Which system is responsible for delivering electricity from local transformers to endusers?

Secondary Distribution System

Definition: The secondary distribution system is the part of the electric power distribution network that delivers electricity from local transformers to the end-users or consumers. It is the final stage of the electricity supply chain, ensuring that power reaches homes, businesses, and other establishments at the appropriate voltage level for consumption.

Working Principle: In a secondary distribution system, electricity is received from the primary distribution system through a step-down transformer, which reduces the voltage to a level suitable for end-use (typically 230V for single-phase or 400V for three-phase systems). This reduced voltage power is then distributed to consumers through a network of distribution lines, poles, and cables.

The system comprises distribution boards, feeders, service mains, and consumer connections. The feeders carry electricity from the transformer to distribution boards, from where it is further distributed to individual consumers via service mains. The key objective of the secondary distribution system is to ensure a reliable and efficient supply of electricity to consumers.

Advantages:

• Delivers electricity at a consumer-friendly voltage level, ensuring safety and compatibility with household and commercial appliances.
• Allows for efficient distribution of power to a large number of end-users within a localized area.
• Facilitates the use of modern metering and monitoring technologies to improve energy management and billing accuracy.

Disadvantages:

• Requires extensive infrastructure, including poles, cables, and transformers, which can lead to high installation and maintenance costs.
• Vulnerable to power losses due to resistance in the distribution lines and potential faults or failures in the network.

Applications: The secondary distribution system is used in urban, suburban, and rural areas to provide electricity to residential, commercial, and industrial consumers. It is a critical component of the power distribution network, ensuring that electricity reaches the end-user efficiently and reliably.

Correct Option Analysis:

The correct option is:

Option 4: Secondary distribution system

The secondary distribution system is specifically responsible for delivering electricity from local transformers to end-users. After the primary distribution system transmits power to local substations or transformers, the secondary distribution system takes over, stepping down the voltage and distributing it to individual consumers. This system directly connects with homes, offices, and other establishments, ensuring that they receive electricity at a usable voltage level.

Additional Information

To further understand the analysis, let’s evaluate the other options:

Option 1: Generation system

The generation system is the initial stage of the electricity supply chain, where electrical energy is produced in power plants using various energy sources such as coal, natural gas, nuclear, hydro, wind, or solar energy. While the generation system is responsible for producing electricity, it is not involved in delivering power to end-users. Instead, it supplies power to the transmission system for further distribution.

Option 2: Primary distribution system

The primary distribution system is an intermediate stage between the transmission system and the secondary distribution system. It distributes electricity from substations to local transformers at medium voltage levels (usually between 11kV and 33kV). Although it plays a crucial role in the distribution network, it does not directly deliver electricity to end-users. Its primary function is to serve as a link between the transmission network and the secondary distribution system.

Option 3: Transmission system

The transmission system is responsible for transporting electricity over long distances from power plants to substations at high voltage levels (typically ranging from 110kV to 765kV). The high voltage minimizes power losses during transmission. However, the transmission system does not deliver electricity directly to end-users. Instead, it feeds electricity into the primary distribution system for further distribution.

Option 5: Not Applicable

This option is irrelevant to the question as the correct answer lies within the specified options (1 to 4). The secondary distribution system is the appropriate choice for delivering electricity from local transformers to end-users.

Conclusion:

The secondary distribution system plays a vital role in the electricity supply chain by ensuring that power reaches consumers at a usable voltage level. It is the final stage of the distribution network, connecting local transformers to individual homes, businesses, and other establishments. While other systems such as generation, transmission, and primary distribution are essential for producing and transporting electricity, they do not directly deliver power to end-users. Understanding the functions of each system helps in appreciating the complexity and efficiency of modern power distribution networks.