Coal

fossil fuel · ancient plants · energy source

Ancient plant layers. Coal formed from plants that died in swampy forests millions of years ago. Over time, layers of dead plants got buried deeper and deeper, and the heat and pressure turned them into the hard black rock we call coal.

From coal forests. Most coal deposits came from huge tropical forests called coal forests that covered large parts of Earth during the Carboniferous and Permian periods, long before dinosaurs went extinct. These massive swamps were perfect for creating the conditions that turn plant material into coal.

Mostly carbon. Coal is mostly made of carbon, the same element found in diamonds and living plants. It also contains hydrogen, sulfur, oxygen, and nitrogen mixed in, which is why different types of coal burn differently.

Heat and pressure. When plants died in those ancient swamps, they first turned into a spongy material called peat. Layers and layers of sediment piled on top, and over millions of years, the weight and heat transformed the peat into solid coal.

Fossil fuel power. Coal is a fossil fuel, meaning it comes from organisms that lived long ago. When we burn coal today, we release the energy that came from the sun that powered those ancient plants millions of years ago.