Researchers at Ulsan National Institute of Science and Technology (UNIST), in South Korea, have developed a process for turning human waste into biofuel and heat energy.

A waterless toilet system, newly installed in a pavilion on campus, employs a grinding system that converts feces into a dry, odorless material, after which it is transferred to a digestion tank containing thousands of different microbes. The microbes inside the tank then biodegrade the powdered material to generate carbon dioxide and methane. A high-pressure process is then used to extract carbon dioxide to culture green algae for biofuel, while methane is stored for later use as a heating fuel.

UNIST Professor Jaeweon Cho examines green algae from the project. Image credit: UNIST.“Our ultimate goal is not only for the new toilet system to save water and operational costs for wastewater treatment plants, but for us to establish an ecosystem that supports technology innovation and drives economic diversification where human waste literally has a financial value,” says project leader Jaeweon Cho, professor in the UNIST School of Urban and Environmental Engineering.

Separately, Cho has developed a smartphone application that can determine the monetary value of the treated human waste. Using the application, people will soon be able to trade their waste for a virtual or digital currency to use.

“We expect that this will become a pivotal stepping stone in the developing future of many countries facing dangerous sanitation issues and a lack of reliable, affordable energy,” Cho says.