File:Electricity grid simple- North America.svg, 380px, Simplified diagram of AC electricity grid from generation stations to consumers in North America rect 2 243 235 438

Power station A power station, also referred to as a power plant and sometimes generating station or generating plant, is an industrial facility for the electricity generation, generation of electric power. Power stations are generally connected to an electr ...

rect 276 317 412 556

Transformer In electrical engineering, a transformer is a passive component that transfers electrical energy from one electrical circuit to another circuit, or multiple Electrical network, circuits. A varying current in any coil of the transformer produces ...

rect 412 121 781 400

Electric power transmission 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 that facilitate this movement form a ''transmission network''. This is ...

rect 800 0 980 165

desc bottom-left A transmission system operator (TSO) is an entity entrusted with transporting energy in the form of

natural gas Natural gas (also fossil gas, methane gas, and gas) is a naturally occurring compound of gaseous hydrocarbons, primarily methane (95%), small amounts of higher alkanes, and traces of carbon dioxide and nitrogen, hydrogen sulfide and helium ...

European Network of Transmission System Operators for Gas
'' ENTSO-G''. Retrieved: 2 October 2010. or electrical power on a national or regional level, using fixed

infrastructure Infrastructure is the set of facilities and systems that serve a country, city, or other area, and encompasses the services and facilities necessary for its economy, households and firms to function. Infrastructure is composed of public and pri ...

. The term is defined by the European Commission. The certification procedure for transmission system operators is listed in Article 10 of the Electricity and Gas Directives of 2009. Due to the cost of establishing a transmission infrastructure, such as main power lines or gas main lines and associated connection points, a TSO is usually a

natural monopoly A natural monopoly is a monopoly in an industry in which high infrastructural costs and other barriers to entry relative to the size of the market give the largest supplier in an industry, often the first supplier in a market, an overwhelming adv ...

, and as such is often subjected to regulations. In electrical power business, a TSO is an operator that transmits electrical power from generation plants over the

electrical grid An electrical grid (or electricity network) is an interconnected network for electricity delivery from producers to consumers. Electrical grids consist of power stations, electrical substations to step voltage up or down, electric power tran ...

to regional or local

electricity distribution Electric power distribution is the final stage in the delivery of electricity. Electricity is carried from the transmission system to individual consumers. Distribution substations connect to the transmission system and lower the transmission ...

operators. In natural gas business, a TSO receives gas from producers, transports it via pipeline through an area and delivers to gas distribution companies. The United States has similar organizational categories: independent system operator (ISO) and regional transmission organization (RTO).

Role in electrical power transmission

Safety and reliability are a critical issue for transmission system operators, since any failure on their grid or their electrical generation sources might propagate to a very large number of customers, causing personal and property damages. Natural hazards and generation/consumption imbalances are a major cause of concern. To minimize the probability of grid instability and failure, regional or national transmission system operators are interconnected to each other.

Electricity market operations

The role of the system operator in a wholesale

electricity market An electricity market is a system that enables the exchange of electrical energy, through an electrical grid. Historically, electricity has been primarily sold by companies that operate electric generators, and purchased by consumers or electr ...

is to manage the security of the power system in real time and co-ordinate the supply of and demand for electricity, in a manner that avoids fluctuations in frequency or interruptions of supply. The system operator service is normally specified in rules or codes established as part of the electricity market. The system operator function may be owned by the transmission grid company, or may be fully independent. They are often wholly or partly owned by state or national governments. In many cases they are independent of

electricity generation Electricity generation is the process of generating electric power from sources of primary energy. For electric utility, utilities in the electric power industry, it is the stage prior to its Electricity delivery, delivery (Electric power transm ...

companies (upstream) and

companies (downstream). They are financed either by the states or countries or by charging a toll proportional to the energy they carry. The system operator is required to maintain a continuous (second-by-second) balance between electricity supply from power stations and demand from consumers, and also ensure the provision of reserves that will allow for sudden contingencies. The system operator achieves this by determining the optimal combination of generating stations and reserve providers for each market trading period, instructing generators when and how much electricity to generate, and managing any contingent events that cause the balance between supply and demand to be disrupted. System operations staff undertake this work using sophisticated energy modelling and communications systems. In addition to its roles of real-time dispatch of generation and managing security, the system operator also carries out investigations and planning to ensure that supply can meet demand and system security can be maintained during future trading periods. Examples of planning work may include coordinating generator and transmission outages, facilitating commissioning of new generating plant and procuring ancillary services to support power system operation.

Role in gas transmission

A gas TSO works for the functioning of the internal market and cross-border trade for gas and to ensure the optimal management, coordinated operation and sound technical evolution of the natural gas transmission network. Some gas TSOs also provide the marketplace for gas trading.

References

{{DEFAULTSORT:Transmission System Operator Natural gas pipeline companies

Role in electrical power transmission

Electricity market operations

Role in gas transmission

See also

References