2. Electrical Energy Transformations: Generation and Use

3. Generating Electricity-Diagram Electric Power Generation and Use: Thermal/ Heat: Kinetic Chemical: Potential Electrical: Kinetic Mechanical/ Rotational: Kinetic Various forms of potential and kinetic energy

4. How can electrical energy be generated? Electrical power plants differ in how they are powered.  Hydroelectric (pressure of water behind a dam)  Nuclear  Solar thermal  Burning coal, oil, or natural gas--MOST COMMON  Batteries  Wind  Tides  Geothermal (heat from earth) Generating Electricity

5. Electric Power Plant: Fuel Electricity

6. Generating Electricity  Fuel/source - Electrons in wires will not move in an organized way without a source of power. (ex. battery, electrical power plant). Usually fuel in modern electrical power plants is oil, coal, or natural gas: chemical potential energy.  Turbine - Consists of 1000’s of moving blades Transfers the energy in moving steam or water into the rotational kinetic energy of a shaft in a generator Ultimately forces wire coils to rotate within a magnetic field in the generator Description of Components:

7. Generating Electricity  Generator - Mechanical energy is converted to electrical energy Thousands of coils of wire spin between the poles of a strong magnet Electricity is generated at at approx. 20,000 volts  Transformer - A device that is used to step-up (increase) or step-down (decrease) voltage Description of Components: Steam Turbine

8. Generating Electricity  Transmission Lines - Carry electric power many miles at high voltages (approx. 760,000 volts) to the appropriate destination  Distribution and Use - Electricity is “stepped-down” or decreased in a distribution transformer to approx. 12,000 volts Voltage is then decreased further; 120 - 240 volt lines extend to homes and buildings where it is used in various forms Electricity is unique because it cannot be stored. It must be produced on demand and used immediately! Load is the amount of electrical demand. Description of Components: