Being developed by South Africa’s state-owned power utility Eskom in north of Johannesburg, the Medupi power station will feature six units.

The first unit, Unit 6, was connected to the grid in March 2015.

The power plant construction started in 2007. However, due to strikes, technical issues and cost overruns, the project completion date was rescheduled to 2019, which is now running seven years behind schedule.

South Africa President Jacob Zuma said: "Shortage of energy does not only cause enormous inconvenience, it is a serious impediment to economic growth. Today, I am here to say, there is light."

The $7.89bn project, which is expected to have an operational life of 50-years, will be the fourth-largest coal-fired plant and the largest dry-cooled power station in the world.

Eskom is planning to have 17GW of power generation capacity by 2019 which include the 4,800MW Kusile coal-powered station and the 1,332MW Ingula pumped-storage power project, reported Bloomberg earlier.

The company supplies more than 95% of power requirement in South Africa.

Meanwhile, the government is also planning to generate 9,600MW of nuclear power by 2030 in an effort to reduce its dependency on coal-fired power, reported Reuters.