"How can hydroelectric energy be considered the result of the sun's and gravitational energy?"

 

With gravity, water can fall and turn generators to make electricity. But what does the sun have to do with making the energy? Wouldn't it just evaporate some of the water?

yep, the sun just evapourates water. however, its where this evapourated water ends up that is important.

 

think about what needs to happen to get the water behind a hydroelectric dam. specifically of the whole water cycle.

 

not going ot answer this directly because it is almost definitely homework.

I'm think that the sun may evaporate some water, which soon precipitates and goes into lakes and oceans, giving them more power to push generators for energy. Also, maybe the sun can melt some ice in certain areas. Then, there will be more water, which adds to forcing generators to turn. I think that's not too bad.