From garbage to electricity: Goa reaches new waste management milestone
The Goa Waste Management Corporation (GWMC) has reached a significant milestone with the establishment of a 100 tonnes per day (TPD) Integrated Solid Waste Management Plant in Cacora, South Goa. The facility is designed to manage municipal solid waste from both municipalities and panchayats in the region.
The plant is located on a site that was previously an open dumping ground, which has since been remediated and transformed into a modern waste management facility. The state-of-the-art facility was inaugurated by Prime Minister Narendra Modi February 6, 2024.
The Cacora plant is a brownfield project, meaning it was developed on a previously used site. The legacy waste at this location was remediated to recover the land for the new facility. The project is estimated to cost Rs 173.98 crore.
It is based on a public-private partnership model, with the state providing 75 per cent of the funding, supported by a National Bank for Agriculture and Rural Development loan under the Rural Infrastructure Development Fund and the concessionaire providing the remaining through equity. The GWMC has also provided essential infrastructure, including land, access roads, electricity and water connections.
The plant is the second of its kind established by the corporation in Goa, after a solid waste management facility in Saligao, said Ankit Yadav, managing director of GWMC. “The Cacora facility incorporates similar technology and builds on the operational experience of the Saligao plant. The facility adheres to the Solid Waste Management Rules, 2016 and employs a comprehensive approach, including recycling and sorting lines, segregation, biomethanation and composting,” he added.
The operations of the facility are overseen by an expert committee led by Padmashree Sharad Kale, a former Bhabha Atomic Research Centre scientist, with contributions from the National Environmental Engineering Research Institute, Indian Institute of Technology Bombay, Birla Institute of Technology And Science, Pilani and other waste management experts from Goa.
The Cacora facility serves both rural and urban populations in Quepem, Sanguem, Dharbandora and Canacona talukas, covering around 30 village panchayats and four municipal councils. The facility can process 60 TPD of wet waste and 40 TPD of dry waste, resulting in production of recyclables, electricity, compost and liquid fertiliser. This initiative supports India’s Swachh Bharat Mission and Goa’s vision for a Nitol Goem (clean Goa).
The plant’s efficiency is boosted by regular monitoring from an independent committee, resulting in a high biogas yield of 130-140 cubic metres per tonne of segregated municipal solid waste, with methane content at 60 per cent, said Shashank Dessai, plant in-charge at GWMC.
Only 4-5 per cent of processed inert waste ends up in landfills — significantly below the national standard of 10 per cent — and the recovery rate for recyclables is 22 per cent. All wastewater generated from the process is recycled. These achievements are an evidence of the plant’s consistent performance, Dessai added.
Waste collection is initially handled by panchayats and municipalities, which store the waste at secondary points. GWMC then transports the segregated waste using specially designed vehicles.
Upon arrival at the plant, dry waste is directed to a feeding bunker for the segregation of recyclables such as plastic, paper, cloth, metal and cardboard. These materials are then sent to recycling units in Karnataka and Mumbai, while non-recyclable waste is transported to cement industries in Karnataka for co-processing at a cost of approximately Rs 1,500 per tonne.
The plant processes around 60 tonnes of wet, segregated waste daily through a biomethanation process to generate electricity. The thermophilic digester produces 130-140 cubic metres of biogas per tonne of segregated wet organic waste. The facility generates approximately 8,000 cubic metres of biogas daily, which is used to produce electricity through an 800 kilowatt generator.
Currently, the plant produces 17,000 units of electricity daily, with 40 per cent used in-house and the remaining 60 per cent supplied to the grid at a rate of Rs 5 per unit. Additionally, the plant generates 1,600 units per day from solar power and produces 4-6 tonnes of compost daily.
Water is a critical resource for operating the biogas plant, with 1,000 litres required per tonne of segregated wet organic waste. To manage potential water shortages, the plant has a 450 kilolitres per day effluent treatment plant to treat wastewater from the digester, washing units and other sources. The recycled water is reused in the process and for gardening.
The concessionaire is paid approximately Rs 3,000 per tonne of processed waste on a monthly basis, based on performance evaluations according to agreed indicators. User fees are collected by panchayats and municipalities, with no processing costs charged by GWMC. These expenditures are justified by the significant environmental benefits and electricity generation.
A notable feature of the facility is its in-house training and capacity-building programme, aimed at upskilling workers and improving the plant’s operational efficiency. The training centre also educates school and college students. So far, the programme has trained 1,400 school students, raising awareness of waste management challenges and solutions. The cleanliness and hygiene maintained at the facility further distinguish it from other waste management centres.
However, the plant has faced challenges, particularly in maintaining a steady supply of segregated waste needed for the biogas facility. This has been addressed through regular awareness campaigns and enforcement measures, supported by political will and administrative backing.
The Cacora Integrated Solid Waste Management Plant represents a significant step forward in sustainable waste management for South Goa. It addresses the region’s waste disposal needs while contributing to broader environmental goals, providing a model for other areas to follow.