With a population of 7.8 billion, the world produces 3.5 million tonnes of garbage every day. About 0.1 million tonnes are produced in India alone. As communities continue to generate waste, where will all our trash go? Well, Shaktistellar, a Bhopal-based startup focussed on providing sustainable living solutions, has developed a solution for this—Portable Biogas Units.
These units or ‘digestors’ convert your kitchen waste into cooking gas, thereby disposing of waste safely and hygienically, and reduce also a family’s LPG need by half.
“An average Indian family consumes one cylinder a month, which is 12 in a year. According to government provisions, only 6 cylinders are provided at a subsidized price of Rs 400, the other 6 months, it costs Rs 700-800. If a portable biogas unit is installed in homes, families will spend 2400 for the first 6 months on LPG and use biogas, to power the stove, for the next six months. This way, they can save an average of Rs 4800” says Ankit Roy, who along with Praveen Modi, is the co-founder of Shaktistellar.
There’s an interesting story behind Shaktistellar’s founding. After passing out from National Institute of Technology (Bhopal) in 2012, Roy started working with a company in Mumbai where he was closely involved in the power sector, and the job made him want to explore sustainable energy solutions for homes.
In 2016, he moved back to Bhopal and soon, began the process of installing a solar panel on his rooftop. However, the Electricity Board of Madya Pradesh got wind of it, reached his place and asked him to halt the project.
“They were not happy to see what I was doing and asked me to uninstall the grid from my roof because it was against the law. But I was familiar with rules and regulations pertaining to renewable energy, so I wrote a letter to the Ministry of New and Renewable Energy, which, in turn, led to a series of amendments in Madhya Pradesh’s policy for the same. This victory encouraged me to start a company that offers an all-around sustainable living solutions,” says Ankit with a smile.
Established in 2017, the startup was initially bootstrapped, but in 2019 they received a grant from Scotland India Impact Link for Social Enterprise. Apart from the portable biogas digester, Shaktistellar also offers Solar Rooftop installations, E-Vehicle conversions and rainwater harvesting solutions.
“Currently, we cater to places in and around Bhopal that are accessible by road. The raw materials are carried in a truck that we rent and the installation is done by myself and my team,” says Roy.
How Does The Biogas Unit Work?
The biogas unit requires a free space of 1.2 square meters and can be installed anywhere—in the backyard, terrace, or balcony.
It comes with a digestion tank in which everyday kitchen waste is dumped and converted into gas. There are two kinds of tanks—of a 3 litre capacity and 5 litre capacity, respectively. While the former costs Rs 40,000, the latter costs Rs 51,000.
First, the ‘digester’ is fed with kitchen-waste, such as vegetable and fruit peels, leftover foods and more.
“As an additional feature to ensure the waste decomposes faster, a mixer system crushes all the waste that is dumped. If there are any hard metals or stones, the motor will immediately stop and the particle has to be removed manually from between the blades,” says Ankit.
For obtaining the right bacteria to digest the waste, cow dung is required. “This is added only the first time to trigger anaerobic decomposition. Further on, only waste can be added every day into the digester,” he says.
In urban areas, it is hard to find fresh dung. So, dry cow dung is mixed with water, converted into a paste, and is added as a starter.
“The dry dung is procured from a plant that manufactures briquettes in Bhopal,” he says.
Within 10 to 15 days, decomposition takes place and methane gas rises within the chamber while the mushy-waste known as slurry settles at the bottom. “The number of days for the waste to decompose depends on the weather too. In summer it will take only 10 days but during monsoon, it may take more than 15 days,” says Ankit.
Finally, this gas rises into a fibre dome placed above the digestion chamber. The chamber exerts pressure over the gas and pushes it through an outlet, which is connected to the gas-stove in the kitchen.
What is left behind in the digester tank will continue to decompose further waste. What’s more, the slurry left behind can also be used as a manure for plants.
How Long Can I Cook Using The Biogas Unit?
The 5-litre tank offers a continuous gas supply for 5 hours while the 3-litre tank can run for 2.5 hours. “The unit is also equipped with a gas level indicator, which helps monitor the quantity,” says Ankit.
Kailash Narayan Nayak, a resident of Chunabhatti, Mumbai, who installed Shaktistellar’s 3-litre biogas unit in his house, is very happy with its performance.
“For the last 6 -7 months, my family and I have been using the biogas stove. Though the flame is not too strong, it works just perfectly to make rice, roti, sabzi and other basic food items. It has helped us save money. And the environment from a lot of waste. Apart from the gas, I also use the slurry as manure for my garden.
Apart from home users, the biogas unit supports industry requirements too. Some of their clients include—Samrat Ashok Technological Institute, a commercial hostel, and an army regiment hostel.
In the future, Ankit and his team are planning for a Series A funding to enhance and expand their business to other cities.
(Edited by Gayatri Mishra)