A hydroelectric dam converts the motion energy of water flowing downhill into electrical energy through mechanical turbines. The water flowing downhill expends the gravitational energy it stored when it was deposited up in the mountains. The water got from the ocean to the mountaintop via thermal energy, which evaporated it into the air to accumulate in clouds and rain. The thermal energy accumulated in the water when it absorbed the Sun’s radiant energy.
The motion energy of a car driving down the street comes from the mechanical energy that makes the wheels go round. The mechanical energy is driven by the combustion engine, which converts the chemical energy stored in gasoline to thermal energy, which expands the air and drives the pistons. The chemical energy stored in the gasoline’s hydrocarbons comes from plants, which converted the Sun’s radiant energy to chemical energy through photosynthesis.
It was the kind of thing my father would have talked about: “What makes it go? Everything goes because the sun is shining.” And then we would have fun discussing it:
“No, the toy goes becaues the spring is wound up,” I would say.
“How did the spring get would up” he would ask.
“I wound it up”
“And how did you get moving?”
“And food grows only because the sun is shining. So it’s because the sun is shining that all these things are moving” That would get the concept across that motion is simply the transformation of the sun’s power.
– Richard Feynman, Energy in Textbooks
Note: Nuclear Energy and bacteria that live off chemical energies would be exceptions to the Sun-origin of all energies for this game. : )