas. 15nm, 200nm and 6000nm membranes were used to ascertain the flux of the model biogas mixture passing through it under various operating conditions. In each case, the exit flowrate of methane was higher than that of carbon dioxide and this is attributed to the pore sizes of the membrane and its ability to filter the heavier gases. The results show that the molecular weight of the gases also play a role in their permeation rate as it follows the Knudsen regime.

Synthesis of optimal biogas production system from multiple sources of wastewater and organic waste

Biogas is one of the products that can be produced from wastewater or organic waste. Given the input streams for biogas digester can come from multiple sources rich in organic compound, optimization can be performed to maximise the production. In an industrial park with several types of industry, wastewaters and/or organic wastes from the industries or surrounding area can be used as feedstock for biogas production. Compared to conventional industrial park, Eco-Industrial Park (EIP) could be the appropriate platform for implementation as it advocates for industrial symbiosis through materials exchange and minimisation of waste, which are also in-line with the circular economy concept. In this study, a superstructure applicable for an EIP, which consists of multiple biogas sources, biogas digester, biogas upgrading, and biogas demands are developed. The model considers parameters which can affect biogas production quality and quantity such as Chemical Oxygen Demand (COD), Carbon/Nitrogen ratio (C/N ratio), and temperature. It also considers percentage of methane lost, removal efficiency of Carbon Dioxide (CO2), electricity cost, capital cost of the selected biogas digesters as well as the cleaning and upgrading units. The main objective of the mathematical model is to maximise the profit generation from biogas generation for the EIP centralized biogas production plant. The model is solved by using General Algebraic Modelling System (GAMS) software. Case study conducted shows that anaerobic closed lagoon is selected as digester for the industrial wastewaters, while water scrubber is suggested as the biogas upgrading technology. A yearly profit is estimated at USD13,700,000, which is generated from selling of 279nm3 of purified biogas. This may suggest that generating biogas from several sources of industrial wastewater and organic waste could be potentially feasible, thus reducing unnecessary pollutant while capturing the carbon source as an additional revenue stream.

Processing human biogas using drying agent

Biogas production in cow dung supersedes other bio-waste product. Human waste is one of the lowest biogas sources. More so, the nature of the human excretal deposition matters. There are higher biogas productions in pit latrines than in water closet (WC) system. However, it is known that WC users are the majority in modern building design. The main disadvantage of the WC system ingenerating biogas is that the solid excretal is broken into pieces by water dissolution and collision with the sewage pipe. The chemistry of the event is that the little biogas produced has high percentage of moist. In this research we deployed drying agents to process the biogas from WC system.

How to find high-quality petroleum source rocks in saline lacustrine basins: A case study from the Cenozoic Qaidam Basin, NW China

Despite having made significant contributions to global hydrocarbon occurrences, source rocks in saline lacustrine basins show great mineralogical and organic geochemical heterogeneity and the controlling mechanism is weakly studied. Here, we use the Cenozoic Qaidam Basin as an example to compare the organic and inorganic parameters of fine-grained sediments in different lacustrine facies and to figure out the characterization and distribution of effective petroleum source rocks in saline lacustrine systems. Organic-inorganic database of six selected boreholes show that in the bench-margin (high-gradient) lacustrine system, fine-grained sediments in sublittoral brackish-mesosaline zones containing low chlorides (<2000 ppm) and high carbonates (25–50%) show low total organic carbon (TOC) contents (0.4–1.0%) and high chloroform extracts (0.05–0.2%); centripetally sediments in penesaline profundal zones averagely have higher chlorides (2000–15000 ppm), lower carbonates (15–35%), higher TOC contents (0.6–1.2%), and higher extracts (0.05–0.3%). These two facies can both develop valid petroleum source rocks. In the ramp-margin (low-gradient) lacustrine system, dark fine-grained sediments in penesaline centers with low carbonate (15–25%) and high chloride contents (2000–15000 ppm) show high TOC contents (0.8–2.0%) but extremely low hydrogen indexes (<100 mg HC/g TOC) (little extracts), only developing as valid gas/or biogas source rocks. Supersaline fine-grained sediments in both lacustrine systems develop invalid source rocks. Lateral superimposition maps show that fine-grained sediments with high hydrocarbon generation potential generally contain averagely 25–50% carbonates. Therefore, brackish-penesaline water salinity and bench-type basement are two necessary conditions to develop high-quality petroleum source rocks in saline lacustrine systems and average carbonate content can be a general good mineralogical indicator.

Evaluating the biochemical potential for Irbid’s food waste as a source for energy

ABSTRACT Solid waste generated from the city of Irbid is all directed to a local unlined landfill with no gas collection system. More than half of the waste stream is made of food waste which turns the landfill to a concentrated point source of greenhouse gases. To assess the impact that the landfill has at the moment on global warming and to evaluate the future value of the city’s waste as a source of biogas, 20 trucks of municipal solid waste were sampled. In addition, food waste samples from Irbid were collected from five different sources for 12 weeks to quantify their generation rates and to measure their components and chemical composition. Irbid’s solid waste was found to have a distinctively high biodegradable content 68%, which is typical of developing countries’ solid waste. Physical assessment showed that 38%, 6%, 33% and 23% of the food waste was rice, meat, fruits and vegetables, and bread, respectively. Measured methane yields for the volatile solids (VS) in rice, meat, fruits and vegetables, and bread were 362, 499, 352 and 375 mL/g VS, respectively. A representative food waste sample was created to test the actual methane yield and compare it to calculated one. Actual methane yield (414 mL/g VS) was greater than the calculated value (370 mL/g VS) based on food type proportions and their specific methane yield. To assess the anaerobic biodegradability of food waste, a stoichiometric calculation of the methane production was made based on the elemental analysis of all food waste elements. Food waste was found to have the chemical formula C7H16O5N and calculated methane potential of 447 mL/g VS; indicating 85% anaerobic biodegradability of food waste, which makes Irbid’s waste perceived as a valuable source of energy.

Economic and Technological Analysis of Commercial LNG Production in the EU

There is a global need to increase the production of alternative sources of energy due to many issues related to conventional sources, such as environmental degradation or energy security. In this paper, decentralized liquefied natural gas production is analyzed. Liquefied natural gas, according to the analysis, can be considered a viable alternative even for decentralized applications Design and economic analysis of a small-scale biogas LNG plan together with the necessary technology and economic evaluation are presented in the paper. The results show that a project of the proposed size (EUR 3 million) offers a relatively good profitability level. Specifically, the net present value of the project is mostly positive (around EUR 0.1 million up to EUR 0.8 million). Therefore, based on the research, small LNG plants operating across the continent can be recommended for the processing of local sources of biogas.

Hybrid anaerobic-aerobic biological treatment for real textile wastewater

In this study, working of hybrid anaerobic-aerobic biological treatment technology for real textile wastewater was investigated on the basis of system evaluation and optimization in two phases. In Phase I, system was optimized at laboratory scale on synthetic textile wastewater and later real textile wastewater was treated in Phase II. The study was conducted for 242 days in which industrial discharge coming from textile mill was collected and subjected to laboratory scale hybrid treatment. Activated sludge used in the process was obtained from full scale membrane bioreactor (MBR) plant and adapted to the synthetic and real textile wastewater using anaerobic process. Individual application of anaerobic treatment was found to be insufficient for the removal of COD, TKN and dyes. The proposed combine hybrid anaerobic-aerobic system was found to be effective in reporting removal efficiencies of 99.5% COD, 99.3% TKN, and 78.4% dyes. The anaerobic SBR added value to the hybrid system as it played a key role in improving treatment efficiency in addition to the production of sustainable energy source of biogas. Study shows that aerobic treatment is required to increase the treatment level by providing the final polishing to anaerobically treated effluent in order to reclaim water. The optimum HRT for hybrid anaerobic-aerobic system in treating real textile wastewater was found to be 54 h for maximum COD removal. The implication of this work is the industrial application of hybrid anaerobic-aerobic system for reuse of water in agricultural and industrial sectors.

Renewable based biogas upgrading

A facility for the upgrading of biogas into biomethane using renewable hydrogen has been analyzed. The biogas source is the organic matter within municipal waste. For biogas to be fed to the grid, CO2 is to be transformed. Methanation of the CO2 with renewable hydrogen is carried out. Solar and/or wind energy are the power sources for the facility. The design problem is formulated as a multiperiod optimization one for the selection of the renewable technology or combination of technologies for the production of hydrogen. Two cases of study are evaluated, regions where either wind or solar availability are high, UK and Spain respectively, and two modes of operation, continuum upgrading of the biogas or variable. Continuum upgrading is more expensive due to the large contribution of the renewable hydrogen production into the cost. Variable upgrading rate benefits from biogas storage and makes the most of the available wind and solar energy. While in the UK wind is enough to upgrade the biogas, in Spain Solar is preferred, but the large area required results in the need to use wind turbines in case continuum upgrading is required. The framework is general to analyze the type of facility that operates best in any country.

The use of green macroalgae (Ulva lactuca and Codium tomentosum) that have a high methane potential, as a source of biogas in Senegal

Anaerobic digestion is a biochemical process that occurs naturally in the absence of oxygen. It is used commonly in developing countries to produce both energy and biofertilizers.Objective: The purpose of this work was to study the anaerobic digestion of green macroalgae (Ulva lactuca and Codium tomentosum), which cause severe environmental problems in Dakar-Senegal, and elsewherealong Africa's Atlantic coast.Methodology and Results: These green macroalgae were characterized in terms of physicochemical properties and biochemical methane potential (BMP). Their characteristics were compared to those of other locally available feedstock, such as cow manure and Jatropha curcas cake. The results showed that volatile solids of macroalgae were about 500 g VS/kg and twice that of cow manure. Furthermore, the methane potential ofmacroalgae was twice (216.4 L CH4/kg VS) that of cow manure (100.3 L CH4/kg VS). The green macroalgae achieved a heating value potential of 2151 kWh/t VS. The methane potential of Jatropha cake as a substrate foranaerobic digestion was intermediate (133.6 L CH4/kg VS) but contained a large quantity of lignin (34%), a slowly biodegradable organic substance.Conclusions and application of findings: This study results showed that green macroalgae could be used as a substrate for the production of renewable energy the biogas in Senegal.Keywords: Biogas, renewable energy, biochemical methane potential, macroalgae, Jatropha curcas.

Spatial-economic optimisation of biomethane injection into natural gas grid: The case at southern Malaysia

Energy is widely used in industry for heating and cooling, with natural gas (NG) being the largest primary energy source in Malaysia, closely followed by coal. Renewable energy, such as biogas upgrading to biomethane, could cut the use of fossil fuels by supplementing NG usage due to their similar physicochemical and thermochemical characteristics. Biogas production plants in Malaysia are more commonly seen in waste-to-energy scenarios, with the technology anaerobic digestion, and their deployment is supported via feed-in tariffs (FiT) for power generation. Other potential applications such as the conversion of biogas into biomethane, injection into the natural gas grid or transportation through a virtual pipeline may still need further technical development. This paper presents spatial techno economic optimisation modelling using BeWhere to determine decentralised biomethane production plants using feedstock from multiple sources of biogas, including palm oil mill effluent (POME), food waste, cattle manure and chicken manure. This model considered potential configurations and sizes of the biomethane plants, the transportation of biomethane using a virtual pipeline (at 250 psig) and demand in one of the states in Malaysia, namely Johor. It was found that two to four biomethane plants with capacities ranging between 125 and 700 m3/h were located in densely populated areas or heavier industrial consumers when the carbon tax was implemented at 167.71 EUR/tCO2 (800 MYR/tCO2). Sensitivity analysis suggested that biomethane production increases with the increasing country renewable energy share target to beyond 2080 MW. It is recommended that specific policy regulations and Feed-in Tariff (FiT) mechanisms are used to expand the biomethane market share in the country.