Not so - check out the CSIR modelling work, including as set out in the extensive submission to the IRP process, available on CSIR website.
No need to resort to any kind of "Ponzit scheme" to support continuous manufacturing of RE technologies in SA, given the existing generation capacity to be replaced - will require up to two decades - plus additional capacity, inter alia for electrification of transport.
It is true that lifetime of RE infrastructure (generally 20 to 25 years for PV and wind, though longer for latest big off-shore turbines) is shorter than that proposed for fossil-fired power (50 to 60 years - with extensive maintenance), so is a significant factor. 
However, why invoke Ponzi specifically for renewable energy technologies? Do you imagine current levels of coal mining jobs in SA could or should be sustained indefinitely? 
Capitalist perpetual "growth" paradigm is analogous to P-scheme.
Holistic analysis shows RE more labour-intensive than concentrated energy use.