Eskom will be allowed to temporarily bypass the flue-gas desulphurisation unit, which cuts sulphur dioxide, or SO2, emissions by as much as 99%, at three units at its Kusile power station, as it conducts repairs at the plant, which has been affected by a chimney collapse. The units could be operating by November and would, if run at full capacity, generate 2,100 megawatts of electricity.

Sulphur dioxide is linked to ailments ranging from asthma to heart attacks. In 2021, the Centre for Research on Energy and Clean Air (CREA) said Eskom is the world’s biggest emitter of the pollutant.

I am “aware of the health and associated impacts of exposure to sulphur dioxide emissions, particularly on communities in close proximity to coal-fired power stations,” Barbara Creecy, the environment minister, said in a statement on Wednesday. “In light of the competing factors, I have been called on to make an extraordinarily difficult decision.”

South Africa is in the midst of its worst power crisis, with rotational blackouts imposed every day this year so far, often exceeding 10 hours per day.

The Centre for Environmental Rights (CER) has estimated that the 13-month period allowed for the exemption could lead to the premature deaths of 492 people.

The decision has spurred opposition from environmental groups including the Life After Coal Campaign, run by the CER and Earthlife Africa.

The groups are questioning whether the action “to allow Eskom to dump sulphur dioxide from unabated polluting emissions into the atmosphere would meet the requirements of the Constitution”, it said in a statement, adding that affected communities have not been given enough time to make representations against the decision.

The temporary respite will result in Eskom increasing emissions of SO2 eightfold, to 80,000 tonnes at Kusile alone, said Lauri Myllyvirta, lead analyst at CREA.

Life After Coal cited studies saying that Eskom’s pollution is already killing more than 2,200 people a year. Eskom has, in court documents, said that figure is exaggerated but conceded that 320 people die prematurely annually.

The pollution’s roots lie in government inaction over many years, Myllyvirta said.

“The failure of the government to require Eskom to control its SO2 emissions and to refurbish its plants is time and time again confronting the country with a choice between extremely dirty electricity and rolling blackouts,” he said.