Researchers at Oregon State University (OSU) have come up with a technological advance that could open the door for a significant decrease in the cost of producing hydrogen for use in automotive fuel cells. Hydrogen is often created in a microbial electrolysis cell (MEC) using a process that involves attaching some type of biological microorganisms -- with the most plentiful source being biowaste products found in municipal waste water -- to the anode of the cell. A current is applied that breaks these organisms down into protons that then travel to the cathode to combine with electrons and ultimately form hydrogen. Normally, the positive and negative poles must be separated by an internal membrane to prevent losing an excessive amount of the newly formed hydrogen to bacterial consumption. However, OSU's membrane-less MEC not only simplifies the fundamental structure, it requires only one sixth of the electricity and permits nearly three times the amount of hydrogen to be "harvested" compared to subjecting this type of biowaste to a less-efficient fermentive process. If that wasn't enough, the process also cleans up the original source water allowing it to be reused.
According to Dr. Hong Liu, assistant professor of biological and ecological engineering at OSU, the membrane-less MEC has the potential to be fine-tuned for even greater efficiencies that will help bring the energy cost required to produce commercial hydrogen even closer to the Department of Energy's $2-$3 per gallon target.