Current piezoelectric systems are made from toxic materials, but the folks at the Berkeley Lab have devised an ingeniously green alternative by creating bacterophages.
The M13 bacteriophage virus normally spends its time infecting and replicating within E. coli bacteria. But it does have a couple of perks including the ability to generate electric current when compressed.
Berkeley Lab scientists shoehorned this virus into battery form by stacking 20 layers of a genetically-modified version of M13 atop a gold substrate and attaching leads. This resulted in a tiny battery that was able to output six nanoamperes at 400 milivolts.
If the technology can be scaled up commercial levels, the possible applications are nearly endless. They could be applied to roads to generate power as cars travel on them, lights, charging your mobile devices as you walk, or even to power a building's electric needs. [Nature - Berkeley Lab via ExtremeTech]