Presentation on theme: "The big three: coal, oil and gas"— Presentation transcript:
1The big three: coal, oil and gas Coal, oil, and gas are fossil fuels, and can be burnt.They are very important because we use them in so many ways.Where do coal,oil and gascome from?
2Billions of skeletons How did they get in the ground You probably know that fossils are very old dead plants and animals found in the ground.Well that’s what fossil fuels are: dead things that have been buried under rock for millions of years.How did theyget in the groundin the first place?
3Old king coal How do we get coal out of the ground? Coal is formed like this:SwampSeaDead plant materialLayers of sand and rockDead plant material gathers as trees die near the coast.The sea floods the swamp so it is covered with sand and mud.Over time weight and heat change the plant material into coal.How do we getcoal out ofthe ground?
4oil and natural gas out of the ground? Valuable oil and precious gasThis is how oil and gas are formed:Long ago millions of tiny sea plants and animals died.Their bodies sank and turned into a slime, which was buried by mud and sand.The mud and sand became rock after millions of years, and the slime became oil and gas, trapped between layers.Layers of mud and sandGasLayers of rockSlime becomes oilHow do we getoil and natural gas out of the ground?
5What’s the big deal with coal? Coal is made into all sorts of products: steel, medicines, plastics, dyes and tar for roads.Coal also helps to make something we use all the time: electricity. Here’s how:Coal is burned to heat water.Steam makes a turbine spin.A generator makes electricity.Electricity travels along cables.How else canelectricitybe made?
6Why all the fuss about oil and gas? Oil and natural gas are fuels. When they are burned they give off heat. They can be used to make engines work, or to heat homes and offices.Oil can also be made into many things: plastic, paints, cleaning products and even clothes!What else isoil used for?
7Something to think about… There are two big challenges with fossil fuels:1. Burning them causes pollution – this can makepeople and animals ill and damage buildings.2. Burning them contributes to global warming– this is affecting the whole planet.How is globalwarming affectingthe Earth?