Bacteria used to convert solar energy into liquid fuel
Biologists from Harvard University have developed a way to make burnable liquid fuel out of sunlight, using an artificial leaf and a bucket of bacteria-infested water.
According to the Capital OTC, the research team developed an artificial leaf which can make sunlight divide water into oxygen and hydrogen. This process uses bacteria specially engineered to convert carbon dioxide and hydrogen into isopropanol, which is a type of liquid fuel.
Professor Pamela Silver, one of the researchers involved in the study and scientist specialized in biochemistry and systems biology at Harvard Medical School, explained that the new discovery proves that it’s possible to have liquid fuel by harvesting solar energy.
Professor Silver said that they are trying to develop an easy way of obtaining fuel using natural methods.
The artificial leaf was invented by Daniel Nocera, professor of energy at Harvard. According to him, this special leaf requires inexpensive materials to act as catalysts and convert solar energy into fuel.
Professor Nocera explained that the catalysts he’s invented are very adaptable and have a high level of compatibility with the conditions needed for the bacteria to thrive.
In this new system, Nocera says, once the artificial leaf succeeded in producing oxygen and hydrogen, the hydrogen is then used to feed a bacterium called Ralstonia eutropha.
After this process, the hydrogen is taken back to protons and electrons by an enzyme, combining them with carbon dioxide in order for them to replicate, which leads to the formation of more cells.
The next step is based on the discoveries made previously by Anthony Sinskey, professor of microbiology, health sciences and technology at The Massachusetts Institute of Technology.
This next step involves the bacterium being metabolically engineered in order to make isopropanol.
Professor Silver said that these principles could also be used to produce vitamins in a small amount.
The team of scientists wanted to increase the ability of the artificial leaf to convert solar energy into biomass by optimizing the bacteria and the catalyst.
The scientists’ goal is to achieve an efficiency of 5%, while nature’s rate of efficiency for turning sunlight into biomass via photosynthesis is of 1%.
The new study was published in the journal PNAS.