Where is it found?

Arapahoe Power Plant along I-25 in Denver. This plant burns both coal and natural gas.

Where do we get electricity?

Well, electricity comes out of holes in the wall, correct? True, but what makes electricity, and gets it to those holes?


Electricity is created by generators. These generators convert mechanical, chemical, or other forms of energy into electrical energy. The most common generator is mechanical and creates electricity by rotating a large magnet within a huge coil of wire. Solar generators convert light energy directly to electrical energy.

What drives the generators?

The vast majority of electric generators in the United States use turbines to rotate the magnets within the coil. A turbine is a machine for generating rotary mechanical power from a flowing stream of steam, wind, or water. The gas or liquid flows over blades on a shaft causing it to rotate.

Most turbines are driven by steam. Wind turns large propeller blades that rotate the magnets in the coil. Water flowing through dams drives turbines that rotate the magnets in the coil.

What creates the steam?

The simple answer is heat that boils water, creating steam. The heat is commonly created either by burning coal, burning natural gas, burning oil, or by nuclear fission. Some generators create steam by burning biomass (wood, garbage, etc).

The diagram below illustrates the process. This process applies to coal, natural gas, and biomass.

For more on power generation, visit Andy Darvill’s Energy Resources web site.