No blackouts are scheduled for Tuesday, Eskom said.

"The power grid is stable so far, there are no plans to loadshed. However, we expect power to be constrained later in the afternoon as demand for electricity rises," said spokesperson Khulu Phasiwe.

In recent months, Eskom has battled to keep the lights on since the collapse of one of its coal storage silos, diesel shortages, and maintenance issues.

Because of these constraints, Eskom says it has been forced to explore options for further review of tariff increases for the 2015/16 financial year.

The National Energy Regulator of South Africa has confirmed Eskom is formalising an application to reopen the multi-year price determination, allowing for a further increase in electricity tariffs.

Two weeks ago, Eskom chief executive Tshediso Matona, finance director Tsholofelo Molefe, group capital executive Dan Morokane, and commercial and technology executive Matshela Koko were asked to step aside as the power utility embarked on a fact-finding inquiry.