An analysis of the costs of the coal-fired power station in Mpumalanga show the construction bill is a drop in the ocean compared with wider costs over the plant's 50-year lifespan.
Pretoria University economics doctoral student Nonophile Nkambule said the costs included the plant's effect on biodiversity, air pollution, greenhouse gas output, damage to roads, noise and water quality.
He put its total costs at between R1.449-trillion and R3.279-trillion, equivalent to between 91c and 205c per unit of electricity produced, with water the biggest-ticket item at around two-thirds of the total.
Even a conservative estimate of the lifecycle burdens of Kusile, near Witbank, "doubles to quadruples the price of electricity, making renewable energy sources such as wind and solar attractive alternatives", said Nkambule.
He said about 77% of South Africa's electricity is derived from coal.
On August 30 Eskom said it had brought Unit 1 of the Kusile power station into production, four years behind schedule.