Researchers Power an ARM Processor for a Year Using Algae

pcmag.com:

A team of researchers at the University of Cambridge successfully replaced a battery with algae to provide continuous power to a microprocessor.

The tiny system is roughly the same size as an AA battery and runs an ARM Cortex M0+ processor. However, rather than sipping power from a rechargeable battery, the researchers used a non-toxic blue-green algae called Synechoycystis to naturally harvest energy when exposed to the sun through photosynthesis.

The end result is enough natural energy generation to power the ARM chip, but just as importantly, it's a continuous source of power and doesn't drain like a battery does. When the sun comes up, power comes on tap, and when the sun goes down, you may be surprised to find it doesn't stop. The research team believes the algae has enough food left to continue producing power while it's dark.

Professor Christopher Howe from the University of Cambridge’s Department of Biochemistry, and joint senior author of the paper, explained how useful this could be(Opens in a new window), "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."

Testing under natural light in "a domestic environment and semi-outdoor conditions" resulted in continuous power production for six months, at which point the team's paper was submitted for publication(Opens in a new window). But the algae keeps on photosynthesizing, the chip continues to get the power it needs, and it has now been running for a year.

The ability to replace a lithium-ion battery with algae is highly-desirable for IoT devices, especially when you consider that by 2025 it's predicted there will be over