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Transmission Line and Pipeline Basics

Definitions and types of transmission lines and pipelines.

Energy Transmission Definitions

What Is Energy Transmission?

Energy transmission is the process of moving electrical energy or a gas or liquid energy source (such as oil or natural gas) from its point of generation or extraction to its point of distribution or consumption. Electrical energy is transmitted via transmission lines, while liquids and gases are transmitted through pipelines.

What Is a Transmission Line?

A transmission line is a set of conductors, insulators, support structures, and associated equipment used to move large quantities of electric power at high voltage, usually over long distances between substations.

What Is a Pipeline?

A pipeline is all parts of the physical facility through which liquids or gases such as crude oil and natural gas are moved, usually over long distances between a producing region and a local distribution system.

Types of Transmission Lines and Pipelines

What types of transmission lines are there?

There are two major types of transmission lines: alternating current (AC) and direct current (DC). However, they have a variety of voltages (generally between 115 and 765 kV) and configurations.

What Types of Pipelines Are There?

There are three major types of pipelines used to transport hydrocarbons: crude oil, natural gas, and product pipelines. There are three components of a natural gas pipeline system: the gathering system, the interstate pipeline, and the distribution system.

Although the information presented in this section is based on the attributes of crude oil pipelines and interstate natural gas pipelines, in general terms, the information about impacts and mitigation measures would be applicable to any type of pipeline.