The bustling Bowenpally Vegetable Market in Hyderabad, India, sells around 1,500 to 2000 metric tonnes of produce daily and generates about ten metric tons of waste.
Instead of bringing these to landfills where they add to the amounts of waste and emit methane, a potent greenhouse gas responsible for 37% of the climate change problem, these tonnes of organic rubbish are taken to the market-owned compressed biogas (CBG) plant.
CS Monitor Reports that every day, leftovers from the market are broken into pieces to convert into usable fuel or biogas. The biogas is used to power the buildings, streetlights and a kitchen that prepares 800 meals daily.
Biodigesters in India are popular
The article says that millions of biogas plants are operating across India, primarily small family plants designed to run on animal manure and medium- and large-scale enterprises that utilize food waste, sewage, and other organic matter.
However, the article notes that biodigester is not a “silver bullet”, but it plays a role in India’s action plan as it tries to wean itself from coal and fossil fuels. Corporations are investing millions into biogas projects in the coming years.
Pros and Cons of Biodigesters
Let’s start with the cons first.
While biogas digesters offer a convenient way to tackle two environmental issues simultaneously – fossil fuel and waste, experts say it should not distract us from building more scalable and permanent climate solutions. Technological advancement is still required to streamline biogas production and make it more scalable for large populations.
Changes in plant temperatures and input materials can cause problems as well. “A minor change would be acceptable by the biological system, but if there is a drastic change … the system will have to be cleaned and started again, which takes time,” says Sydney Lobo, a Mumbai-based international consultant in the clean technology space. “This is the biggest limitation.”
Then there is the issue of obtaining organic waste. In urban areas where separating waste can be costly, it may not be an effective solution.
“Experts say CBG can serve three critical needs of the growing economy: cooking, industrial energy, and transportation.”
While producing biogas as a primary product, it also generates a byproduct called “digestate”, a nutrient-rich byproduct that can serve as a valuable soil conditioner for farmers.
“If the potential is realized, biogas use can accrue additional wide-ranging benefits, including emission reduction, improved public health, reduced use of chemical fertilizers, savings in fertilizer subsidies, and improved soil nutrition,” says Disha Agarwal, a program lead at the Council on Energy, Environment and Water in New Delhi.
Climate and Clean Air Coalition article say that biogas’ ability to cut methane emissions while producing renewable energy makes it an innovative and valuable climate mitigation and adaptation solution.
“Biogas is made when biomass, such as organic waste, manure, food waste, and agricultural residue, is fermented or put through anaerobic digestion. When put in an oxygen-free environment, waste is broken down and produces 50-75 per cent methane gas. This fuel can be burned for refrigeration, cooking, heating, and lighting. It can generate electricity to supply power grids— a critical resource in Africa, Asia, and South America energy-poor areas.”
The Climate and Clean Air Coalition (CCAC) is supporting various efforts worldwide to investigate the role biogas technology can play to help reduce methane and other air pollutants and achieve the Global Methane Pledge goal to reduce methane emissions by at least 30 per cent by 2030.
The article highlights the benefits of biogas in rural and far-flung areas in many low to middle-income countries that rely on burning biomass for cooking and heating.
Switching to biogas can help reduce air pollution and prevent massive methane emissions from organic waste while providing people with a clean energy source.
Yarlagadda, K. (2022, October 13). A street lit by rotten onions? An Indian market embraces biogas. The Christian Science Monitor. Retrieved by https://www.csmonitor.com/World/Asia-South-Central/2022/1013/A-street-lit-by-rotten-onions-An-Indian-market-embraces-biogas
Biogas, a Climate and Clean Air Solution with Many Benefits. (2022, March 7). Climate & Clean Air Coalition. Retrieved from https://www.ccacoalition.org/en/news/biogas-climate-and-clean-air-solution-many-benefits