Electric power transmission is the bulk movement of electrical energy from a generating site, such as a power plant, to an electrical substation. The interconnected lines which facilitate this movement are known as a transmission network. This is distinct from the local wiring between high-voltage substations and customers, which is typically referred to as electric power distribution. The combined transmission and distribution network is part of electricity delivery, known as the electrical grid.
The Federal Energy Regulatory Commission (FERC) is the United States federal agency that regulates the transmission and wholesale sale of electricity and natural gas in interstate commerce and regulates the transportation of oil by pipeline in interstate commerce. FERC also reviews proposals to build interstate natural gas pipelines, natural gas storage projects, and liquefied natural gas (LNG) terminals, in addition to licensing non-federal hydropower projects.
The North American Electric Reliability Corporation (NERC) is a nonprofit corporation based in Atlanta, Georgia, and formed on March 28, 2006, as the successor to the North American Electric Reliability Council. The original NERC was formed on June 1, 1968, by the electric utility industry to promote the reliability and adequacy of bulk power transmission in the electric utility systems of North America. NERC's mission states that it is to "ensure the reliability of the North American bulk power system."
A public utility company is an organization that maintains the infrastructure for a public service. Public utilities are subject to forms of public control and regulation ranging from local community-based groups to statewide government monopolies.
In economic terms, electricity is a commodity capable of being bought, sold, and traded. An electricity market, also power exchange or PX, is a system enabling purchases, through bids to buy; sales, through offers to sell. Bids and offers use supply and demand principles to set the price. Long-term contracts are similar to power purchase agreements and generally considered private bi-lateral transactions between counterparties.
The electric power industry covers the generation, transmission, distribution and sale of electric power to the general public and industry. The commercial distribution of electric power started in 1882 when electricity was produced for electric lighting. In the 1880s and 1890s, growing economic and safety concerns lead to the regulation of the industry. What was once an expensive novelty limited to the most densely populated areas, reliable and economical electric power has become an essential aspect for normal operation of all elements of developed economies.
The Electric Reliability Council of Texas, Inc. (ERCOT) is an American organization that operates Texas's electrical grid, the Texas Interconnection, which supplies power to more than 25 million Texas customers and represents 90 percent of the state's electric load. ERCOT is the first independent system operator (ISO) in the United States and one of nine ISOs in North America. ERCOT works with the Texas Reliability Entity (TRE), one of eight regional entities within the North American Electric Reliability Corporation (NERC) that coordinate to improve reliability of the bulk power grid.
A regional transmission organization (RTO) in the United States is an electric power transmission system operator (TSO) that coordinates, controls, and monitors a multi-state electric grid. The transfer of electricity between states is considered interstate commerce, and electric grids spanning multiple states are therefore regulated by the Federal Energy Regulatory Commission (FERC). The voluntary creation of RTOs was initiated by FERC Order No. 2000, issued on December 20, 1999. The purpose of the RTO is to promote economic efficiency, reliability, and non-discriminatory practices while reducing government oversight.
Demand response is a change in the power consumption of an electric utility customer to better match the demand for power with the supply. Until recently electric energy could not be easily stored, so utilities have traditionally matched demand and supply by throttling the production rate of their power plants, taking generating units on or off line, or importing power from other utilities. There are limits to what can be achieved on the supply side, because some generating units can take a long time to come up to full power, some units may be very expensive to operate, and demand can at times be greater than the capacity of all the available power plants put together. Demand response seeks to adjust the demand for power instead of adjusting the supply.
Southwest Power Pool (SPP), manages the electric grid and wholesale power market for the central United States. As a regional transmission organization, the nonprofit corporation is mandated by the Federal Energy Regulatory Commission to ensure reliable supplies of power, adequate transmission infrastructure and competitive wholesale electricity prices. Southwest Power Pool and its member companies coordinate the flow of electricity across approximately 60,000 miles of high-voltage transmission lines spanning 14 states. The company is headquartered in Little Rock, Arkansas.
A NERC Tag, also commonly referred to as an E-Tag, represents a transaction on the North American bulk electricity market scheduled to flow within, between or across electric utility company territories. The NERC Tag is named for the North American Electric Reliability Corporation (NERC), which is the entity that was responsible for the implementation of the first energy tagging processes. NERC Tags were first introduced in 1997, in response to the need to track the increasingly complicated energy transactions which were produced as a result of the beginning of electric deregulation in North America.
The Midcontinent Independent System Operator, Inc., formerly named Midwest Independent Transmission System Operator, Inc. (MISO) is an Independent System Operator (ISO) and Regional Transmission Organization (RTO) providing open-access transmission service and monitoring the high-voltage transmission system in the Midwest United States and Manitoba, Canada and a southern United States region which includes much of Arkansas, Mississippi, and Louisiana. MISO also operates one of the world's largest real-time energy markets.
ISO New England Inc. (ISO-NE) is an independent, non-profit Regional Transmission Organization (RTO), headquartered in Holyoke, Massachusetts, serving Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont.
PJM Interconnection LLC (PJM) is a regional transmission organization (RTO) in the United States. It is part of the Eastern Interconnection grid operating an electric transmission system serving all or parts of Delaware, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia, and the District of Columbia.
The electricity sector of the United States includes a large array of stakeholders that provide services through electricity generation, transmission, distribution and marketing for industrial, commercial, public and residential customers. It also includes many public institutions that regulate the sector. In 1996, there were 3,195 electric utilities in the United States, of which fewer than 1,000 were engaged in power generation. This leaves a large number of mostly smaller utilities engaged only in power distribution. There were also 65 power marketers. Of all utilities, 2,020 were publicly owned, 932 were rural electric cooperatives, and 243 were investor-owned utilities. The electricity transmission network is controlled by Independent System Operators or Regional Transmission Organizations, which are not-for-profit organizations that are obliged to provide indiscriminate access to various suppliers in order to promote competition.
Open Automated Demand Response (OpenADR) is a research and standards development effort for energy management led by North American research labs and companies. The typical use is to send information and signals to cause electrical power-using devices to be turned off during periods of high demand.
In the electric power industry, a transmission service request is an application requesting a transmission-owning utility to allocate physical capacity in the form of transmission service rights (TSRs) for the transmission of electric power. Every TSR includes at least three components: 1) a point of delivery (POD), where the power is injected into the utility's transmission network; 2) a point of receipt (POR), where the power is withdrawn from the utility's transmission network; 3) the amount of power, or capacity, in megawatts to be reserved. In order to receive TSR, a transmission customer (TC) must complete a transmission service request and go through a system impact study to determine if the existing transmission facilities can reliably accommodate the physical transfer of the electric power. If the capacity is not available, the transmission customer may decide to pay to upgrade the transmission network.
The California Independent System Operator (CAISO) is a non-profit Independent System Operator (ISO) serving California. It oversees the operation of California's bulk electric power system, transmission lines, and electricity market generated and transmitted by its member utilities. The primary stated mission of CAISO is to "operate the grid reliably and efficiently, provide fair and open transmission access, promote environmental stewardship, and facilitate effective markets and promote infrastructure development." The CAISO is one of the largest ISOs in the world, delivering 300 million megawatt-hours of electricity each year and managing about 80% of California's electric flow.
The electrical power grid that powers Northern America is not a single grid, but is instead divided into multiple wide area synchronous grids. The Eastern Interconnection and the Western Interconnection are the largest. Three other regions include the Texas Interconnection, the Quebec Interconnection, and the Alaska Interconnection. Each region delivers power at a nominal 60 Hz frequency. The regions are not usually directly connected or synchronized to each other, but there are some HVDC Interconnectors. The Eastern and Western grids are connected with 1.32 GW.
