Figures indicate that the world's uptake of renewable energy has finally eclipsed its demand for fossil fuel sources, and now a record-breaking solar device made by Australian scientists could mean a whole new category of clean energy production is just around the corner.
Researchers at Monash University in Melbourne have successfully developed the world's most energy-efficient 'artificial photosynthesis' technique, which effectively mimics plant-based photosynthesis by using solar energy to convert water into hydrogen. The process, which creates hydrogen and oxygen by running an electric current through water, could be used to inexpensively power our homes and cars in just a few years, say the researchers.
"Electrochemical splitting of water could provide a cheap, clean and renewable source of hydrogen as the ultimately sustainable fuel," said Leone Spiccia, lead author of the research, in a statement to the press. "This latest breakthrough is significant in that it takes us one step further towards this becoming a reality."
Success in the field of artificial photosynthesis normally means achieving an energy efficiency of above 10 percent. In this case the team's system goes above and beyond, reaching 22.4 percent. While it's not a particularly massive gain on the previous record – which stood at 18 percent – the Monash team was able to hit its result using nickel as a catalyst. This is significant because previous methods required using precious metals, whereas nickel is inexpensive, abundant, and offers great stability.
"There are many catalysts that are considerably more sophisticated than nickel and often involving obscure and expensive precious metals," said Doug MacFarlane, co-author of the research, in an interview with Ashley Hall at the ABC. "So nickel is a rather ordinary catalyst in many respects expect for one thing, which is that it's cheap. It's an inexpensive metal and it produces a very, very stable action in its water electrolysis cell. So it's an ideal choice purely and simply because of the cost."
Another innovation is that the Monash system can run on river water, which the researchers say will allow it to be implemented easily in a number of geographic locations. The applications for the technology are massive, with hydrogen suitable for powering all kinds of technologies.
"Hydrogen can be used to generate electricity directly in fuel cells," said MacFarlane. "Cars driven by fuel cell electric engines are becoming available from a number of car manufacturers. Hydrogen could even be used as an inexpensive energy storage technology at the household level to store energy from roof-top solar cells."
Thomas Faunce, an expert on artificial photosynthesis from the Australian National University in Canberra, was not involved in the Monash study but says the potential of this research could radically change the way modern society derives its power.
"If we can convert all the human-made structures on the surface of Earth, every road and house and bridge into a structure that does photosynthesis better than plants, then we can take the pressure off nature and we can have distributed food and fuel across the planet," he told Hall at the ABC.
The research is published in Energy & Environmental Science.