In Iran, most households rely on natural gas for their heating and hot water. But amid a cold snap and gas shortages, the population has been paralysed by sub-zero temperatures in many regions around the country. These gas shortages have not only led to widespread power cuts, but also severe air pollution from burning low-grade heavy fuel oil, known as mazut, to make up the difference. Despite denials from authorities, the FRANCE 24 Observers team found evidence that this fuel oil is partially responsible for the “unbreathable” air in some Iranian cities.
The lack of natural gas for power plants in Iran has another side effect beyond the cold and darkness across Iran. It has polluted the air with toxic elements. Faced with massive shortages, Iranian authorities are running the engines in the power plants to generate as much electricity as possible by burning "mazut", a polluting, cheap and low-grade heavy fuel oil.
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However, many Iranian officials have vehemently denied burning mazut. Dariush Gollizadeh, one of the deputies of the Department of Environment, said on October 9, 2022, "We do not plan to burn mazut in the power plants this year." And Parviz Sarvari, a member of Tehran City Council, said on December 16, 2022, "The power plants are not burning mazut in Tehran province".
‘Almost all power plants seem to be burning only mazut’
Termeh (not her real name) is an environmental expert in Tehran. She explains that the smoke that makes the air in Iranian cities "unbreathable" comes in part from the power plants that burn mazut, despite authorities’ denial.
The authorities deny it, but peak air pollution levels in southern Tehran and many other cities near power plants show that mazut is being burned there. In recent years, some power plants sometimes burned mazut when they did not have enough gas, but this year almost all power plants seem to be burning only mazut without interruption. The poor air quality this year is another indication of this.
The higher PM2.5 and PM10 levels in the air can have no other cause than the burning of mazut [Editor’s note: PM2.5 and PM10 are air pollutants that can endanger human health when present at high levels in the air. The tiny particles reduce visibility and make the air appear cloudy when levels are elevated]. The last day of clean air quality in Tehran was March 28, 2022. According to a study by Tehran University, at least 40,000 Iranians die each year as a result of PM2.5 pollution.
Contrary to the authorities' claims, FRANCE 24's Observers team was able to find evidence of the massive use of mazut in Iran's numerous power plants, as Termeh and other Iranian environmentalists suspected, based on satellite images and data.
Mazut is known to create dense white smoke when it burns, while the vaporisation that occurs when natural gas is burned appears almost invisible.
The difference is clear when comparing satellite images of Iran's power plant vents in January 2023 – when they were accused of burning mazut – and in the summer of 2022.
In the summer of 2022, no traces of white smoke can be seen above the power plant's chimneys, but in January 2023, dense white smoke is visible in satellite imagery.
‘This is the result of decades of mismanagement in all sectors of this country’
Termeh continued:
"The burning of mazut in this large of a quantity has a significant impact on the environment. When mazut is burnt, the power plants release fine particulate matters that are very dangerous to all living things.
Mazut contains significant amounts of sulphur and releases toxic sulphur dioxide into the air when burnt. These toxic chemicals aren't only dangerous to humans, animals and plants, but also cause acid rain. And unfortunately we don't know how big the problem really is, because there are no comprehensive studies on this for the whole of Iran. We have only some random measurements of pollution from the burning of mazut. According to one study, for example, the concentration of sulphur dioxide in the air in Isfahan reaches 1200 ppm within 24 hours when the power plant in Isfahan burns mazut, while the norm is 50 ppm."
The FRANCE 24 Observers team also looked at data from satellite detectors capable of measuring sulphur dioxide levels in the air. We compared the presence of sulphur dioxide over cities in Iran in the summer of 2022 and January 2023.
The thick layer of air pollution over Tehran and many other cities is making people sick. Walking on the streets is difficult, any physical activity is unbearable, coughing, headaches and nausea are just some of the short-term effects. Cancer and many other long-term and more serious health problems are also inevitable. And this is the result of decades of mismanagement in all sectors of this country, which cannot be reversed by some limited changes.
To solve the problem of air pollution in Iran requires a new approach to energy production, a move towards clean energy sources, and this change of course requires opening up to the outside world, foreign investment and foreign technology. This will not happen in Iran unless there is political change.
‘The gas and energy shortages will not only continue, but will worsen over time’
Economic journalist Reza Gheibi explains the lack of gas production in Iran:
Iranian households consume more than 700 million cubic metres of natural gas per day, while production is 850 million cubic metres. This means that power plants and many other industries that consume gas are without power. Production in many factories is at a standstill because they have no gas, or they burn mazut.
When factories stop working, there are fewer products on the market, and that means prices will continue to rise. The horizon is also gloomier. Since, on the one hand, there is no money to maintain and modernise the systems and, on the other hand, consumption is increasing, the gas and energy shortages will not only continue, but will worsen over time. To change this situation, Iran needs more than 80 billion euros, according to estimates by Iranian officials.
