Generating Electricity

1. Generating Electricity

2. What Is Energy? • Energy has many different forms. • When an object is able to change its environment, we say the object has energy. • Energy is the ability to do a task, such as moving an object.

3. Common Forms of Energy

4. Energy Transformations • There are many ways to change or transform one form of energy into another form. • Your body and a car’s engine change chemical energy into mechanical energy. • When you bang a drum, the mechanical energy is changed into sound energy. • A wind turbine changes mechanical energy into electrical energy.

5. Examples of Energy Transformations

6. Generating Electrical Energy The Grid: • Most or the electrical energy we use comes to us through the electrical energy distribution grid. • The electrical energy distribution grid is a network that carries electricity from the energy generating station to the consumer.

8. Generators: • Most energy is distributed by the gird is produced in electrical energy generating stations. • These stations use generators. • A generator is a machine that converts mechanical energy into electrical energy.

10. The energy in the wind, flowing water, or stream can be converted into electrical energy. • The movement is used to push blades of a fan-like device called a turbine. • The turbine is connected to the wire coils inside a generator. • When the turbine spins, the coils of a wire generate electrical energy as they spin at high speed near powerful magnets.

11. Measuring Electrical Energy • All energy is measured in joules (J). • How quickly we use electrical energy can be measured as the number of joules used per second. • A joule per second is called a watt (W). • A 20 W bulb uses 20 J or energy per second.

12. A joule is very small, so we often use a much larger unit, the kilowatt hour (kW∙h). • A kilowatt is 1000 W.