Bacteria Power May Be Key Energy Source For Space Robots
Be careful not to dose these bacteria with antibiotics. Scientists have experimented with energy-producing bacteria for about a century now, but applications of microbial fuel cell (MFC) technology are just beginning to blossom. According to the US Naval Research Laboratory (NRL), NASA is hoping to use MFCs to power small devices, including 'microrovers,' for use in space.
MFCs work by capturing the ions that bacteria leave behind when they eat, and then running the ions through a resistor to convert them to electricity.
A 1-kilogram prototype microrover was developed by Dr. Gregory P. Scott, a spacecraft engineer at the the NRL who received a grant from NASA to conduct his research. Scott says the work has "a long-term potential for space and robotic applications."
Planetary robotics, the field that this research may revolutionize, is often concerned with machines that need to function by themselves, in harsh environments, for long periods of time. Because the bacteria in MFCs produce electrons automatically and reproduce over time, these devices are extremely reliable. They're also hardy, not needing any oxygen to live and able to survive the low temperatures of deep space. On top of that, they're more efficient than standard lithium-ion batteries because bacteria can be packed together much more tightly.
So far, it seems like a dream come true. But are MFCs the solution to our global energy woes? Not exactly.
The catch is that they don't provide very high power, but this can still come in handy for space robots that are designed to perform simple tasks. And if more energy is needed, MFCs can store energy over time and release a lot of it at once; According to the NRL, "Once sufficient power is stored, the [MFC] system can then discharge this collected energy to activate a more power intensive scientific instrument or to propel the rover forward using a novel tumbling or hopping locomotion system."
So even though they may not be the answer to powering star-fighters or complex droids, MFCs may someday be adopted by NASA to power an army of simple botlings. They could visit reaches of space that humans only dream of, and do it without all the trouble that goes into building a bigger rover; we'll just have to make sure they don't get too small, because, well, bad things might happen.