> The most popular batteries use chemicals to store the energy. And then when we want to use the energy, we simply draw it back out. This is pretty much how the electrical grid works.
No, electrical grid currently mostly works without batteries. Power stored in batteries which can give it back to grid is several orders of magnitude smaller than what grid transfers. But this may change in future.
> Also, electricity can cause pressure (well can make things expand) [...] I could not find any current use cases for this property, I will have to look further.
Ultrasonic scanners in doctors offices or ultrasonic motors for some camera lenses, or even those sound-playing birthday cards.
> One you’ve seen a million times in the bath, but you never noticed. When bubbles pop, they can cause a small amount of light. This is called Sonoluminescence. They cause a really really small amount of light lasting a few hundred trillionths of a second.
Yeah, but that's not electricity.
I am confused by your statement on this one. Birthday cards use tiny batteries.
> Yeah, but that's not electricity.
Perhaps the science was updated on this, but articles like this say they can get up to 1W out of it. https://physicsworld.com/a/brightest-bubble-bursting-yet/
And piezoelectric buzzers https://en.wikipedia.org/wiki/Buzzer
> but articles like this say they can get up to 1W out of it
Yeah, but they are getting electricity from light, sonoluminescence generates light, not electricity and author even singled out light as being something different than electricity, you can have light from electricity according to him.
Is there anything you know of that does the opposite? Uses pressure to generate electricity?