Inspired by the way plants turn sunlight into food through photosynthesis researchers at the University of Cambridge have pioneered a floating artificial leave that can convert sunlight and water into clean fuel.
The low-cost autonomous devices trialled on the River Cam have showed they can match the efficiency of plants; doing the same on a large scale at sea would be truly transformational.
“Many renewable energy technologies, including solar fuel technologies, can take up large amounts of space on land, so moving production to open water would mean that clean energy and land use aren’t competing with one another,” said Professor Erwin Reisner. “In theory, you could roll up these devices and put them almost anywhere, in almost any country, which would also help with energy security.”
The latest version of the artificial leave, which has been in the works since 2019, looked to the electronics industry and the ‘miniaturisation techniques’ it has mastered to make smartphones.
“If we can trim the materials down far enough that they’re light enough to float, then it opens up whole new ways that these artificial leaves could be used,” adds Reisner.
Key to the Cambridge team was finding a way to protect the light absorbers from water, which it achieved using ‘water-repellent carbon-based layers’.
“Solar farms have become popular for electricity production; we envision similar farms for fuel synthesis,” said Dr Virgil Andrei from Cambridge’s Yusuf Hamied Department of Chemistry, the paper’s co-lead author. “These could supply coastal settlements, remote islands, cover industrial ponds, or avoid water evaporation from irrigation canals.”
The results are reported in the journal Nature.