Green Initiative: With new projects, 3 Kolkata colleges turn waste into fuel

Indian Express

3 days ago

In a major push towards sustainable energy, NRS Medical College, Calcutta Pavlov Hospital, and Adyapeath Annada Polytechnic College have successfully launched a pilot project that turns kitchen waste into biogas to run their canteens.
Guided by the West Bengal Renewable Energy Department, the initiative is already showing results, saving on fuel costs and cutting down harmful emissions. Biogas is produced when organic matter like leftover food and vegetable waste is broken down by microorganisms in the absence of oxygen, a process known as anaerobic digestion. What's left behind is a slurry that works as a natural fertilizer for farming and also as feed in fishery. The three institutions now use this green fuel directly in their kitchens, reducing dependence on expensive LPG.
A senior official from the Renewable Energy Department said the idea stemmed from the growing burden of waste disposal in large establishments like hospitals, malls, and hotels.'Nowadays, LP gas which is generally used for cooking is very costly. Biogas can be easily replaced with LP gas with less cost.'
The senior official said that, due to inadequate waste management infrastructure and rising volumes of waste, the problems have become acute, ranging from foul-smelling garbage piles to unreliable collection systems and logistical challenges.
He added that untreated organic waste dumped in landfills leads to dangerous methane emissions and environmental contamination. 'The disposal problems of organic waste are twofold. Firstly, organic materials cause severe environmental problems through methane emission in landfill applications.
Secondly, disposed organic waste is the prime source of diseases and contamination of air and water.'
Methane, according to the Intergovernmental Panel on Climate Change, is 21 times more harmful than carbon dioxide. Biogas production not only prevents such emissions but also creates a cleaner environment.
According to the energy department sources the biogas plants at NRS and Pavlov hospitals were installed on March 25, each with a 250 kg daily waste capacity and a five-year maintenance plan. The plant at Adyapeath Annada Polytechnic College was completed earlier this month. Together, the three projects cost over Rs 50 lakh. Every day, the kitchens feed 250–300 kg of waste, such as vegetable scraps, rice slurry, and leftovers, into the digesters. This produces between 15 and 25 cubic meters of biogas, depending on the volume of input, which is then piped directly to the kitchens. The nutrient-rich slurry left behind is used in the institutions' gardens.
Prasenjit Ghosh, kitchen manager at the NRS canteen, said the system is not only cost-effective but also keeps the hospital surroundings clean. 'This is a very useful project. We are getting energy from waste. It gives us profit in two ways, clean premises and green fuel,' he said.
Debashish Goria, a technical expert involved in the project, explained that 100 kg of biodegradable waste can produce around 10 cubic meters of methane gas—equivalent to 4 to 5 kg of LPG. With more waste, the system can generate the equivalent of up to 30 kg of LPG, offering significant savings and energy security.
West Bengal Health Secretary Narayan Swaroop Nigam expressed his satisfaction with the performance of the green kitchens. 'We're happy with the results at NRS and Pavlov hospitals. It is a step towards a cleaner and greener future. We are planning to expand the project to other hospitals as well,' he said.
Atri Mitra is a Special Correspondent of The Indian Express with more than 20 years of experience in reporting from West Bengal, Bihar and the North-East. He has been covering administration and political news for more than ten years and has a keen interest in political development in West Bengal.
Atri holds a Master degree in Economics from Rabindrabharati University and Bachelor's degree from Calcutta University. He is also an alumnus of St. Xavier's, Kolkata and Ramakrishna Mission Asrama, Narendrapur.
He started his career with leading vernacular daily the Anandabazar Patrika, and worked there for more than fifteen years. He worked as Bihar correspondent for more than three years for Anandabazar Patrika. He covered the 2009 Lok Sabha election and 2010 assembly elections. He also worked with News18-Bangla and covered the Bihar Lok Sabha election in 2019. ... Read More