What is the size of an AA battery and can the ARM Cortex M0 + run for six months? Well … maybe an AA battery, but obviously, it’s not worth mentioning. But Cambridge researchers have created a cell of blue-green algae that can do the job.
As you can see, algae need light, because they generate energy through photosynthesis. However, unlike conventional solar cells, algae continue to produce energy in the dark for at least some time. Most likely, algae store energy during the day and leave it at night to survive naturally occurring periods of darkness.
Generating energy from photosynthesis is not a new concept since photosynthesis releases electrons. A normal cell contains gold electrodes and some types of proton exchange membranes. Below you can watch a video from Cambridge about power generation from photosynthesis. Remember, of course, the Cortex M0 + is capable of very low power operation. Don’t look for that algae-driven spot welder anytime soon.
People tend to rely on electricity as energy, but there are other ways to use photosynthesis. For example, we’ve seen algae fuel in a chicken coop in the past. Not to mention that we’ve seen algae use a robot to power off in fancy and non-electrical ways.