Scientists use algae to power a computer continuously for a year
Researchers have successfully used a widespread species of blue-green algae to power a microprocessor continuously for a year - and counting - using nothing but ambient light and water.
Their system has potential as a reliable and renewable way to power small devices and is comparable in size to an AA battery. It contains a type of non-toxic algae called Synechocystis that naturally 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. The system is made of common, inexpensive and largely recyclable materials.
This means it could easily be replicated hundreds of thousands of times to power large numbers of small devices as part of the Internet of Things. The researchers say it is likely to be most useful in off-grid situations or remote locations, where small amounts of power can be very beneficial.
"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 the University of Cambridge's Department of Biochemistry, joint senior author of the paper.
He added: "Our photosynthetic device doesn't run down the way a battery does because it's continually using light as the energy source."
The work was a collaboration between the University of Cambridge and Arm, a company leading the design of microprocessors. Arm Research developed the ultra-efficient Arm Cortex M0+ test chip, built the board, and set up the data-collection cloud interface presented in the experiments.
