Only power plants located outside cities will be allowed to use mazut, if necessary in winter, the head of the Thermal Power Plants Holding Company’s Fuel Planning Office said.
Emphasizing that the priority of all power stations in Iran is to use natural gas, Sanaz Jafarzadeh added that in the winter, among the 18 steam power plants across the country, 14 are located outside the cities and could use mazut in emergency, Energy Today website quoted her as saying.
“Last year, mazut comprised less than 8% of the fuel used by power plants,” she said, noting that the liquid fuel has not been used in the plants situated inside Isfahan and Tehran for more than 10 years.
Mazut is a heavy, low quality fuel oil used as an alternative to run thermal power plants and factories.
With the onset of winter and higher home gas consumption, gas supply to power plants may be disrupted as priority shifts to households, which forces power plants to use liquid fuel.
The main reason for using liquid fuel in power stations is higher demand from households and industries, and if they reduce consumption there will be no need for power plants to burn liquid fuel for electricity generation. But as there is an annual growth of 6% in gas consumption in the household sector and 5% in the industrial sector, there is normally inadequate gas for all power plants during the cold season and a number of them are obliged to use mazut.
The National Iranian Oil Products Distribution Company has taken measures to supply them with sufficient liquid fuel so that they can continue their operation.
However, over the years, the use of diesel and mazut in winter, along with temperature inversion, has had a serious negative impact on air pollution.
Mazut is not suitable for power plants because it doubles maintenance costs, increases water consumption and decreases output.
Most thermal power plants run on natural gas, as liquefied fuels have long-term adverse effects. The use of diesel and mazut in power plants and other industries increases greenhouse gas emissions.
As more liquid fuel is burnt, higher volumes of toxic fumes are released into the atmosphere, making a bad pollution worse.
When power plants do not receive adequate gas, they need to either reduce output or burn liquid fuel to avoid outages in regions under their electricity coverage.
Natural gas comprises more than 83% of fuel for power plants in Iran. This is while the figure is 23% globally. There is also a 4% annual growth in gas consumption in the power plants.
