EnGen Roadshow Demo: Hand Crank Generator

How It Works

[demo]
Source: EnGen Roadshow original demo

Generators work on the principal of Faraday's Law of Induction. In the simplest terms, a moving magnetic field will push an electric current through a coil of wire. This generator, built with parts mostly available from a hardware store, spins six magnets by six coils of wire. Each coil has approximately 1000 turns of copper wire, wound around a steel bolt. Each time a magnet passes by a coil, the magnetic field reverses direction, generating electricity.

How It Is Used Today

Nearly all electricity today is produced by spinning coils of wire next to strong magnets. Much effort is put into making efficient generators, but the electricity itself is a result of the mechanical work done in spinning the generator. The spinning, mechanical motion is can be produced by any number of sources. Hydro-electric dams use water pressure to spin turbines. Natural Gas turbines burn natural gas to spin a generator in a Brayton cycle. High pressure steam spins a generator in a Rankine cycle. Steam is produced in a boiler fueled by coal, nuclear power, or concentrated sunlight.

History

Projects You Can Do At Home

Building a generator or electric motor is a moderately difficult project. Materials are readily available, and examples are plentiful, but winding coils of wire is not easy (trust us!). A quick search will reveal lots of examples, but here are a few we like:
http://www.simplemotor.com/
http://fly.hiwaay.net/~palmer/motor.html
http://www.evilmadscientist.com/article.php/HomopolarMotor

Additional Information