How transmission works
Transmission lines move power from where it’s made to where it’s needed
Electricity is delivered to homes, schools, hospitals, businesses and industries through an integrated system of generation facilities, power lines and substations. Transmission lines carry electricity from where it is generated to where it is needed. The transmission network enables a large amount of power to travel long distances.
The grid assures reliability
Because electricity cannot be stored, it must be generated, transmitted and distributed at the moment it is needed. In the early days of electrification, power plants were small and generated electricity for the immediate area. As demand for electricity increased, larger, more efficient electric generation sources were built, and high-voltage transmission lines were developed to move the electricity over longer distances. To increase efficiency and reliability, the network of high-voltage transmission lines is connected to neighboring systems. These interconnected systems form a grid that allows power to flow from one region to another, improving reliability, lowering costs by providing alternative power paths and providing access to renewable energy resources.
HVDC lines and the transmission grid
High-voltage direct current lines are like an interstate highway for power. They help bolster the electric grid by efficiently moving large amounts of power from point to point.
HVDC lines are a cost-effective, efficient option for moving large amounts of power over long distances. They can easily be added to the electric grid with converter substations and allow the direction and amount of power to be controlled. Instead of the traditional three phases, or three wires, in an alternating current line, HVDC lines use two wires, positive and negative, to move power.