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A long-term feasibility analysis of a 100 ton per day mechanical biological treatment (MBT) plant for municipal solid waste (MSW) valorization and material and energy recovery was carried out. It involves the material recovery and segregation stage (MRSS), organic extraction (pulping), thermophilic anaerobic digestion (AD), composting, effluent treatment plant (ETP), and biogas genset stages producing: 11.90% recyclables, 33% refused derived fuel (RDF), 5% compost of total waste received, 70 m3/day recyclable water and 0.435 MWh/day electricity. The biogas and methane yield were 0.535 and 0.350 m3/kg VS added (avg.), respectively, with 40% VS removal (avg total solids (TS) 10%). Less than 3% (inert) of total waste received was subjected to landfill disposal. The MBT plant's revenue generation is 995 US$ per day/148 tons ($ 6.72/ton) waste processed. The gross OPEX is 24 US$/ton making the net OPEX of 17 US$/ton (minus revenue), which could be considered as the excellent OPEX for MSW based MBT plants as per global benchmarks. Further, local usage of RDF can significantly reduce the OPEX to 14 US$/ton, as almost 16% of the OPEX goes towards RDF disposal to cement companies located at a distance of 200–500 km from the MBT plant site. As per LCA study, the total GHG emissions have been calculated to be −25.68 tons CO 2 eq./100 tons MSW. The negative emissions result from the export of electricity, compost, and RDF as well as recycling of paper and plastic products. Our study presents a cutting-edge scenario of all-inclusive recycling, recovery, and reuse loop of MSW direly required for accomplishing a circular economy. [Display omitted] • Long term performance of first successful 100 tons/d MBT plant in India was studied. • 12% recyclable, 33% RDF, 0.435 MWh/d power, 5% compost, 70 m3/d water were recovered. • Biogas and methane yield were 0.535 and 0.350 m3/kgVS added (65%CH 4), 40%VS removal. • MBT plant has OPEX of US$ 24/ton and revenue of $6.72/ton; net OPEX of US$ 17/ton. • LCA study revealed the negative GHG emission of −41.45 tons CO 2 eq./100 tons MSW. [ABSTRACT FROM AUTHOR]

Currently, energy consumption for cooking in rural households of India is mostly based on fuelwood used in traditional stoves. This paper presents results of a study carried out in a forest fringe area of India on cooking energy use. The concept of calculating levelized cost as cost per unit of useful energy is applied on source-device combinations of cooking and validated in Bargaon Community Development Block of Sundergarh District in Odisha, India. About 92 % of the households in the study area use fuelwood as the only energy source for cooking; the total use of fuelwood for only cooking, in the Block is nearly 1.8 times the total sustainable wood supply showing an urgent need for promoting alternative cooking energy options. This paper also presents an assessment of different cooking options in terms of cost per unit of useful cooking energy. LPG, biogas and gasifier stoves are found to be far too expensive for the local people. Briquette-fired improved stoves appear to be a promising cooking energy option in the study area. Government support and intervention are recommended for promoting this option. [ABSTRACT FROM AUTHOR]

The coir industry in India's southern coastal regions, especially in the state of Kerala, is becoming increasingly concerned about the environmental impact of the accumulation and incremental increase of coir pith each year. The objective of this study was to assess the effect of pretreatment on the anaerobic digestion of coir pith. The characterization study of coir pith shows high organic content, which can be anaerobically digested to produce biogas. But, the high lignin content (30.91%) makes the process slow. To overcome this, a biological pretreatment method was tried using two microbial cultures belonging to fungal genera known to be lignin decomposers, viz., Trichoderma and Pleurotus. By using Trichoderma, lignin content was reduced by 3.7%, and the maximum gas production was obtained in a shorter time (19 days) in comparison with the sample without any pretreatment (24 days). When Pleurotus was used for lignin degradation, the lignin content was reduced by 6.78%, and the maximum gas production was obtained in a much shorter time period (14 days) in comparison with the former two methods. The gas produced comprises 74 ppm of methane, which has fuel value. The sludge after digestion was tested, which indicated a marginal increase in NPK value and hence can be used as fertilizer. The results of the study appear to be quite promising in the transition towards green energy by providing scope for the process of biomethanation, with the conclusion that further research can transform coir pith into a good renewable energy resource. [ABSTRACT FROM AUTHOR]

The application of compressed biogas (CBG) in day-to-day livelihood has garnered significant attention in modern day era. It is considered as a potential solution to curb the increasing energy demand and other environmental concerns. The process involves anaerobic digestion (AD) (hydrolysis, acidogenesis, acetogenesis and methanogenesis) of organic substrate under an optimum operating condition (pH, temperature, etc.) via anaerobic microorganisms. This paper aims to describe some major facts about different technological options related to pre-treatment, AD, cleaning and up-gradation system. It also highlights the practical challenges related to high investment cost, inadequate infrastructure, clearance and approval issues, poor feedstock supply chain management etc. in adaption of CBG plants in India. The review examines the significance of both dry and wet continuous digester systems, which includes its advantages and challenges, considering factors, such as feedstock characteristics, process stability, and operational efficiency. It was also found that the type of feedstock and its availability in existing market plays a vital role in smooth functioning of CBG plants. Therefore, the study presents a comprehensive review discussing potential feedstock readily available for CBG plants in Indian market. It was concluded that the usage of agricultural waste (such as Napier grass) has higher CBG potential compared to other feedstock. At the same time, the study presents a broader aspect to policy makers and governing authorities to reframe the existing structure for financial assistantship, regulatory laws, subsidiary schemes etc. for CBG plant owners. It also gives an opportunity to technocrats, industrialist and investors to come-up with an indigenous technology with in-house manufacturing units to promote CBG production in India. [Display omitted] • India has 46 compressed biogas plants with an overall capacity of 272 tonnes/day. • Elaborated the significance of both dry and wet continuous digester systems. • Setting-up a compressed biogas plants requires high investment and operational cost. • Potential market for bio-fuels and bio-fertilizer needs to be explored in India. • Existing financial assistantship and subsidiary schemes need transformation. [ABSTRACT FROM AUTHOR]

The maintenance of people's lifestyle against global climate change, exhaustion of groundwater, depletion of minerals, and water scarcity has instigated the recycling and reuse of water from unlikely sources. This situation has motivated researchers to develop effective technologies for treating wastewater, enabling its reuse. Water security has been ensured in myriad, highly populated regions through large-scale centralized treatment facilities. The development and implementation of small-scale, renewable-energy-based, decentralized, on-site treatment methodologies ensure water sustainability in rural areas, where centralized treatment facilities are impractical for application. This review article focuses on the recently reported low-cost purification techniques for recycling wastewater generated by single and community-based households in sparsely populated areas. Here we propose treatment technologies for efficient waste management that can be easily integrated in the upcoming years to the lavatories built under the Swachh Bharat Mission (SBM), a momentous cleanliness campaign that has been successfully implemented by the Government of India (GOI). Specifically, we suggest an electrochemical (EC) method to treat the supernatant of the Blackwater (BW) to produce purified non-potable water for reuse in diverse purposes. The EC technique does not require external chemicals for treatment and can be powered by sustainable technologies (like solar panels), thus reducing the treatment cost. Subsequently, vermicomposting, microwave, biogas, and phycoremediation methods are considered to treat the solid sludge to produce value-added products such as enriched organic fertilizer for agriculture and biofuel. The above methods also ensure the satisfactory reduction in Biochemical Oxygen Demand (BOD) (>85%) and Chemical Oxygen Demand (COD) (81–91%) and the complete removal of pathogens and other harmful pollutants. Finally, the novel treatment techniques discussed here are not only limited to rural areas of India but can be implemented in any rural area of the world. [ABSTRACT FROM AUTHOR]

Waste management plays key role in the development of a nation. There are many technologies to produce and extract energy. Several investigation has been made for generation of biogas from animal waste. A total of about 89,600 tons of Swine waste is produced per day in India. The characteristics of Swine waste is that it has a low C/N ratio, due to high nitrogen content. This will result in the production of ammonia and it destroys the micro-organisms which is responsible for Biogas production. In order to avoid more production of ammonia, swine manure is combined with cow dung, Food Waste each and water in the ratio of 1:1:4 and 1:1.5:4 at a temperature of 35 o C. This paper attempts to reduce the retention time by self – circulation of slurry by the gravity difference. Also experiment has been carried out in a thermophilic range for effective digestion. Experiments have been carried out in a fixed dome digester and the gas concentration has been continuously monitored by online biogas analyzer. Comparison study was carried out in two different combination of waste at normal methanogenic micro-organisms. [ABSTRACT FROM AUTHOR]

In recent years, lignocellulosic biomass has gotten a lot of coverage, especially for the captured energy through the anaerobic degradation. The conversion of lignocellulosic biomass to biogas through an anaerobic digestion process has been facing challenges such as low biogas production, low buffering ability, poor end quality of products, and potential heterogeneity of biomass which have difficulties to define an optimized unit operation. These deficiencies may be related to the recalcitrant disposition of agricultural wastes or low mass transfer. India has a large amount of lignocellulosic biomass, and this biomass remains unused in the harvested field. However, it has a scope of utilization by conversion into useful biofuel. Furthermore, it could be enhanced the farmer's income as well as helps to contribute reduce the loss of environmental impact. Hence, the present review script discusses the potential, composition, biomethane production, pretreatment methods and technology related to lignocellulosic biomass, challenges, progress, and the latest program initiated in India. However, only 10 major types of lignocellulosic biomass have been reviewed in this paper. [Display omitted] • Lignocellulosic biomass has a scope to convert into biofuel. • The conversion of lignocellulosic biomass to biogas facing some challenges. • Pretreatment necessary for conversion of lignocellulosic biomass to biogas. • Out of all the pretreatments, alkali pretreatment (NaOH) is the most promising. • The combination of two or more pretreatments provides a better result. [ABSTRACT FROM AUTHOR]

The power sector of developing countries is the backbone of the economy, and robust implementation of energy policies can play a significant role in its expansion. India is blessed to have ample natural resources; the only necessity is to identify these unseen resources comprehensively. India is an agricultural country with plenty of livestock generated biomass, which is renewable and easily accessible in rural India. The paper estimated the potential of electrical energy through biogas production from livestock generated dung in all states of India. Estimation of biogas from the gross livestock dung generation from all states and largely populated livestock species of the country is annually 2633 million tons which correspondingly projects the annual biogas potential of 265,542 million m3. This magnificent potential unbolts the proposals and implementation of biogas plants as a distributed generation to strengthen India's power sector. [ABSTRACT FROM AUTHOR]

Abstract: Since 2003 India has been actively promoting the cultivation of Jatropha on unproductive and degraded lands (wastelands) for the production of biodiesel suitable as transportation fuel. In this paper the life cycle energy balance, global warming potential, acidification potential, eutrophication potential and land use impact on ecosystem quality is evaluated for a small scale, low-input Jatropha biodiesel system established on wasteland in rural India. In addition to the life cycle assessment of the case at hand, the environmental performance of the same system expanded with a biogas installation digesting seed cake was quantified. The environmental impacts were compared to the life cycle impacts of a fossil fuel reference system delivering the same amount of products and functions as the Jatropha biodiesel system under research. The results show that the production and use of Jatropha biodiesel triggers an 82% decrease in non-renewable energy requirement (Net Energy Ratio, NER=1.85) and a 55% reduction in global warming potential (GWP) compared to the reference fossil-fuel based system. However, there is an increase in acidification (49%) and eutrophication (430%) from the Jatropha system relative to the reference case. Although adding biogas production to the system boosts the energy efficiency of the system (NER=3.40), the GWP reduction would not increase (51%) due to additional CH4 emissions. For the land use impact, Jatropha improved the structural ecosystem quality when planted on wasteland, but reduced the functional ecosystem quality. Fertilizer application (mainly N) is an important contributor to most negative impact categories. Optimizing fertilization, agronomic practices and genetics are the major system improvement options. [ABSTRACT FROM AUTHOR]

Electrification of villages is a vital step for improving the techno-economic conditions of rural areas and crucial for the country's overall development. The villages' welfare is one of the main aims of the rural electrification programs. Rural electrification is relatively costly compared to electrification of urban areas. Now, the research question is to find the best combinations of HRES from the available resources in a given village location that can meet the electricity demand in a sustainable manner and to see whether this is a cost-effective solution or not. This study is an attempt to structure a model of electricity generation based on multiple combinations of HRES with the application of HOMER energy software at an identified off-grid village location in India. The main objectives of this study are to analyze the best-suited configuration of a hybrid RE system out of various combinations to meet the village load requirement reliably, continuously and sustainably. The study also reduces the total system net present cost and least cost of energy (COE) using multi-objective HOMER Pro software. In this study, a resource assessment and demand calculation have been carried out and the COE per unit has been ascertained for different systems and configurations. A combination of PV–Wind–Biomass–Biogas–FC along with battery has been identified as the cheapest and most dependable solution with a COE of $0.214/kWh. [ABSTRACT FROM AUTHOR]

Modern economies run on the backbone of electricity as one of major factors behind industrial development. India is endowed with plenty of natural resources and the majority of electricity within the country is generated from thermal and hydro-electric plants. A few nuclear plants assist in meeting the national requirements for electricity but still many rural areas remain uncovered. As India is primarily a rural agrarian economy, providing electricity to the remote, undeveloped regions of the country remains a top priority of the government. A vital, untapped source is livestock generated biomass which to some extent has been utilized to generate electricity in small scale biogas based plants under the government's thrust on rural development. This study is a preliminary attempt to correlate developments in this arena in the Asian region, as well as the developed world, to explore the possibilities of harnessing this resource in a better manner. The current potential of 2600 million tons of livestock dung generated per year, capable of yielding 263,702 million m³ of biogas is exploited. Our estimates suggest that if this resource is utilized judiciously, it possesses the potential of generating 477 TWh (Terawatt hour) of electrical energy per annum. [ABSTRACT FROM AUTHOR]

Tanneries in India face the twin problems of managing process solid waste and treatment of effluent plant sludge. The present study covered (i) significance of optimization of mix proportions of substrates i.e., fleshings (F) and the primary sludge (PS) and secondary sludge (SS) generated during treatment of tannery wastewater (ii) residence time during co-digestion for enhancement of biogas generation and (iii) digestate analysis. Maximum biogas generation of 385 mL/g of VS was observed for the mix proportion of 1.00:2.70:0.30 (F:PS:SS) and a residence time of 45 days during co-digestion of tannery solid wastes. Biogas generation was enhanced by increasing the proportion of PS to SS. After digestion, secondary metabolites i.e., primary, secondary, and tertiary alcohols, amino acids, methane, and ammonia were observed from FT-IR analysis. The exothermic reaction was observed at around 175 °C and when C/N ratio of digestate was around 8.0. [ABSTRACT FROM AUTHOR]

The article presents data on household biogas plants successfully established by a non-profit agency in remote tribal villages of western India with an emphasis on their impact in enhancing local ecology and relieving economic stress in rural communities. Results show that this biogas plants provides alternative renewable energy source, which has the potential to significantly reduce pressure on forest, soil and associated terrestrial ecosystems. Researchers conclude that environment-friendly biogas technology deserves attention and should be promoted aggressively throughout the world, including the most and least developed countries.