Remember Thomas Edison was murdered because he was going to make electricity free for the world. I imagine physics & thermodynamics have some information intentionally kept out as it's probably classified somewhere. I don't mind solar energy solutions that's great I just wish a solar setup could be bought for $100 or less.

There was this youtube video I saw once I shoulda saved it a teenager doing a DIY putting 4 rechargable batteries with some copper, plastic cogs & rubberbands to a usb charger with the circuitry exposed all on a block of wood. The kid would spin the first cog then put the rubber band on it then physics would come in & make the other cogs spin. Once all 4 cogs were spinning the charger would work & you could charge your phone.

It was interesting & it sucks I can't find it again the key to it all was the rubberband it had to be a certain length & thickness that the force of the first cog spinning would keep the rubberband in motion so the other cogs could spin & keep each other in motion so the rubberband never stops moving till you put ur finger in the way.