Present throughout the electrical system, power substations play an essential role in the correct and safe operation of the electrical grid. Here, the electricity generated in the plants is transformed, controlled and adapted for residential, commercial or industrial use.
What are power substations?
Defined as a set of equipment that adjusts voltage levels between generation and consumers, the main purpose of power substations is to correctly control electrical energy, ensuring safety in distribution and supply. I
n practice, they transform voltage, protect against failures, interconnect networks and monitor the electrical system to ensure efficiency and stability.
Their physical composition is made up of power transformers, lightning arresters, circuit breakers, busbars, disconnecting switches, protection relays, grounding systems and other electrical components, which are crucial for the continuous operation of the electrical grid.
Origin of power substations
The first substations were built in 1882 in New York, but it was only in 1930 that they began to control energy with greater precision, allowing greater flexibility in network management, with the use of transformers and other devices.
Over time and with the considerable increase in demand, substations evolved and began to adopt more advanced technologies, which allow for greater reliability in supply.
How a power substation works
A substation begins to operate with the arrival of high-voltage electrical energy from transmission lines. At the center of the substation are transformers, which regulate the voltage of the electrical energy to appropriate levels. When the energy arrives at the substation, these transformers reduce it from high voltage to medium or low voltage, suitable for local distribution. This transformation is essential, since high voltage, used for efficient transmission over long distances, is not safe for direct use in homes and businesses.
In addition to transformers, substations use other auxiliary equipment such as circuit breakers, disconnectors and protection relays. These elements provide the system with safety and reliability, allowing for remote and automated power control. Circuit breakers, for example, can interrupt the flow of power in the event of faults or overloads. Protection relays constantly monitor the system to detect problems.
Another essential piece of equipment is the busbars, which distribute the transformed energy to different distribution lines. These busbars connect the various components of the substation and direct the energy to different destinations efficiently and safely. Finally, the medium or low voltage electrical energy is sent to distribution lines that supply electricity to end consumers, completing the transmission cycle.
Power substations act as conversion and control points that allow electrical energy to be distributed safely and effectively, meeting residential, commercial and industrial needs.
Types of power substations
Power substations can be classified in several ways, depending on their location, configuration and purpose. This variety ensures that the specific needs of different contexts and applications are met efficiently and safely.
In terms of function in the electrical system:
Transformer: converts the supply voltage to a different level. It can be a step-up or step-down.
Distribution: Lowers the voltage at the primary distribution level.
Switching substation: Its purpose is to interconnect supply circuits under the same voltage.
In terms of location or installation:
Outdoor (or open-air): They are built in large open-air locations and require the use of equipment and machines suitable for operation in adverse weather conditions (rain, wind, pollution, etc.).
Indoor (or sheltered): They are hidden in masonry or metal structures and are not visible to residents.
Aerial: Commonly located on distribution poles. They may belong to the distributor or customer.
Mobile: Can be transported from one place to another. They are usually used in natural disasters or during the construction of new infrastructure.
Offshore: Located in the seas or oceans, their function is to supply electricity from offshore wind farms to substations installed on dry land.
Substations at Neoenergia
Neoenergia Substations Aiming to provide more energy to the areas served by Neoenergia's distribution companies, the concessionaires announced, in their respective locations, the investment plan that will be implemented between 2024 and 2028. The announced resources include expansion, modernization and reinforcement of the regions' electrical system.
The construction of new substations represents one of the planned initiatives. In Pernambuco alone, 13 projects will be delivered. In May, the company inaugurated the first fully sheltered substation in the state, where all components are located inside the building. In total, more than R$50 million was invested in the new substation, considered one of the most technologically advanced in Brazil.
In Bahia, the investment plan, launched by Neoenergia Coelba, foresees the construction or expansion of 71 substations.
In Rio Grande do Norte, four new substations will be built in Extremoz, Natal, São Gonçalo do Amarante and Upanema. Another 22, distributed throughout the state, will undergo modernization by 2027.
The new projects will ensure greater continuity and reliability of energy for residential customers and various sectors of the economy that make up the strength and diversity of local production: agribusiness, industry, commerce, services and tourism.