At a joint press conference with South African president Jacob Zuma, Hollande announced the agreement between French energy firm GDF Suez and South Africa for “a thermal power plant to the tune of 1.5 billion euros, and also for a solar plant."
South Africa is currently unable to meet demand for energy and in 2008 there were rolling power cuts.
The country has now embarked on a multi-billion-dollar building spree to set up new power plants that would double electricity supplies over the next two decades.
Heavily reliant for decades on coal, it is now considering other energy sources including nuclear power and shale gas.
It plans to add more than 50,000 megawatts of electricity to the grid and hopes to generate at least 3,725 megawatts in green energy, in its bid to lower the over-reliance on coal.
Hollande also announced the conclusion of a deal worth more than 4 billion euros by Alstom to overhaul South Africa's passenger rail service, PRASA.
Under the deal, which was first announced in December last year, Alstom would build 600 trains and 3,600 wagons over a 10-year period from 2015 to 2025.
The deal, which Hollande described as "the largest in recent years" and an example of an "excellent partnership" between the two countries, would create several thousand jobs.
Part of the accord is that most of the parts used in the work will originate in South Africa.
It is the first phase of a much bigger, more than ten billion dollar project to revamp South Africa's Metrorail system, including the building of 7,224 commuter trains for Gauteng province which includes Johannesburg and Pretoria and also for Durban, the Western Cape and Eastern Cape.
About 90 percent of the current rolling stock is said to date back to the late 1950s.