Please go Piezo
Phones that charge themselves up when you talk into them? Now that sounds like a good idea :>) It seems as though the more noise we make the more we can harvest it for energy. And it’s all down to size which has to be really really thin. other uses could make the dance floor green as the energy from the dancers keep the lights flashing.
The technology is being investigated for artificial heart pumps that can take their energy from the beating of the heart.