The RSA power system became constrained again in the first quarter of 2019, with Eskom needing to loadshed to stage 4 at times. Causes of loadshedding have been cited as high unplanned plant failures on the thermal coal fleet, the loss of the Cahora Bassa import from Mozambique followed by intensive use of diesel (at OCGTs) and water (at pumped storage schemes) which eventually depleted.
Reference:
Wright J.G. and Calitz, J.R. 2019. Brief analysis of variable renewable energy contribution during loadshedding (Q1-2019).
Wright, J. G., & Calitz, J. R. (2019). Brief analysis of variable renewable energy contribution during loadshedding (Q1-2019). CSIR. http://hdl.handle.net/10204/11017
Wright, Jarrad G, and Joanne R Calitz. "Brief analysis of variable renewable energy contribution during loadshedding (Q1-2019)." (2019): http://hdl.handle.net/10204/11017
Wright JG, Calitz JR, Brief analysis of variable renewable energy contribution during loadshedding (Q1-2019); CSIR; 2019. http://hdl.handle.net/10204/11017 .