As Iran’s main energy artery, the national gas transmission network is responsible for delivering hundreds of millions of cubic meters of gas daily to residential, industrial, power generation, and export sectors—a responsibility that continues uninterrupted despite seasonal shifts, higher demand, or major maintenance operations.

The stability of this 40,000-kilometer-long network is the result of precise planning, continuous development, preventive maintenance, advanced technologies such as intelligent pigging, and increasing reliance on domestic technical expertise. The importance of these efforts doubles when considering that the first half of the year is not merely a low-demand period but a “winter preparation phase”—a critical stage ensuring the network’s capacity, resilience, and flexibility to guarantee a secure gas supply for the nation.

In an interview with Shana, Iran’s oil and energy news agency, Peyman Khazraei, managing director of the Iranian Gas Transmission Company, discussed the backbone of the country’s energy flow—where even during the hottest summer days, more than 700 million cubic meters of gas are transmitted daily without interruption. Below are highlights from the conversation, including transmission statistics, network stability, and the intensive pipeline and compressor station readiness operations for the coming winter.

 How much gas was transmitted during the first half of this year?

The total volume of sour and sweet gas transmitted from the beginning of 1404to the end of September reached about 145 billion cubic meters. Gas consumption patterns change throughout the year; currently, before the onset of the cold season, roughly 720 million cubic meters of gas are transmitted daily. Last month, despite high temperatures, the figure was around 703 million cubic meters. This steady trend shows that seasonal variations have little impact on the company’s performance. Minor fluctuations are mainly due to periodic overhauls, which are never carried out during winter.

 What measures were taken in the first half of the year to prepare for winter?

The first half of the year is regarded as the “winter preparation phase.” During this time, a series of extensive and heavy operations take place in two main areas.

The first includes maintenance programs for transmission lines and compressor stations. After detailed inspections and evaluations, repairs are made to ensure pipeline integrity and pressure resistance. One of the main tools used in this process is the intelligent pig, which detects flaws inside pipelines and guides the repair work. Given the network’s vast scale and technical complexity, these operations constitute a major part of the company’s first-half activities.

The second area involves the overhaul of turbines and compressor equipment, managed under the company’s Maintenance Division. These processes are conducted through a comprehensive, automated maintenance management system that uses advanced software unique in its scope across Iran. This platform, developed and refined over recent years, has optimized and digitized the network’s maintenance structure—forming the first phase of winter preparedness.

In addition to maintenance, other initiatives were taken to increase capacity, stability, and resilience, including constructing new transmission lines and strengthening key sections for better gas distribution.

Currently, the network operates 40,260 kilometers of pipelines divided into 11 operational regions, supported by 95 active compressor stations containing 351 compressor units. Operations and maintenance are carried out through 62 field centers across the country.

 How do compressor station overhauls differ from pipeline maintenance?

Overhauls at compressor stations are even more critical than pipeline repairs, though both are essential. Pipeline maintenance helps preserve capacity and extend service life through coating repairs, structural reinforcement, and cathodic protection systems that prevent corrosion. The condition of pipelines is constantly monitored, much like routine health checks for human systems.

This year, approximately 600 defects were repaired across national trunklines—mainly on the third, fourth, and eighth pipelines. Another 500 locations on export lines to northern regions and Tehran pipelines were inspected and repaired. In total, 1,100 points underwent review and restoration. Additionally, 902 kilometers of pigging operations were completed, which will inform future maintenance schedules.

For compressor facilities, the overhaul of 26 main gas compressors has been completed, and work on 30 turbines is ongoing with strong progress relative to workload. These measures ensure the transmission network has sufficient capacity and resilience to supply gas reliably—especially to the northern half of the country—during winter. Without such work, safe and stable gas transmission during peak demand periods would not be possible.

 Why are compressor relocations carried out?

To strengthen reliability in the northern corridor, three compressors from the Farouj station were relocated to Ramsar, replacing 7.5-million-cubic-meter units. This increased the station’s capacity to 22.5 million cubic meters per day. Remarkably, this task was completed in less than two months without contractors—entirely through in-house technical expertise.

At the same time, close monitoring and progress tracking of turbine repairs were conducted, with multiple contingency scenarios based on contractor delivery timelines. For example, at Kheirgoo 8, one of the main transmission facilities, three turbines are nearing their service limit. Since no spare units are available, a plan was devised to relocate one turbine from Bijar to Kheirgoo to prevent operational disruption.

 What is the plan for network expansion and increased transmission capacity?

The National Iranian Gas Company (NIGC) plans to construct 948 kilometers of new pipelines by the end of 1404, of which 255 kilometers have already been completed and commissioned. Some of the remaining sections will come online in the second half of the year, including 395 kilometers of the Ninth National Pipeline, which is being completed in stages. This continuous expansion ensures that the transmission network grows steadily, with all remaining sections scheduled for completion by year’s end.

According to the development plan, the network’s overall capacity will rise by the end of 2025 as new pipelines and compressor stations are integrated, enabling greater gas flow during peak seasons—especially in winter.

The national network consists of three main corridors:

 Western corridor – including the 4th, 6th, 8th, and 9th national pipelines, stretching from the south toward western and northern regions.

 Central corridor – comprising the 2nd, 3rd, and 10th pipelines running through Shiraz, Isfahan, and central Iran.

 Eastern corridor – represented by the 7th pipeline, extending from Zahedan northward.

These corridors are interconnected through linking lines, forming an integrated transmission grid that enables operational flexibility to direct gas to high-demand northern regions.

This year, four compressor stations were slated for commissioning. So far, Dehshir and Borazjan have begun operations, with Ardestan and Lamerd to follow soon. These projects reduce the need for complex operational maneuvers, delivering gas more efficiently to consumers. However, despite these advances, energy imbalance remains a challenge, and full equilibrium between production and consumption has yet to be achieved.

In 1403, the volume of sweet gas transmitted reached 281 billion cubic meters, reflecting the system’s expanded capacity and the alignment of gas production and transmission with rising demand from households, industries, and power plants.

“Our motto is ‘Gas is the engine of development,’” Khazraei said. “By ensuring its supply, we help industries flourish—but unfortunately, some consumers still do not use gas efficiently.”

Interview by

Mojgan Faraji