Here’s what you need to know about how electricity flows.
How Generators Work
What sends the electrons into motion? The physics are complicated, but in essence, electrical flow in circuit wires is made possible by a utility generator (a turbine powered by wind, water, an atomic reactor, or burning fossil fuels). In 1831, Michael Faraday discovered that electrical charges were created when a material that conducts electricity (metal wire) is moved within a magnetic field. This is the principal by which modern generators work: The turbines—whether powered by falling water or steam created by nuclear reactors—rotate huge coils of metal wire inside giant magnets, thereby causing electrical charges to flow. With this massive electrical field of positive and negative charges established, the electrons in the wires throughout the power grid jump into action and begin to flow in cadence with the electrical field. When you flip a light switch or plug in a lamp or toaster, you are actually tapping into a large utility-wide flow of electrons being pulled and pushed by utility generators that may be hundreds of miles away. Electrical generators are sometimes likened to water pumps—they do not create the electricity (just like a water pump does not create water), but they make the flow of electrons possible.
AC vs. DC Current
Electrical current exists in two types: alternating current (AC) and direct current (DC). Technically, DC current flows in one direction only, while AC current reverses direction. In everyday terms, AC is the form of generator-created electricity that operates lights, appliances, and outlets in your home, while DC is the form of power provided by batteries. For example, your flashlights are DC systems, while your home’s outlets use an AC system. Many renewable energy sources such as solar and wind generators, produce DC electricity that is converted to AC for use in the home. An automobile’s battery is a DC system used to start the engine, but once the engine is started, the automobile’s electrical system has an alternator that begins to create AC current to run the various systems. Each electrical device, such as a light fixture or appliance, has a rate of usage measured in watts. For example, a 100-watt light bulb burning for 10 hours uses one kilowatt-hour of electricity. Amps, volts, and watts exist in a mathematical relationship to one another, expressed as follows: Watts = Volts x Amps If an appliance is rated at 120 volts and 10 amps, it will use up to 1,200 watts when it is running: 120 volts x 10 amps = 1,200 watts. In circuit wiring, too much resistance can overload a circuit and cause an electrical fire. Because bad connections caused by things like loose screw terminals and corrosion are likely culprits, electrical connections should be checked regularly to ensure safety in an electrical system. If you have any concerns about your electric work or want to be proactive about safety, consider hiring a professional to do a routine check.
