Understanding Electricity Distribution — From the Substation to Our Homes
We have our devices and utilities plugged in 24/7, not even thinking of it much on a daily basis. And turning that light on when it's getting dark outside takes less than a second after we move the switch.
But while electrical power is the easiest to transmit over long distances, electricity has to travel a long way before it reaches our homes. So what journey does it make?
What is a distribution system in electricity?
From a plant station and through transmission networks, electricity reaches distribution substations. These are stations located in cities, towns and villages to redistribute power to smaller destinations, eventually leading to our homes.
A distribution system for electricity consists of a distribution substation, distribution feeders, service transformers, distributor conductors, service main conductors, protection and measurement equipment, along with other details.
On the first part of the journey, which is on its way to the substations, the voltage is quite high, 110 kV and above, to ensure fast and secure transmission. But at the distribution substations, the power travels through feeders to service transformers and distribution conductors, where the voltage lowers to the range of 2.4-33 kV.
Then, through service mains, which are basically wires we’re used to seeing outside, the power travels to neighborhoods. And this is when electricity is distributed to our homes, offices or any other buildings. It then goes through the meter to record how much power an individual household uses and to the service panel, where the system gets protected from overloads.
Lastly, wires in the walls of your house allow the power to reach switches and devices you use.
Types of power distribution systems
Electricity distribution systems can be divided into types by the current nature, construction type and connection scheme.
Current nature: alternating current (AC) or direct current (DC) distribution system
Construction type: overhead or underground distribution system
Connection scheme: radial, ring main or interconnected distribution system
Electricity distribution levels
Primary distribution implies the end part of the power path when higher voltages need to be delivered to the consumer. In most countries, voltages transmitted in primary distribution are 3.3 kV, 6.6 kV and 11 kV.
With this being said, it usually covers power distribution from the substation to large consumers, like those in industrial areas, factories and others. Sometimes, primary distribution systems feed smaller substations that carry out secondary distribution.
Secondary distribution implies that power is delivered to the end consumers in residential areas. Houses are provided with 230 V if it's a single-phase supply. In the US and some other countries, the voltage is 120 V.
Secondary distribution covers bigger, non-domestic facilities too, like small factories or commercial buildings. These are fed with 400 V by a 3-phase supply.
Choosing the right wiring for your home
If you're looking for electrical cables for any part of the power distribution system, Nassau National Cable has the supply of wires for this application. Among these, we have Medium Voltage Power Cables and Portable Cord Cables, like SOOW 600V and SJEOOW 300V. If you need consultation on what type of wiring you need, just reach out to our team for more details.