Question: can you generate energy from talking?

Meggi answered on 5 Jan 2017:

In general yes, but this would not be much energy.

If we take a look at the air flow that comes with talking, we might use that with a specific mask to convert it to energy. The same applies to the movement of the jaw.

I assume you refer to the sound. A direct problem is that the sound energy is not directed and concentrated (when you talk, the person behind you can understand you, basically in a certain radius people can understand you). Collecting all signals is already problematic, which limits the amount of possible energy conversion. Another effect is that with the sound wave causes air vibration which results to heat energy and therefore energy loss of the wave (that is why you cannot here the same person if you go further away).

Overall, yes you can generate energy with your talking. Actually, there are already attempts to convert the sound wave directly into electric energy. Scientists from the Queen Mary University of London have developed a nanogenerator:

The nanogenerator uses the Piezoelectric effect of zinc oxide. Simply said, zinc oxide is able to convert mechanic energy into electric energy. If a “sound” is absorbed, the zinc oxide is deformed and relaxation backwards (mechanic energy) brings the electric energy.

You point out an interesting issue. We have many places with sound energy (cities, parties, football games, traffic…). How could we convert this sound energy into electric energy?