There is “green energy” and more really GREEN Energy, or rather, blue-green energy. A colorful colony of photosynthetic cyanobacteria known as blue-green algae has successfully powered a computer microprocessor for more than six months published a study Thursday in the journal Energy & Environmental Science.
The small bio-based battery alternative could serve as a way to power small electronics without rare earth elements and lithium materials in short supply and under growing demand, according to the study researchers. In addition, the system could also help bridge the electricity gap and provide another power supply for people in rural or low-income countries, the senior author said Chris Howea biochemist at Cambridge University, in a press release.
During a pandemic lockdown, the algae computer system was placed in the window of another Cambridge biochemist, home of Paolo Bombelli. It sat there from February to August 2021 and was reportedly working all the time reporting from New scientist. At the six more months to come the official Tests, the scientists said the algae device and the computer kept walking.
Although the microprocessor has since been disconnected, the cyanobacterial device continues to produce electricity. “It’s still going and I hope it will go on for a very long time. given With the right light, temperature and water conditions, I can’t predict when it will stop,” Bombelli said in an email to Gizmodo. Why Gizmodo says: Way to go microbes!
Cyanobacteria get energy from sunlight and use it to make food for themselves. For this study, the researchers used the electricity-supplying microorganisms (specifically Synechocystis sp.) in a plastic and steel case about the size of an AA battery, along with an aluminum anode.
Throughout the experiment, the attached microprocessor was programmed to perform a series of calculations and then check its own work. This happened in 45-minute increments, followed by 15 minutes of standby for months on end with the cyanobacteria unit as the sole power source.
The researchers proposed two hypotheses about how their system generated electricity. In the so-called “electrochemical” model, the microbes simply created the right conditions for the aluminum anode to oxidize — or release electrons, which then produce an electrical output. In the “bioelectrochemical” model, the cyanobacteria themselves generated electrons, which were transferred across bacterial membranes to the aluminum anode, generating a current. Because the aluminum anode didn’t seem to degrade much over time, the scientists think the latter explanation is more likely than the former.
Although the algae depend on a light source to feed themselves, the biosystem continued to produce enough energy to run the microprocessor in the dark. The scientists essentially attributed this phenomenon to food leftovers. When it was light, the cyanobacteria cooked up a glut of food, and when it was dark, the microorganisms munched on the extras.
The computer, a microprocessor called Arm Cortex-M0+, drew an average of 1.05 microwatts and an electrical current of 1.4 microamps at a voltage of 0.72 V from the cyano cube over the course of the experiment. For comparison, a standard AA battery starts life at 1.5V, which decreases with use.
Although the results of the experiment are promising, it’s important to remember that the tested computer processor consumes very little power – it only requires 0.3 microwatts to operate. An energy-efficient LED light bulb is even used for context 10 watts. More research is needed to know exactly how much the tiny AA battery-sized device could scale up. Howe tells New scientist. “Installing one on your roof is not going to provide power to your home at this point.”
Update 5/13/2022 5:08pm ET: This post has been updated with additional comments from biochemist and study researcher Paolo Bombelli.