Researchers at the University of California, Santa Cruz, have recently demonstrated the feasibility of producing hydrogen gas from wastewater and light from the sun. They use energy from the sun in a process known as microbial electrohydrogenesis to extract hydrogen gas from municipal waste water. The study concluded that, “The successful demonstration of such a self-biased, sustainable microbial device for hydrogen generation could provide a new solution that can simultaneously address the need of wastewater treatment and the increasing demand for clean energy.”
We know that water consists of two molecules of Hydrogen coupled with one molecule of Oxygen (H2O). Hydrogen is commonly produced through electrolosys of water, a costly process that requires considerable amounts of electricity. What is exciting about this new breakthrough is its sustainability. The process uses only sunlight and wastewater to produce hydrogen gas, and does not require an external energy source to split the hydrogen and oxygen from water.
Instead, the research team at the University of California, led by Associate Professor Yat Li, developed a solar-microbial device that combines a microbial fuel cell (MFC) with a photoelectrochemical cell (PEC). Electricity is actually generated biologically, as bacteria work on decomposing organic matter in municipal sewage wastewater by the MFC. This biolocially produced electricity, combined with solar energy produced by the PEC, is sufficient to perform the electrolosys to separate hydrogen and oxygen from the wastewater.
The study was published by the American Chemical Society on September 11, 2013 in an article entitled “A Self-Biased Solar-Microbial Device for Sustainable Hydrogen Generation.”