Where is the energy source of fossil fuels found?

Answer 1

It comes from sunlight originally, since plants formed the original organic molecules.

When dead plants and animals were buried, compressed, and heated, their products (coal, oil, gas) retained the chemical energy stored in their molecules millions of years earlier.

Answer 2

Fossil fuels (coal, oil and natural gas) are a non renewable source of energy.

Answer 3

The energy source of fossil fuels comes from chemical bonds.