The colony of algae was enclosed in a unit the size of an AA battery.
Image: Paolo Bombelli / Creative Commons

A computer chip was powered by algae for six months.

A colony of blue-green algae was sealed inside a metal enclosure, the size of an AA battery, by researchers from the University of Cambridge. According to New Scientist, the unit was left on a windowsill, where the algae photosynthesized, generating a tiny current of electricity that powered a chip.

The system is only a proof of concept, but its creators hope it could be used in future Internet of Things devices. They say the advantage of using algae over traditional batteries or solar power is that it has a smaller environmental impact and could potentially provide continuous power.

“Our photosynthetic device doesn’t run down the way a battery does”

The 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 just store it like batteries, according to Professor Christopher Howe.

A small amount of electricity was used to carry out very basic calculations by the algae-powered chip. This is a small portion of the electricity needed to run an average PC. If a normal desktop computer consumes 100 watt of power an hour, you would need 333,000,000 algae to run it.

The algae system produced an extremely small amount of power

The researchers behind the project will need to scale up their solution, but they say the basic attributions of algae power generation are heartening. They say that the algae they used did not need to be fed, and that it was able to continue producing power at night based on energy stored during the day.

We thought the system would stop after a few weeks, but it kept going.

Although using algae in this way is definitely unusual, it is also part of a growing area of research called biophotovoltaics.

Although this process is inefficient, advocates say biophotovoltaic energy systems could be cheap to produce and eco-friendly. In the future, giantlily-pads that float on water could be coated in algae to act as mobile power stations.