1. An Overview of Electricity: from the power plant to your home
Adapted from

2. The Power Plant Remember, energy is merely changing states.
Depending on the type of power plant (hydroelectric, coal, nuclear), the energy is converted from one form (ex. coal) into another (electricity) through various steps
Think of 2 laws of thermodynamics here…how do they apply?
In almost all cases, the power plant consists of a spinning electrical generator.
In most cases, a steam turbine spins the generator.
The steam might be created by burning coal, oil or natural gas or come from a nuclear reactor

3. Power Grid
The energy (electricity) travels from the power plant to various locations via the power grid.
Depending on where you live, power grid distribution lines can be above or under ground.

4. Transmission Substation
After the power plant the AC current of electricity leaves the generator and enters a transmission substation at the power plant.
This substation uses large transformers to convert the generator's voltage (which is at the thousands of volts level) up to extremely high voltages for long-distance transmission on the transmission grid.
Typical voltages for long distance transmission are in the range of 155,000 to 765,000 volts in order to reduce line losses. A typical maximum transmission distance is about 300 miles (483 km).
substation
High voltage transmission

5. The Distribution Grid
For power to be useful in a building, it comes off the transmission grid and is “stepped-down” to the distribution grid (in several phases) at a power substation.
“stepping-down” power reduces voltages via switches, splitters and circuit breakers
The transmission lines entering the substation and passing through the switch tower
The switch tower & main transformer

6. The transformer is the white cylinder
At your home
Depending on the neighborhood, there is a transformer outside every house or every couple houses.
The transformer reduces the 7,200 volts down to the 240 volts that make up normal household electrical service.
The transformer is the white cylinder