How to we create electricity? * We use substances to generate electricity * Mineral deposit containing combustible substances is considered to be a fossil fuel * Coal is formed from plants that have been fossilized through oxidation. The end result is a black hard substance that gives off carbon dioxide when burned * Coal is currently the most widely used substance to generate electricity and heat. * Due to the harmful gases that it releases into the environment, the use of coal is constantly being reduced as people search out alternative fuels * Coal takes a long time to form
Step-by-step explanation of the process at work to turn raw materials into the power and brings comfort to our lives. 1. Trains and trucks deliver coal to power plants. The plants store the coal in huge piles.
2. Before it can be burned, the coal must be crushed into small piece and sent on a conveyor belt to bins that hold a one- or two-day supply.
3. The crushed coal goes through a pulveriser, where it gets reduced to a fine powder. Mixed with hot air, the powder is blown through coal burners into the boiler furnace. In the furnace, the mixture is ignited and burned at a high intensity.
4. Burning produces a heavy ash, which drops into an ash hopper for disposal. It also produces a lightweight ash, called fly ash that is removed by electric precipitators and mechanical dust collectors before the gases discharge through the chimney.
5. Water flows through thousands of tubes in the boiler furnace. The furnace converts the water to steam, which collects in a steam drum at the top of the boiler. The steam then travels at high pressure through a steam line into the turbines.
6. The steam expands inside the turbines, pushing against blades attached to a shaft. That shaft then starts to spin. A large electric magnet attached to the other end of the shaft spins inside a coil of heavy copper conductors, generating electricity.
7. The generated electricity then goes to step-up transformers where the voltage is increased for transmission through cables.
Electronic Circuits * An electronic circuit is a complete course of conductors through which current can travel * AKA a path from one side of a power source to the other * Circuits provide a path for current to flow * Metals are conductors of electricity * When you touch an electric fence, your providing an alternate pathway from your arm to the ground * Power lines are considered as a circuit
There are 4 main components of a circuit 1. An energy source – e.g. a