An underground 132/20 kilovolt gas-insulated substation was inaugurated in Mashhad, Khorosan Razavi Province, at the weekend.
“The substation is built over 1,100 square meters and is 16 meters below the surface. It cost $2 million,” head of Khorasan Regional Electricity Company Reza Riahi was quoted by IRNA.
A GIS is a high voltage substation in which the major structure is sealed with sulfur hexafluoride gas as the insulating medium. It is mostly used where real estate is expensive or not available. The technology originated in Japan where there was a substantial need to develop technology to make substations as compact as possible.
“The project will help increase reliability of power grids in Mashhad and reduce electricity wastage,” Riahi said.
In a GIS, the active parts including transformers and feeders are protected from corrosion emanating from exposure to atmospheric air, moisture, contamination and sand.
"Conventional substations are built on 10,000 square meters of land, whereas a GIS needs 1,000 square meters,” he added.
Gas insulated substations offer other advantages in addition to the reduced space requirement. As a substation is enclosed in a building, a GIS is less sensitive to pollution, as well as salt, sand or large amounts of snow. Although the initial cost of putting up a GIS is higher than building an air-insulated substation, operation and maintenance costs of a GIS is less.
In addition to providing household and industrial consumers, Khorasan Razavi Province annually exports 800 MW of surplus electricity to Afghanistan.
“Iran has power contracts with neighboring countries,” the official noted.
Regional Deals
The Trade Promotion Organization of Iran says the government generated $4.1 billion from electricity exports between 2013-18. It exported over 42 million kilowatt-hours of electricity to neighbors.
Besides exporting to Afghanistan and Pakistan, Iran trades electricity with four neighbors on its northwestern and western borders, namely Azerbaijan Republic, Turkey, Armenia and Iraq.
As the largest exporter of electricity in the Middle East, Iran is central power distributor in the region, with an installed power generating capacity of around 82,000 MW.
The power industry is present in over 40 international markets as exporter of equipment and technical services under engineering, procurement and construction contracts.
Iranian contractors are present in Iraq and Syria as the two biggest potential markets in need of power infrastructure due to the protracted military conflicts in the two Arab countries and rapidly rising demand.
Construction of a combined-cycle power plant in Torbat-e Heydarieh county, Khorasan Razavi Province, started on Thursday.
The plant will have two thermal units each with 176 MW capacity and a 170 MW steam unit.
Built on 50 hectares, the plant is expected to come on stream by 2022. A joint venture of state and private firms is building the $215 million plant.
