Blue-green algae powers microprocessor for over a year

Developed in a collaboration between Cambridge University and ARM, the system could provide a reliable and renewable way to power small devices.

Comparable in size to an AA battery, the power source contains Synechocystis, a type of non-toxic algae that harvests energy from the sun through photosynthesis. The tiny electrical current this generates then interacts with an aluminium electrode and is used to power a microprocessor.

It is made of common, inexpensive and largely recyclable materials and could be replicated hundreds of thousands of times to power large numbers of small devices as part of the Internet of Things. The researchers said it is likely to be most useful in off-grid situations or remote locations.

“The growing Internet of Things needs an increasing amount of power, and we think this will have to come from systems that can generate energy, rather than simply store it like batteries,” said Professor Christopher Howe in Cambridge University’s Department of Biochemistry, joint senior author of the paper.