The state-owned company said it will cut 2,000 megawatts from the grid from Sunday to Tuesday after losing 10 generating units at some of its key power stations. Eskom said it’s bringing back rolling blackouts due to steam leaks at its Matla plant, while generation has also been affected at the Medupi, Kusile and Dhuva plants.

The disruptions are being investigated, Eskom said in a statement.

The debt-laden firm supplies about 95% of South Africa’s electricity needs but it’s been struggling to meet demand. Its 464 billion rand ($33 billion) of debt has added to the government’s challenges in attracting new investment to reignite economic growth in Africa’s most industrialized economy.