Cape Town - The government has appointed Zola Tsotsi as chairperson of national electricity supplier Eskom, the cabinet spokesperson Jimmy Manyi said on Thursday. Tsotsi replaces Mpho Makwana, who took over after the resignation of Bobby Godsell amid a dispute between the utility's board and former CEO Jacob Maroga.Manyi also said that Zoli Kunene had been appointed as chairperson of state arms manufacturer Denel. Manyi said the appointments were just part of the normal terms of board members and that the names of other new appointments at both state-owned companies would be made available later on Thursday. Business Day reported on Thursday that Transnet chairperson Mafika Mkwanazi would be moved to Eskom's board as an ordinary member.Mkwanazi, a former Transnet CEO, also served as acting CEO of the parastatal soon after his appointment as chairperson late last year.The changes are part of a bid by Public Enterprises Minister Malusi Gigaba to gain greater oversight over SA's most powerful parastatals, Business Day said.Eskom, which supplies 95% of South Africa's power, is investing R460bn to build new power plants and avoid any repeat of a crisis which forced mines and smelters to shut for days in early 2008 and cost South Africa billions in lost output.Manyi said the move to replace Makwana was not a reflection on his work, but rather part of the government’s bigger strategy to change the way state-owned companies are run. "It was done within the broad principles of renewing the board, bringing new thinking and new strategies in," Manyi said. Foreign investors have been closely watching the leadership battles at Eskom, eager to know if the company would be able to supply them with enough electricity to run their operations and to power their future expansions. Eskom has said that power supply in South Africa will be tight over the next few years until the first of its new power plants come on stream. Makwana, who has been part of the Eskom board since 2002, could not be reached for comment.Manyi said the government was also looking at restructuring the board of state-owned freight logistics Transnet, which is responsible for transporting coal and iron ore from mines to export terminals at the coast."There is a possibility that vacancies will be filled at the Transnet annual general meeting later this month and new blood introduced," he said.