One of the major problems in the development of renewable energy technologies is their high investment costs. However, technology development has an impact on technology prices, thus there is a mutual relationship between price and technology development. Government, buyer and owner of the technology are the three main players in renewable energy technology development. The development of these technologies is greatly affected by the behavior of the players.In this paper, pricing of anaerobic digester as a renewable energy technology is modeled using system dynamics. A system dynamic model is proposed to model the relationship between the interests of different players, price and technology.

The major purpose of this study was to examine the advantages and implications of BIOGAS technology in the agriculture sector. BIOGAS is one of many biomass energy sources, which include anything that was once alive and that can generate energy (except for fossil fuels, which are not renewable). To talk of BIOGAS is to talk of agriculture, since BIOGAS generation starts with agricultural waste produce, such as cow dung, husk, straw etc. and ends with agricultural produce, use of slurry on crops. Slurry is one of the most environmentally sound organic fertilizers in use today. The information collected in this study by reviewing literatures. Renewable energy sources have a large potential to contribute to the sustainable development of specific territories by providing them with a wide variety of socioeconomic benefits, including personal/household impacts, health impacts, social, economic and environmental impacts. BIOGAS as an adaptive and cost-effective energy system, integrate livestock into the farming system.

Due to the increasing population growth and energy requirement, the interest in renewable energy sources has increased in the recent years. BIOGAS is one of the sustainable energy resources in the world. In the cattle, ovine, and poultry farming, a large amount of fertilizer is produced in Afghanistan. These wastes are a big problem for businesses, and their evaluation is of great importance. One of the ways to utilize the wastes is the BIOGAS production. In this work, the annual BIOGAS and the total annual heat value potential of Afghanistan are determined depending on the number of animals. As a result, the Afghanistan's BIOGAS potential between 2010 and 2017 is between 1172355870 m 3 /y and 1282692614 m 3 /y. According to the results obtained, the total annual heat value potential is between 29117122340 MJ/y and 26612478246 MJ/y. As a result, the widespread use of BIOGAS in Afghanistan is of great importance in terms of both the waste disposal and the energy production.

There is a great need to implement low-cost and user-friendly methods for further propagation of BIOGAS technology in India. Environment unfriendly disposal of floral waste causes serious environmental pollution. Literature shows a limited research work regarding the anaerobic digestion of floral waste for BIOGAS generation. The present experimental work aims to propagate floral waste as a sustainable source of BIOGAS energy in India. Using different techniques like novel alkaline pretreatment, solar heating of the digester and co-digestion with food waste give enhanced BIOGAS production from floral waste. A novel alkaline pretreatment of the floral waste using sodium carbonate and sodium bicarbonate gives an improvement in BIOGAS output by 106%, with a saving in the cost of chemical pretreatment up to 96%, compared to traditional sodium hydroxide pretreatment. Also, solar heating of the digester increases the BIOGAS output by 122% as compared to digesters in ambient conditions. Co-digestion of the floral waste with food waste also improves BIOGAS output by 32. 6%. Raw BIOGAS from floral waste contains over 57% methane, which is higher than the previous studies. Large-scale application of the techniques can benefit the society.

Background: Following an extensive examination of various biofiltration packing materials within a typical bioreactor (a biofilter) is aiming to remove hydrogen sulfide (H2S) in the raw BIOGAS. Methods: Both biochar (pre- and post-pyrolysis at 400, 500, and 600 °C) and cellular concrete (CLC) waste, representing organic and inorganic packing materials, respectively, displayed remarkable removal efficiency (RE) performance under dynamic conditions. Nevertheless, the physical and chemical properties of these packing materials play a crucial role in absorbing and trapping H2S for further filtration from the raw BIOGAS. Key evaluations encompass chemical compositions, porosity, and specific surface area, aligning with contemporary research methodologies (e.g., XRF, Walkley-black, Kjeldahl, BET, T-plot), as analyzed in this study. Results: Subsequently, the modification of these physicochemical properties aimed to demonstrate continued interactions of iron (III) oxide (Fe2O3) with H2S for chemical modification of CLC waste, and enhance the specific surface area of biochar from 12, 22, and 24 m2/g to 235, 433, 475 m2/g, and for porosity from 0.01, 0.42, and 0.025 cm3/g to 0.096, 4, 0.24 cm3/g, respectively, for physical modification of biochar samples after pyrolysis at 400, 500, and 600 °C. Conclusion: In the end, improving the possibility of getting better RE from a laboratory-scale biofilter is possible by modification of the most effective physical (adding KOH to biochar and increasing porosity by 9 times, specific surface area by 19 times) and chemical (adding Fe2O3 to CLC waste) properties of the environment-friendly packing materials.

BIOGAS technology is the answer to our environmental and economic needs is extremely convenient. Factors such as carbon to nitrogen ratio of raw materials, d, our terms and PH geography place in quality and quantity of products involved. The study demonstrated that the BIOGAS and the feeding system is usually three discontinuous, is a semi-continuous and continuous. The amount of methane gas using mathematical at different temperatures and conditions geography where sludge has been paid. The results of the highest gas production at 40-10 days and temperatures of 35-15 degrees and BIOGAS coefficient between zero and a 60 percent to various local conditions are obtained.

Annually about 85, 000 tons of raw hides and skins are estimated to be processed for leather production in Bangladesh. Tannery generates huge amount of solid and liquid wastes. Anaerobic digestion (AD) is a potential treatment to stabilize waste and produce BIOGAS for renewable energy. The aim of this study was to investigate the potential of AD of tannery solid waste (TSW) generated from the pretanning operation and to compare the effect of cow dung as the substrate to TSW. For the reaction with TSW by mixing with different substrates, BIOGAS production was observed starting on 4th day with a steady increase. The cumulative gas production from each of the test reactors operating at the various organic loading of tannery solid waste, domestic sewage, and cow dung were different. This study shows an optimal AD process of TSW by mixing with different substrates for the obtained optimum C/N ratio and also for the high volatile solids (VS). The COD removal rates for the series of 5 reactors (R1, R2, R3, R4 and R5) were 48. 75, 50. 84, 46. 07, 45. 94 and 47. 78% respectively. Maximum COD removal was achieved from reactor R2 where maximum gas was also produced.