Why do rely so much on fossil fuels, instead of renewable energy sources?

Question

Why do rely so much on fossil fuels, instead of renewable energy sources?

Answer 1

Cheapest, if you don't include indirect costs like global warming or dealing with unstable countries.

Cheapest is often the reason to "Why do they..."

Answer 2

The quick answer is that fossil fuels are quick and easy to burn because all that we have to do (though it needs to be processed) is take it out of the ground.

Renewable resources such as trees and solar energy are simply not as "quick."

Solar energy can only be collected when the conditions are right.

Trees (which we burn to make energy in the same way as fossil fuel) take too much time investment because we have to grow them (which depending on the tree could take a decade or more before you get a tree that is worth it to burn) unless we simply chop down existing forests to do it. (such as the rain forest)

Also most existing cars today do not run on anything other then gasoline or diesel. Though people are working on the hydrogen powered car. This change will take a long time to implement and odds are we will not until gasoline prices become unbearable and the ONLY option left is to switch.