Researchers have come up with a sustainable way to generate hydrogen using just seawater, river water and bacteria.
Hydrogen is a potentially valuable energy source, however environmental concerns about using fossil fuels to produce the gas, and about production costs, have limited its application so far.
Previous studies have shown that harnessing the by-products of microbial organic matter metabolism in a device called a microbial electrolysis cell can produce hydrogen gas. But the process requires an additional input of electricity to make it work effectively.
Now, Penn State researchers have found that hydrogen can be produced in a single device by integrating a water-based power supply into the system.
Professor Bruce Logan, of Pennsylvania State University’s Hydrogen Energy (H2E) Center and Dr Younggy Kim have designed a microbial reverse electrodialysis system, containing five pairs of seawater and river water cells separated by thin membranes.
The passage of salt from seawater to river water generated the additional electricity needed to produce hydrogen without the need for fossil fuels, sunlight, or wind.
“The most significant finding is that hydrogen production is possible using readily available and sustainable sources, and with no need for electricity [input],” ABC Science quoted Logan as saying.
The study has been published online in the Proceedings of the National Academy of Sciences.