Difference between Transmission Line and Distribution Line

The primary distinction between the transmission and distribution line lies in the transmission line’s capacity to carry large amounts of power at high voltage, whereas a distribution power line transports power at low voltage.

Introduction

Electrical energy, generated at various types of power stations, needs to be transported from these stations, often located far from consumption points, to end users. This process involves two main stages: transmission and distribution, each utilizing distinct types of power lines.

Transmission Line Overview

Transmission lines are high voltage power lines that transport electricity from generating stations to electric substations. They include primary transmission lines, which connect generating stations to receiving stations, and secondary transmission lines, which link receiving stations to electrical substations for further distribution to end users.

Distribution Line Overview

Distribution lines are the networks that deliver electrical energy directly to consumers. Operating at lower voltages, they distribute power from substations to consumer premises, and are divided into primary and secondary distribution lines.

Key Differences

Parameter	Transmission Line	Distribution Line
Description	High voltage lines transporting energy from generation to substations.	Lines carrying electrical energy from substations to end users.
Voltage Level	Operates at high voltages (33 kV, 66 kV, and more).	Relatively lower voltages, usually 11 kV or less.
Current Capacity	Designed for large current capacity.	Lower current capacity.

Conclusion

Transmission and distribution lines form the backbone of electric power systems, linking generating plants with consumers. Despite their shared goal of electricity conveyance, their operational characteristics and physical configurations differ significantly.