Transmission system operator

A transmission system operator (TSO) is an entity entrusted with transporting energy in the form of natural gas[1] or electrical power on a national or regional level, using fixed infrastructure.

The United States has similar organizational categories: independent system operator (ISO) and regional transmission organization (RTO).

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.

To minimize the probability of grid instability and failure, regional or national transmission system operators are interconnected to each other.

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.

Power station Transformer Electric power transmission Transformer
Simplified diagram of AC electricity grid from generation stations to consumers in North America