How Does a Generator Work?

Generators are machines that produce electricity by consuming a fuel source or harnessing some other form of energy. But how do they miraculously transform this energy from one form into the usable electricity that we depend on? Well, it isn’t rocket science and it isn’t magic. In fact, it is far simpler than most people realize.

One Simple Principle

At its core, nearly every generator relies on one simple principle: electromagnetic induction. If you pass a magnet over a conductive material (such as a copper wire), the magnetic force will influence the electrons in that material. If you could regularly and repeatedly run a magnet over that wire, the repeated force would generate a regular wave of electrical energy.

To maximize this, engineers figured out that if you make a coil of conductive material (typically some form of wire) and then stick a series of magnets inside it, then spin those magnets, the force will generate electrical energy. Therefore, this is what pretty much every generator is at its core—a magnet that spins inside a coil of wire. However, the magnet will not spin on its own and needs energy to continuously circulate and generate reliable power. This is where the alternative fuel source comes into play.

Small-Scale Generators

Small-scale generators, including those that you might take with you on a camping trip or you might take advantage of in an emergency, utilize an engine to consistently turn the generator motor and create electricity. Gasoline generators are simple—a lawnmower-sized engine crankshaft is attached to the generator motor and continuously produces energy for as long as the engine keeps running. Natural gas motors are similar, only instead of using gasoline, they require a connection to either propane or natural gas for fuel. In either case, larger motors require larger engines to turn them, but in turn, they produce more power.

Large-Scale Generators

Large-scale generators can vary a little bit more. Wind farms collect energy from moving air by forcing the air to turn large windmills. The blades of these windmills are attached to a drive shaft that turns a generator motor to produce energy.

Hydroelectric projects are similar, only instead of using air, they use a different fluid—water. Water flowing with a current possesses a tremendous amount of momentum (anyone who has tried to swim in a rushing river knows just how powerful they can be). A hydroelectric dam forces this flowing water through a turbine. The turbine spins with the water current, turning a generator motor to produce electricity. Because water possesses such a tremendous amount of strength and force, these installations can take advantage of some truly massive generator motors, producing enough electrical energy to power entire cities.

Coal and natural gas generators burn a fuel source to produce heat. That heat is then imbued into water, causing it to vaporize into steam that can then be used to turn a generator through the use of a turbine system. These forms of electrical generation are still pretty common in the United States, but many people want to move away from them because burning fossil fuels creates carbon emissions, and therefore this type of generation isn’t exactly eco-friendly.

There is one other large-scale form of energy generation that depends on this technology, but few people realize it: nuclear power. A nuclear generator forces a thermonuclear reaction that produces an unbelievable amount of heat, and that means water vaporizing becomes remarkably efficient. This quantity of steam can be pressurized to tremendous levels before being forced through massive turbines that are connected to substantial generators. Unlike coal and natural gas, nuclear does not produce any carbon emissions. Likewise, improvements in technology have made this type of generator substantially safer. However, there is always still a risk with these systems, and there is the problem of nuclear waste to have to worry about.

A Word About Solar Power

Solar power is one of the only ways of generating electricity that does not involve the use of a traditional generator system. Instead, these systems produce electricity by directly harnessing solar energy. As light particles collide with the materials in solar panels, they knock electrons free, creating an electrical current that is then used to power your home. While this technology does have its limitations, this total lack of any sort of emissions or byproducts makes solar one of the best and most renewable sources of energy available on the market today.