The Centre for Environmental Rights has applied to be a friend of the court in the case in which the City of Cape Town is seeking to be allowed to procure its own renewable energy without needing permission from the national energy minister.

The matter is being heard in the high court in Pretoria.

The organisation said on Tuesday that municipalities, which accounted for 40% of South African electricity use, were key to cleaning the country’s deadly air and must be allowed to do so by procuring clean electricity.

The centre said coal pollution had killed thousands of South Africans and left many more debilitated with illness. It said coal emissions had driven the climate crisis with catastrophic impacts on South Africa, yet the department of energy had failed to act with urgency to secure a clean energy transition.

The centre said through its application, it wanted to help the court in understanding the important role that local governments must play in protecting human health and the environment by facilitating the transition from harmful fossil fuel-based electricity capacity to renewable electricity.

"All evidence shows that we urgently need to decarbonise the electricity sector to have any hope of avoiding the worst impacts of climate change.

"Municipalities seeking to procure clean and sustainable energy sources must be supported – they are fulfilling their constitutional obligations to protect human health and the environment, and to mitigate climate change," the centre's attorney, Nicole Loser, said in a statement.

In its application, the city said in November 2015, it applied to the Minister of Energy for a determination that would allow it to purchase solar and wind power from an Independent Power Producer (IPP), which would establish new generation capacity to supply the city.

“The Minister has however to date failed  to determine the City’s application," the City of Cape Town’s director of enterprise and investment, Lance Greyling, said in an affidavit deposed to the court July 2017.

Greyling said the city sought legal advice and was informed that Section 34 of the Electricity Regulation Act allowed the minister to determine the need for new generation capacity and to take the initiative for its procurement.

The city said it was advised that the section did not preclude anybody else from establishing and operating new generation capacity as long as they were duly licensed to do so by the National Energy Regulator of SA (Nersa).

“The City’s problem, however, is that Nersa believes that an IPP may not establish and operate  new generation capacity without a ministerial determination in terms of section 34,” Greyling said

He said Nersa would accordingly not licence an IPP to establish and  operate new generation capacity without such determination.

Nersa is opposing the application.

In its answering affidavit, Nersa said municipalities were not conferred any powers, either by the constitution or by law, to plan and determine when and where new power generation should be permitted, or to authorise its rollout.

"Contrary to the city’s claim, municipalities have no ‘right’ to determine, independently of national policy and plans, where to source their electricity. It is not practically possible to permit them to do so," Nersa’s  full time regulator responsible for electricity, Muzuvukile Mkhize, said in his answering affidavit filed with the court in March last year.

The application by the city will be heard later this year.