From the toilet to the sewage to the bacteria: a new way to extract energy

By Akari Miki

            Organic waste from toilets and kitchens accumulates in the sewer. Extracting it from the wastewater is necessary: it is detrimental to the environment, and more importantly, it can be converted to energy. An ideal method of extraction is cost-effective and does not require an input of energy.

            Researchers at Ghent University in Belgium have found a possible solution called the contact-stabilization process, which uses bacteria. In their research, they starved the bacteria and then briefly exposed them to wastewater. The scientists discovered that the microbes could consume the organic matter without completely metabolizing it, so as the second step, it could be converted to energy. Up to fifty-five percent of the waste could be extracted from sewage with this method, and this is greater than the amount resulting from other existing processes, which is between twenty and thirty percent. Furthermore, the contact-stabilization process does not require external electricity. Companies that purify water, such as DC Water in Washington, D.C., have been enthusiastic about this method and conducted trials. After all, using bacteria to remove organic matter from sewage does not require an input of energy and can even generate it. It is an efficient way to clean the environment and create a renewable source of energy.


Ghent University. (2016, November 24). Binge-eating bacteria extract energy from sewage. ScienceDaily. Retrieved December 4, 2016 from