Electricity is generated by converting other forms of energy, primarily through the use of a turbine generator set.
The Core Process: Mechanical to Electrical Energy
According to the Alternative Fuels Data Center, to produce electricity, a turbine generator set converts mechanical energy into electrical energy.
Think of it this way:
- A force is used to spin a turbine (a wheel with blades). This spinning is the mechanical energy.
- The turbine is connected to a generator.
- The generator contains magnets and coils of wire. As the turbine spins, it causes the magnets and coils within the generator to move relative to each other.
- This movement creates an electric current in the wires – generating electricity.
Powering the Turbine
The most common way to get the turbine to spin is by using steam. Many power plants heat a working fluid (usually water) until it turns into high-pressure steam.
As noted in the reference:
In the cases of natural gas, coal, nuclear fission, biomass, petroleum, geothermal, and solar thermal, the heat that is produced is used to create steam, which moves the blades of the turbine.
Here's a breakdown of how different sources achieve this heating:
- Fossil Fuels (Natural Gas, Coal, Petroleum), Biomass: These fuels are burned to heat water and create steam.
- Nuclear Fission: The splitting of atoms generates heat, which is used to create steam.
- Geothermal: Heat from within the Earth's core is tapped to create steam or heat a working fluid to power the turbine.
- Solar Thermal: Concentrated sunlight heats a fluid to generate steam.
Other methods exist that don't directly use steam, but still power a turbine:
- Hydroelectric: Falling water spins the turbine directly.
- Wind: Wind turns the blades of a wind turbine, which is connected to a generator.
Overview of Electricity Generation Methods
| Energy Source | How Heat is Produced | Powers Turbine By... |
|---|---|---|
| Natural Gas, Coal, Biomass, Petroleum | Burning the fuel | Creating Steam |
| Nuclear Fission | Splitting atoms (nuclear reaction) | Creating Steam |
| Geothermal | Earth's internal heat | Creating Steam |
| Solar Thermal | Concentrating sunlight | Creating Steam |
| Hydroelectric | N/A (Uses kinetic energy of water) | Falling Water |
| Wind | N/A (Uses kinetic energy of wind) | Moving Air |
In summary, electricity is primarily generated by turning a turbine, which in turn powers a generator to convert mechanical motion into electrical energy. For many common sources, this turbine is driven by steam produced from various heat sources.
