Tavanir Improving Efficiency of Power Distribution Systems

EghtesadOnline: Approximately 45% of the domestic electricity distribution network has been renovated, deputy for power distribution affairs at Iran's Power Generation, Distribution and Transmission Company (Tavanir) said.

News ID: ۷۵۰۸۵۰

01 September 2020

"Work included installing aerial bundled conductors instead of worn-out uninsulated cables," Ghulamali Rakhshani-Mehr said, noting that 50% of the grid will be renovated before the current fiscal year is out in March, the Mehr News Agency reported.

According to the official, the grid renovation and improvement cost $250 million.

“For every 1% of distribution network improvement, 3,000 kilometers of aerial bundled conductors were used.”

Replacing and improving the ageing network, preserving the environment, reducing power waste, curbing electricity theft and increasing safety of the power infrastructure during natural disasters are the main goals.

Length of the national power distribution network stretches over 800,000 kilometers, of which 250,000 km is used for underdeveloped rural communities. Iran’s total urban population (60 million plus) is linked to the national grid.

An estimated 21 million people live in rural areas in Iran and less than 100,000 do not have electricity.

Advantage of ABC Lines

Aerial bundled conductors (ABC) are overhead power lines using several insulated phase conductors bundled tightly together, usually with a bare neutral conductor.

This contrasts with the traditional practice of using uninsulated conductors separated by air gaps. The variation of bundled conductors utilizes the same principles as overhead power lines, except that they are closer together to the point of touching but each conductor is surrounded by an insulating layer.

The main objections to the traditional design are that the multiple conductors are considered unappealing, and external forces (such as high winds) can cause them to touch and short circuit. The resultant sparks have been a cause of bushfires in drier climates.

This is a potentially dangerous fault condition. With ABC, a simultaneous disconnection of all conductors is more likely.

In moister climate, tree growth is a significant problem for overhead power lines. Aerial bundled cables will not arc over if touched by tree branches. Although persistent rubbing is still a problem, tree-trimming costs can be reduced.

Implementing power transmission/distribution substation projects, and laying aerial and ground transmission cables are among Tavanir’s duties.