Africa Energy week highlighted need to invest in power generation and renewables.
The project in Doornkloof, Pretoria, is set for completion by August 2023.
The 210 million-litre reservoir is the largest circular post-tensioned reservoir in the world.
The plant will add 100 MW to the national grid and be operational by 2024.
The roads agency said the move aims to boost the construction sector as part of government investment.
Construction works by the CME JV is expected to be completed in the last quarter of 2024.
CSI Solar will deliver the modules to two power projects in the country's North West province.
South Africa now joins eight other countries globally to produce liquid helium.
The project will generate over 325 GWh of clean energy per year, powering about 25,000 households.
The digital realty company sees sustained demand for hybrid cloud deployments and the adoption of cloud services in Africa.