The move signals the state-owned electricity utility's determination to expand the use of renewable energy sources in its generation mix, which has historically mainly focused on its fleet of coal-fired power plants that contribute significantly to air pollution and climate change.
In a statement on Friday, Eskom said Mnisi will focus on delivering an Eskom renewable energy business "that will become a significant player in this segment, focusing on work already in progress for an executable initial pipeline of at least 2GW of clean energy projects by 2026".
"He will also lead the advancement of Eskom's pipeline of more than 20GW of clean energy projects to diversify its energy mix as part of the emissions reduction strategy," it said.
Mnisi was previously chief strategy officer at resources group Exxaro. He has also worked for Anglo American and holds a bachelors degree in industrial engineering from the University of Johannesburg, a BSc honours in applied science from the University of Pretoria and an MBA from the Gordon Institute of Business Science.
At the same time, Eskom said it has appointed Candice Hartley as chief people officer.