Beena Patel

Municipal solid waste (MSW) disposal has become major issue for the city of Ahmedabad, India. Development, concentrated population and economic growth have led to a substantial increase of MSW generation. Therefore, the objective of the study was to characterize MSW for selection of waste processing technology. To provide a solution for sustainable processing and for safe disposal of fresh MSW, Abellon Clean Energy Ltd joined forces with Ahmedabad Municipal Corporation (AMC) under Public–Private Partnership (PPP) to establish a 14.9MW advanced controlled combustion-based waste to energy (WTE) generation facility to process and dispose 1000 tons/day of fresh MSW. For waste characterization, samples (n=201) were collected from the Pirana waste dumping site using quadrate sampling method. A yearly weighted average Low Heating Value (LHV) of 9.85/kg and ash content 25.12% for unsegregated MSW makes controlled combustion with electricity generation an eligible technology. After combustion, the waste volume is reduced by 75%. The 14.9MW WTE facility replaces 417 t coal/day, reducing greenhouse gas (GHG) emissions of 300.38 tCO₂eq/day through coal replacement, while avoiding 735.24 t CO₂eq/day on account of landfill emissions from MSW dumping. Waste to energy is the fastest solution to reduce waste volume by generating electricity through reduction of GHG.

Bio-energy crops need to be grown on marginal salt and drought lands in India as per policy. Understanding environmental stress response in bio-energy crops might help in promoting cultivation of bio-energy feedstock on marginal salty and drought land. This is one of the first report for vegetative propagation of Bamboo (Bambusa balcooa) under salt and drought stress to understand antioxidant enzymes’ gene regulations to combat stress through activation of antioxidant enzymes and osmo-protectant molecules to scavenge reactive oxygen species as measured by physiological changes. Morphological, physiological, and biochemical traits were noted as indicators of plant health upon different sodium chloride (NaCl) salt-stress while various drought conditions with correlation analysis. A significant up-regulation of genes related to most of the antioxidant enzymes was observed up to salinity of 14 mS cm^− 1 electric conductivity (EC) at 150 mM NaCl experimental salt stress which declined with higher salt-stress. While in the case of drought-stress, all genes remained up-regulated while proline dehydrogenase (PDH) remained down-regulated up-to 100% drought-stress having 4% soil moisture. The gene expressions of antioxidant enzymes were significantly correlated with their corresponding gene-products namely super-oxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) and ascorbate peroxidase (APX) activities. Biochemical parameters such as, soluble sugar, proline, malondialdehyde (MDA), total amino acids, hydrogen peroxide and electrolyte leakage ratio also showed positive correlation (p = 0.001) with salt condition. Genetic and biochemical test parameters were significantly correlated with physiological attributes of plant health at soil EC of 14 mS cm^− 1 shown as 150 mM NaCl salt stress and 60% drought-stress having 17% soil moisture content, were the optimum stress tolerance limits observed. Application of these data would be useful to cultivate 0.63 million ha of salinity affected land and 10.05 million ha of drought affected land among wastelands in India to meet biofuel need.

Declining fossil fuel and increasing CO2 emissions from non-renewable fuel leading us to climate change which signifies to reduce fossil fuel dependency and promotes bioenergy as renewable. To address such issue Abellon Clean Energy has developed captive farming of B. balcooa for environment friendly bio-energy feedstock cultivation in; 1112, 2223, 2964 and 6175 plants/hectare densities to understand cost of cultivation and its subsequent use in cottage industry, energy substitute and high value products. Farmers’ field trials were also performed as 1112 plants/hectare at three districts of Gujarat. The optimum plantation density was observed to be 1112 plants/hectare at captive and farmers’ field having approximately 57.70 MT/hectare biomass yield with 32-39 USD/MT cost of production. If 5% of waste land of India cultivates B. balcooa, with 50% biomass yield, 67.51 million metric tonne (mMT)/year bamboo biomass can be produced. Bamboos generates worth of 9788 million USD or 7696 million USD yearly from handicraft and construction respectively. Bamboo grown at marginal ecologies can fetch around 12.83 mMT/year from cottage industrial products worth of 16616 million USD reducing bamboo import. Waste from cottage industries can produce annually bio-energy pellets worth of 13987 million USD which could replace 63.18 mMT of coal or 21.60 mMT of LPG. Optionally 7560 million liters/year of bioethanol can be produced out of waste generated from incense stick processing worth 5670 million USD. Further 30% of bamboo from marginal land cultivation can produce 20.25 mMT/year of activated charcoal worth of 34425 million USD. Indirect employment of 8.66 million people is accounted for incense stick, pellet production, logistics, marketing, etc. B. balcooa has potential for carbon sequestration through marginal land development impacting India’s social, economic and environment conditions that also improves soil quality.

Sustainable use of land and water is crucial in the era of climate change. Abellon Clean Energy has established 3 MW solar plant for practicing agricultural under the solar panels to address food and energy security involving a rural community. This innovation is first of its kind named as “solar-agri-electric model.” The water used for washing the solar panels to maintain efficiency by dust removal irrigates agriculture produce under the panels. This gives 24–34 tones/hectare/yr agriculture produced by reusing 78 lakhs liters of water per year and capturing 250 tons of CO2 in vegetables as food. The 3 MW solar project is registered under clean development mechanism (CDM) under United National Framework Convention on Climate Change (UNFCCC) that reduces 0.1 million tonnes CO2 emissions over 25 years vis-a-vis fossil fuels. Around 52 MT/yr post-harvested residues are used for organic fertilizer, composting, and fodder. Compound wall to safeguard the project site allowed creeper vegetables to grow and reduces dust deposition on the panels through wind breaking filtration. This initiative enhanced degree of sustainability along with local employment of 215 people from four villages including 156 women. In India, 1059.64 MW installed solar plants have potential to sequester 1,600,000 tons CO2/year with abilities of 10,000 tons of agricultural produce that could employ 2000 people. Worldwide solar farms have potential to sequester 143,000 MTCO2 through vegetation producing 100,000 MT of agriculture produce annually. Efficient use of natural resources requires facilitation of local/regional policies with reference to climatic condition, agricultural potential, and availability of natural resources.