EghtesadOnline: While most power plants in Iran use gas to generate electricity, Bandar Abbas Thermal Power Station is among the few still using mazut as the main feedstock and is a major source of air pollution in the capital of southern Hormozgan Province, director general of Hormozgan Provincial Directorate of Department of Environment said.
“Carbon monoxide and nitrogen oxide emissions by the plant are, respectively, four times and 2.5 times the allowable limit,” Habib Masihi Taziani was quoted as saying by Bargh News.
Efforts are underway to supply sufficient natural gas to the plant and cut mazut consumption to reduce emissions, the official added.
“The plant is waiting for laying another gas transmission pipeline.” The largest of its kind in the south, the plant supplies 60% of the province's electricity.
Initially gas-fired, the power station has a nominal capacity of 1,320 megawatts. To operate at full capacity, it needs 8 million cubic meters of natural gas per day as feedstock. It barely receives 10% of this volume.
The port city of Bandar Abbas receives gas via a pipeline from Qeshm Island off the Persian Gulf. Gas delivered via the pipeline is 2 million cubic meters per day, of which 500,000 meters is sold to the power plant, and the rest to homes, industries and CNG filling stations.
For network stability and preventing power outages, this plant has no option but to use mazut to make up for the gas deficit. “Burning every four mcm of mazut produces 10 tons of sulfur dioxide -- a toxic gas,” Masihi Taziani said.
Fuel oil contains sulfur impurities. When it burns, sulfur burns too which releases sulfur dioxide. SO2 causes breathing problems for living creatures and contributes to acid rain.
Consumption of the liquid fuel also has a negative impact on machinery as it raises the cost of repairs and causes wear and tear of parts and equipment.
Rehabilitation of plants that burn mazut needs more funds as machinery and equipment regularly exposed to the dirty liquefied fuels become less durable and need to be replaced at shorter intervals.
Total liquid fuel delivered to power plants in Iran during the last fiscal year (ended March) was 13.8 billion liters, of which about 4.3 billion liters were mazut and 9.5 billion liters diesel.
As gas consumption rises, especially among households in the cold season, using mazut becomes inevitable for electricity generation because gas supply is cut off to power stations to meet high home demand.
Hike in electricity consumption in the hot season also compel thermal plants to use liquid fuel in addition to gas for power generation to help avoid outages.
Almost 95% of thermal power plants are gas-fired and have a small share in air pollution as emissions from gas combustion are way below those from other fossil fuels like diesel and mazut.
As air pollution concerns in Iran take on more serious dimensions like in other countries, concerted efforts are being made to put an end to the use of mazut in power plants.
The government has ordered power plants and refineries to use gas instead of dirty feedstock and make use of the rising output from the South Pars Gas Field.
Iran has abundant natural gas deposits, and it is more cost-effective to use gas for power generation instead of other liquid fuels.