Overhead or Underground Cable System: Which Is Best For Your Business?

Industrial buildings and factories are known for their large power requirements and it is important to ensure that they receive the right amount of electricity. As such, when you are looking to meet the electricity requirements of your building or factory then it is important to understand the difference between overhead and underground cabling and the benefits and requirements of each.

What Is The Difference Between Overhead And Underground Cabling?

Underground and overhead cables are used to transmit electricity from a generating station to consumers. Underground cables are buried and are insulated using armouring. The cables consist of one or more conductors that are laid within insulation to isolate the conductor/s. Overhead lines, on the other hand, are simply a conductor laid using transmission towers. In underground lines, the capacitor plays a major role while in overhead the inductor is critical.

To mitigate large charges produced in high voltage cables it is advisable to minimise the cable length, as is commonly done with underground cables. This is why underground cables are preferred over overhead transmission lines for low and medium voltages and why overhead cables are preferred for high voltage.

How Are Both Constructed?

Apart from the obvious, that one is above ground and one is below, there are other differences between underground and overhead cables. 

Overhead cables are traditionally simple in configuration and are made using towers and poles and cabling. The bare wire used for the conductors on the lines tends to be steel or composite reinforced aluminium before often leading into the copper wire to connect to the customer’s premises. As the conductor is exposed to the atmosphere and a large number of external factors, there can be concerns related to safety and reliability. Everything from the salty air to heavy rain, to wind, can affect the lifespan of cables. This is often offset by the lower costs of overhead cables due to the lack of insulation required and the clear fault identification due to the visibility of the cables. 

Underground cables are quite different from overhead. The underground cables provide an uninterrupted power supply and their location tends to mitigate external factors. However, there are other areas in which underground cables differ. The cables also have armour rather than simply being the exposed wire of overhead cables. There is also significant concern related to heat build-up for underground cabling which is built into their design with the inclusion of manholes along cabling routes. It can also be harder to spot faults in underground cables as they are not visible 99% of the time.

Which Is Best For An Industrial Environment?

The decision on whether to go with overhead or underground cabling comes down to voltage. Based on cost alone, nearly all cabling would be overhead, however, this is not always the case. For lower voltages for distribution then underground cables tend to be the way to go as overhead cables tend to create large charges, this can be particularly problematic if your site is near a residential area where the overhead cables are seen to cause environmental impairment. Traditionally, for power transmitted from plants the use of overhead cables tends to be the way to go. However, for the distribution of power, most use underground cables.

Need Help With Either System? Contact Asset Power Solutions

Need help with your underground or overhead cables? Don’t stress! The team at Asset Power Solutions are here to help. With over a decade of specialised experience, our experienced electricians are a dependable partner in looking after your power supply. Contact us today for reliable and quality low, medium, and high voltage services.