40% renewables by 2030 in South Africa’s power system – what would need to happen?

 

Modeling done by SAWEA, SAPVIA and SESSA with input from CSIR

 The Integrated Resource Plan for electricity in its current version (IRP 2010) foresees an electricity demand in South Africa of approximately 450 TWh/yr by 2030. As a thought experiment: If 40% of these 450 TWh/yr (or approx. 180 TWh/yr) were supplied from renewable sources, what would that require?

A possible scenario would be that wind supplies 20% of the electric energy (85-90 TWh/yr), solar photovoltaic (PV) 15% (65-70 TWh/yr), and the residual 5% (20-25 TWh/yr) would be supplied from biomass, biogas and concentrated solar power (CSP). In this scenario a balance between cost and smoothening of the inherent volatility of wind and solar PV is aimed for.

In such a scenario, approx. 25-30 GW of wind turbines would have to be built (1.5-2 GW/yr until 2030), another 25-30 GW of solar PV (1.5-2 GW/yr until 2030) and 4-5 GW of biomass, biogas and CSP (250-350 MW/yr). This would mean R70-80 billion investments per year until 2030 and stimulating investments into the local manufacturing supply chain of solar PV and wind power generators through a constant annual offtake. The PV fleet would consist of 15-20 GW as embedded and distributed installations, and 10-15 GW as large utility-scale PV power plants, in order to stimulate all segments of this market.

 

To put these numbers into perspective: Spain has an electricity demand of 250 TWh/yr, i.e. significantly less than South Africa by 2030, and an installed wind fleet of 23 GW plus an installed CSP fleet of more than 2 GW. Germany has an electricity demand of 600 TWh/yr, i.e. 1/3 more than South Africa by 2030, and an installed wind fleet of close to 40 GW plus an installed PV fleet of also close to 40 GW, plus an installed biogas fleet of more than 4 GW. The penetration levels as per the 40% scenario are hence not unheard of.

There are however a number of enabling factors that are required in order for this to happen:

  • Widespread spatial distribution of both wind and solar PV projects in order to reduce short-term volatility of the aggregated supply profile.
  • Investments into the grid infrastructure to unlock the potential for wind integration in windy areas where there is no grid today.
  • Streamlining authorizations in order to shorten the timelines for necessary grid expansions
  • Creation of an enabling environment for medium-sized wind and solar PV farms (approx. 1-30 MW per project) that can be connected to the existing grid.
  • Creation of an enabling environment for embedded generators behind customers’ meters*
  • Flexibilisation of the existing conventional fleet to cater for increasing fluctuations of the residual load (system load minus wind supply minus PV supply).
  • Procurement of new, flexible conventional generators such as gas-fired open- and combined-cycle power stations as planned in the IRP.
  • It is estimated that 4-5 GW of flexible power generators in addition to the gas fleet that is planned in the IRP 2010 would have to be procured – the biomass/biogas/CSP fleet would provide that required flexibility.
  • Establishment of a procurement platform that allows cost-efficient procurement of energy (and potentially capacity), as well as reserves and balancing power from a wide range of sources through aggregators/Virtual Power Plants, e.g. distributed dispatchable loads, distributed small-scale power generation.

Further cost reduction of electricity storage in form of batteries will be an added bonus, is however not a necessary condition for achieving a 40% renewables share by 2030.

Assuming that this 40%-share of renewables would replace predominantly coal-fired power generation, renewables would avoid approx. 150-180 million tons of annual CO2 emissions. That is 110-140 million tonnes more than the currently envisaged share of 9% domestic renewables by 2030 would avoid.

In terms of cost implications, both wind and solar PV will soon reach the 0.5 R/kWh mark (wind currently stands at 0.62 R/kWh and PV at 0.79 R/kWh), which makes the mix of wind/PV and flexible power stations one of the cheapest new-build options in South Africa.

 

* These embedded generators could be residential, commercial, industrial and agricultural rooftop solar PV (ranging from a few kW up to many MW in size), small wind farms or individual turbines in rural / agricultural areas, biogas plants in farming communities, biomass plants in forestry-rich areas.