The facility which is based in De Aar, is expected to produce more than 175 megawatts of power.
Energy Minister Tina Joemat-Petterssen is expected to attend the official switch on of the Solar Capital Power Plant this morning.
It's the largest in Africa and will produce power that's equivalent to providing electricity to at least 75,000 homes a year.
Power utility Eskom has also built a substation on the premises which will help store the electricity.
The Northern Cape, which is one of the most sun-drenched provinces, has about four solar power plants in the region.
