Generated by converting mechanical energy into electrical energy, electric power stations use either a turbine or an engine to drive an electric generator, typically comprised of a series of insulated coils of wire and an electromagnet. Electricity is generated by converting other sources of energy like coal, natural gas, nuclear power and renewable energy like hydropower, wind and solar, but is itself neither renewable or non-renewable. Electricity travels in a closed loop, or circuit, and can also be produced by the positive and negative charge generated by two different metals in a chemical solution, or a battery.
In order for the electricity generated by power stations to be useful to homes and businesses it must be transmitted, often long distances. To do this efficiently, we rely on transformers, which increase the voltage of electricity generated at power stations. Before electricity is used in homes or businesses, its voltage often must be reduced, requiring another type of transformer, a step-down transformer, and distribution lines that carry electricity at a lower voltage.
The grid is composed of power stations, transmission lines, transformers, sub-stations, and a host of other electricity infrastructures that make the electricity generated in one location instantly available for use in another. More than 75% of the grid’s transmission lines and transformers are at least twenty-five years old, while the average age of power plants in the US is 35 years old. In order to use renewable energy more efficiently, much of the US will need to build additional transmission lines and upgrade existing systems.