BeeVi, an eco-friendly toilet that utilizes human excrement to create electricity to generate power, was invented by a professor at South Korea’s Ulsan National Institute of Science and Technology (UNIST). Professor Cho Jae-weon created the BeeVi toilet, which has a vacuum pump that transfers human waste into an underground tank. The waste is subsequently converted to methane by microorganisms in the tank, which serves as a source of energy. This energy is used to power a gas stove, a hot-water boiler, and a solid oxide fuel cell at UNIST.
Biogas is created when bacteria break down organic materials in an oxygen-free environment, a process known as anaerobic digestion. Anaerobic digestion is used in biogas systems to recycle organic waste and convert it to biogas. Biogas is made up of around 50% to 70% methane, 30% to 40% carbon dioxide, and trace quantities of other gases. The combustion of biogas produces pressurized gas, which spins the blades of a turbine linked to a generator. Magnets rotate within the generator, forcing electrons in wires to flow and generating an electrical current that generates electricity.
A person defecates almost 500g each day on average. This may be turned into 50 liters of methane gas, which can generate 0.5 kWh of electricity or drive a car for 1.2 kilometers. Ggool, a virtual currency invented by Professor Jae-weon, which the students can earn currency after using the BeeVi toilet. On campus at UNIST, a student can earn up to 10 Ggool each day, which can be used to buy products like freshly made coffee or instant cup noodles, fruits, and books from the campus stores.
Heo Hui-jin, a postgraduate student who has made and spent Ggool, is thrilled about the new attitude he has formed as a consequence of his experience with his own waste. “I used to think feces were dirty, but now I see them as a treasure of immense value,” he adds. “I even discuss excrement at mealtimes to think about buying any book I want.”