500 litres of water enough for this bio-toilet to serve a family of five for 15 years

Researchers from IIT-Kharagpur develop a bio-toilet that recycles water and turns waste to energy

By Isha Bajpai
Last Updated: Tuesday 03 April 2018 | 07:04:32 AM
A prototype of the bio-toilet constructed by the research team of IIT-Kharagpur.
A prototype of the bio-toilet constructed by the research team of IIT-Kharagpur. A prototype of the bio-toilet constructed by the research team of IIT-Kharagpur.

With an aim to "provide a solution to the commoners", a research team from Indian Institute of Technology (IIT), Kharagpur has developed a bio-toilet that can not only serve its obvious purpose but also recycle waste water and generate energy from waste. One toilet will just require 500 litres of water once and it can function for the next 15 years when used by a family of five.

Researchers from IIT-Kharagpur receiving Swachh Bharat award from Union Science & Technology Minister Harsh Vardhan. Credit: IIT-Kharagpur

Recently, this innovation received Swachh Bharat award. “This bio-toilet will generate electricity and reduce water consumed in toilets. The power it generates can light up the washrooms in the night and in the day it can be used to power up small electronic appliances like a mobile or other batteries,” said Dr Makarand M Ghangrekar, project leader and professor of civil engineering. “When it comes to water, it will reduce the usage substantially. Currently, 10-15 litres of fresh water gets wasted every time we use a toilet, but with this bio-toilet that can be cut to 1-2 litres of recycled water.”


The IIT-Kharagpur professor says that the toilets the central and state governments have built will not solve the environmental problem, but only the social problem. Despite the governments constructing crores of toilets for people living in rural areas, they are still unused either for the lack of water connection or solid and liquid waste management system. This is where bio-toilets offer a solution.

The electrogenic bacteria present in the septic tank use human waste to generate electricity. Credit: IIT-Kharagpur

“The microbial fuel cell (MFC) reactors used in the setup can completely recycle the water once flushed for more use and that means the toilets don’t require any separate piped water supply. Also, the electrogenic bacteria present in the septic tank will use human waste to generate electricity,” the professor tells Down To Earth. “This project is for places that are away from water and electricity sources,” he adds.


According to the researchers, the cost of each unit is something they need to work on. “The first unit we made after many trials and errors cost us Rs 250,000. The cost of the next one should come down to Rs 1,00,000 or less and if and when we start developing them in bulk the price will further come down,” says Ghangrekar while adding that he and his team have been working on the project for the last 15 years.

Maintenance is another aspect they need to factor in when it comes to product cost since the cathodes in every unit will require attention every six months. They would also need to clean up fungus growth and any unwanted bacteria growth so that it doesn’t stink. “The maintenance cost should be around Rs 2,000,” says the professor of civil engineering .

Road ahead

The research team has partnered with the National Thermal Power Corporation (NTPC) for the project, which is funded by the Department of Science and Technology. The first stage of this partnership will be testing the bio-toilet. It will be installed by April-end at NTPC’s campus in Greater Noida for two years.

Subscribe to Weekly Newsletter :

Related Story:

First-of-a-kind study on community-led sanitation reveals implementation challenges

Delhi HC asks city authorities if there is a policy to dispose toxic e-waste

Unmasking the Budget

SC admonishes Centre for poor affidavit on solid waste management

Budget 2018: To make India open defecation-free, Centre must invest less in building toilets

IEP Resources:

How to reach everyone with safe water and sanitation by 2030

World Water Development Report 2017: wastewater - the untapped resource

Question raised in Rajya Sabha on Status of open defecation in rural areas, 27/03/2017

Draft National Urban Faecal Sludge & Septage Management (FSSM) Policy

Marketing of Bio-Toilets: Opportunities and challenges

Judgement of the National Green Tribunal regarding groundwater pollution caused by effluents discharged from bathrooms and toilets, Muttukadu Village, Kancheepuram District, Tamil Nadu, 10/10/2015

We are a voice to you; you have been a support to us. Together we build journalism that is independent, credible and fearless. You can further help us by making a donation. This will mean a lot for our ability to bring you news, perspectives and analysis from the ground so that we can make change together.

Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.