A team of scientists from Oxford University showed how the natural movement of bacteria could be harnessed to assemble and power microscopic “wind farms” or other man-made micromachines such as smartphone components.
Researchers say these biologically driven power plants could someday be the microscopic engines for tiny, man-made devices that are self-assembled and self-powered – everything from optical switches to smartphone microphones.
Co-author Dr Tyler Shendruk said: “Many of society’s energy challenges are on the gigawatt scale, but some are downright microscopic. One potential way to generate tiny amounts of power for micromachines might be to harvest it directly from biological systems such as bacteria suspensions.”
Dense bacterial suspensions are the quintessential example of active fluids that flow spontaneously. While swimming bacteria are capable of swarming and driving dis-organised living flows, they are normally too disordered to extract any useful power from.
But when the team immersed a lattice of 64 symmetric micro-rotors into this active fluid, the scientists found that the bacteria spontaneously organised itself in such a way that neighbouring rotors began to spin in opposite directions – a simple structural organisation reminiscent of a wind farm.
Shendruk added, “The amazing thing is that we didn’t have to pre-design microscopic gear-shaped turbines. The rotors just self-assembled into a sort of bacterial wind farm.”
