At a university in South Korea, where human excrement is being utilized to help light a building, using the toilet may pay for your beverage or bananas. Cho Jae-weon, a professor of urban and environmental engineering at the Ulsan National Institute of Science and Technology (UNIST), has created an eco-friendly toilet that is connected to a laboratory and produces biogas and manure using feces.

With a combination of the terms "bee" and "vision," the BeeVi toilet, sends feces into a storage aquifer through a vacuum pump, saving water. Microorganisms break down the waste to methane, which is used to power a gas stove, a hot-water boiler, and a solid oxide fuel cell in the structure.

Cho said, "If we think out of feces, feces has precious value to make energy and manure. I have put this value into ecological circulation."

A postgraduate student Heo Hui-jin stated that, "I had only ever thought that faeces are dirty, but now it is a treasure of great value to me. I even talk about faeces during mealtimes to think about buying any book I want."

According to the environmental engineer, the average individual defecates around 500g each day, which may be transformed into 50 liters of methane gas. This gas can produce 0.5 kWh of power or operate a car for roughly 1.2 kilometers.