If SA had 5,000MW of additional renewable-energy capacity, load-shedding could have been almost completely avoided in 2021. Instead, 2021 overtook 2020 as the most intensive year of load-shedding to date.
A new report released on Monday by specialist economics advisory group Meridian Economics investigates how, using Eskom’s hourly data from 2021, having more renewable-energy capacity on the system would have affected load-shedding in 2021.
Meridian Economics has been conducting influential research and policy analysis on SA’s energy landscape for about 15 years and on aspects related to the transition from a high- to a low-carbon economy for the last five years. In 2017 the consultancy released a groundbreaking report that detailed how Eskom could save itself billions and shield consumers from excessive energy costs by curtailing the construction of Kusile and retiring several of its old coal-fired power stations early.
A 96.5% reduction in load-shedding
Analysis that used two separate modelling platforms showed that 5,000MW of additional renewables, which could have feasibly been installed by 2021 had there been no interruption in the rollout of the Renewable Energy Independent Power Producer Procurement Programme (REIPPPP) in 2016, would have resulted in a 96.5% reduction in load-shedding.
In addition, this amount of additional renewable capacity would have resulted in a reduction in coal-generated energy of about 10TWh. This is the equivalent annual production from 2,160MW of coal capacity — the entire installed capacity of Kusile in 2021.
“This would have provided a large increase in the ‘space’ for significantly more maintenance to have been done on the coal fleet, thus increasing the energy-availability factor and likely further reducing the need for load-shedding,” the report said.
In the absence of further urgent and drastic interventions, load-shedding is likely to increase substantially in the coming years.
— Denene Erasmus, journalist
In its annual publication of power generation statistics for SA that was published last week, the Council for Scientific & Industrial Research (CSIR) said the Eskom fleet energy availability factor (EAF), a measure of the amount of electricity generated compared with the total installed generation capacity, continued its declining trend in 2021 with an average EAF of 61.8% for 2021, compared with an EAF of 65% for 2020, 66.9% for 2019 and 71.9% for 2018.
Apart from helping to reduce load-shedding, additional renewables on the system would also help cut Eskom’s diesel usage and reduce reliance on emergency-generation capacity from diesel-powered open-cycle gas turbines (OCGT) and hydropower pumped storage assets.
“What this means is that diesel-fired OCGTs can increasingly be run when they are actually required [to meet sudden changes in demand], because diesel tanks are less often empty at critical times, and the pumped storage can run [and run for longer] when needed,” the report said.
Added together, the net-cost affect had an additional 5,000MW of renewables been online in 2021 would have been a reduction of R2.5bn in Eskom’s costs for the year.
A return to stage 6 or 8?
The failure to close and implement projects under the REIPPPP and the emergency Risk Mitigation Independent Power Producer Procurement Programme (RMIPPPP) on time means that SA now faces “the very real prospect of a return to stage 6 or even stage 8 load-shedding in the foreseeable future”, Meridian said.
“If the average annual coal-plant energy availability factor reduces from the current levels of about 56% to below 50%, our modelling shows a widening generation capacity shortfall of between 5,000MW and 7,000MW (up to stage 7 load-shedding).”
In the absence of further urgent and drastic interventions, load-shedding is likely to increase substantially in the coming years, up to a 10-fold increase in 2026 when compared with 2021.
But this risk could be largely mitigated, the report said, by closing at least 80% of the winning bids for solar and wind projects from Bid Window 5 of the REIPPPP (this will add about 2,000MW), by increasing the size of solar projects under Bid Window 6 from 1,000MW to 3,000MW and wind projects from 1,600MW to 4,000MW, and by gaining access to the full capacity (excluding gas-based projects) of the RMIPPPP projects (about 800MW).
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