Many of the world’s smallest organisms have some incredible means of survival. Some soil bacteria, for example, can gobble up hydrogen from the air and use it for fuel.
It’s exactly this microbiological trickery that set researchers from Monash University in Australia on a long path to locating and isolating an enzyme from Mycobacterium smegmatis that processes the consumed hydrogen and outputs it as electricity.
“We’ve known for some time that bacteria can use the trace hydrogen in the air as a source of energy to help them grow and survive, including in Antarctic soils, volcanic craters, and the deep ocean,” said Chris Greening, microbiology professor at Monash and co-lead of this study.
While hydrogen only makes up 0.00005% of the atmosphere, this isolated hydrogen catalyzing enzyme, which the team called Huc, is able to consume it easily.
While bacteria removes 70 million tonnes of hydrogen yearly from the air, the molecular structure of Huc sees the enzyme split the hydrogen molecules to form an electron transport chain, essentially producing an electrical circuit in the cell.
“Huc is extraordinarily efficient,” says lead author Rhys Grinter from the university’s Biomedicine Discovery Institute.
“Unlike all other known enzymes and chemical catalysts, it even consumes hydrogen below atmospheric levels – as little as 0.00005% of the air we breathe.”
Huc offers extremely versatile and lengthy storage, and is like a battery that never runs out of juice – as long as there’s even a tiny amount of hydrogen bouncing around in the air.
It’s a little premature to be celebrating Huc’s imminent commercial success.
While its practical use suggests the first step would be to aim for it serving as battery cells for small devices, such as clocks, LED globes or simple computers, Grinter believes that with time, funding and massively increasing the density of the enzyme, powering a car is a future possibility.
“The key point here is that the energy comes from the hydrogen and Huc acts as a catalyst for its conversion into electricity. To power a car you’d need to provide sufficient mass of hydrogen to provide the energy to move a car. Given the properties of Huc we demonstrate in our paper, we think it could be an ideal catalyst to perform this conversion. However, a lot of technological development would be required to make this a reality.”
“Huc production is readily scalable and it can be generated from simple and cheap raw ingredients, which compares to expensive platinum-based chemical catalysts for hydrogen conversion,” Grinter told New Atlas.
“The cost of manufacturing Huc containing fuel cells is unknown at this stage, but should be comparable to electrical devices of similar complexity, which could make them economically viable.”
“It’s nearly impossible to predict where the next breakthrough will come from. So broadly, sustained funding of high-quality science across disciplines is incredibly important, both to create new knowledge and to develop new useful technologies.”