Saeid Tavakoli said the share can rise to as much as 80% during winter consumption patterns.

Speaking Thursday on the state television program “On the News Line,” Tavakoli said about 850 million cubic meters of gas is typically injected into the national grid during the cold season. Of that amount, 435 million cubic meters is considered baseline consumption for the residential, commercial and small industrial sectors. As demand in those sectors increases, restrictions must be imposed on other consumers, most of which are energy-intensive sectors.

He said consumption in the residential, commercial and small industrial sectors reached 625 million cubic meters on Wednesday and is expected to rise to about 650 million cubic meters by Friday due to the persistence and arrival of cold air masses, particularly in southern regions, the central plateau and the country’s northeast. According to weather forecasts, temperatures are also expected to decline next week and the following week, which typically leads households to adjust consumption based on colder conditions.

Winter Consumption Pattern

The deputy oil minister said 72% of gas consumed Wednesday was used by the residential, commercial and small industrial sectors, a figure that can reach 80% in winter. The remaining 20% of gas in the network is consumed by other users, including major industries, power plants and operational uses.

When the share of household and similar consumers reaches 80%, other consumers are required to switch to alternative fuels, he said.

Tavakoli said the Oil Ministry has defined an integrated fuel basket for power plants and industries that includes natural gas, diesel and fuel oil. As residential and commercial demand rises during winter, power plants naturally shift to liquid fuels.

He added that gas consumption has increased by about 100 million cubic meters over the past four days. Since early November, continuous monitoring has been carried out, including issuing warnings and cutting gas supplies to government offices that fail to comply with consumption rules. Some subsidiaries of the Oil Ministry have also faced gas cuts. Under regulations, government bodies are required to reduce consumption by 20%.

Gas Tariffs Based on 1,300 Climate Zones

Tavakoli said gas tariffs were previously calculated based on five climate zones, but the system has now been expanded to about 1,300 climate zones to more accurately and fairly reflect average consumption in each city.

He said the number of tariff steps has been reduced from 12 nonstandard tiers to four standard tiers, meaning only about 2% of high-consumption subscribers face higher charges.

Under the system, offices that follow consumption patterns fall into the third tier. Subscribers in the first and second tiers are considered low consumers, the third tier poor consumers and the fourth tier very poor consumers. About 2% of subscribers fall into the fourth tier, but they account for roughly 6% of total gas consumption, particularly during the cold season.

Tavakoli said the comfort temperature range is between 18 and 21 degrees Celsius. A one-degree Celsius reduction in indoor temperatures during peak winter would save about 25 million cubic meters of gas — roughly equivalent to the output of one phase of the South Pars gas field.

Energy Efficiency Measures

He said implementing energy-saving measures in buildings could reduce heating energy consumption by about 35%, adding that the temperature of boilers and water heaters should be set between 50 and 60 degrees Celsius.

Tavakoli cited a program to replace existing gas heaters with high-efficiency models as another key measure to cut household and commercial gas consumption. The plan, aligned with an Economic Council resolution, aims to optimize gas use nationwide.

This year, contracts have been signed for about 1.75 million heaters, with a target of installing 300,000 high-efficiency units by the end of the year. About 100,000 such heaters have already been distributed, with the total expected to reach 300,000 by year’s end and 4.1 million within the next two years.

High-efficiency gas heaters, with efficiencies above 85%, are replacing older models and have proven effective in reducing energy consumption, he said.

Tavakoli said there were no household gas outages nationwide last year. Since the start of this year, all necessary measures related to energy-producing facilities have been implemented. Any recent household gas disruptions were due to technical issues, he said, adding that cutting gas to households is not policy, though higher-tier bills are intended to discourage excessive consumption.