South Africa can cut carbon emissions by half with 50% renewable energy mix

In the low scenario, where renewables reach 30% of total capacity, emissions drop by 30% and load-shedding by 25%, but these gains fall short of international benchmarks. The system remains vulnerable to coal plant failures, and infrastructure costs rise modestly by 10%. This pathway, according to the study, represents limited ambition and fails to unlock economies of scale or investor confidence.

South Africa’s energy transition could achieve a 50% cut in carbon emissions and a 40% drop in load-shedding within a decade if renewable energy integration reaches half the national power mix, according to a new study by researchers from the University of South Africa. The research presents a data-driven roadmap for balancing economic cost, energy reliability, and environmental sustainability in one of the world’s most coal-dependent economies.

Published in Renewable Energies and titled “Renewable Energy Integration in South Africa: A System Dynamics Comparison with Global Trends,” the study applies system dynamics (SD) modeling to simulate how varying levels of renewable energy adoption could reshape the country’s grid stability and emissions landscape by 2035. The findings carry sharp policy implications, positioning renewable energy as both an environmental necessity and an economic strategy to counter the country’s prolonged electricity crisis.

Can system dynamics reshape South Africa’s coal-heavy grid?

The authors argue that South Africa’s electricity sector, dominated by coal, which accounts for 72.7% of the energy mix, faces systemic vulnerabilities that cannot be solved through piecemeal reforms. Load-shedding, which has persisted since 2007, continues to impose heavy financial losses and public frustration, while the country ranks among the world’s top ten carbon emitters. The Integrated Resource Plan (IRP 2019) set an ambitious target of adding 30.7 gigawatts of renewable capacity by 2030, aiming to mitigate these pressures. Yet, intermittent supply, underdeveloped infrastructure, and regulatory uncertainty have hindered progress.

The study employs system dynamics to understand these challenges through interlinked feedback loops that capture the economic, environmental, and social dimensions of energy transition. By modeling the interplay between renewable capacity, coal dependency, emissions, and system costs, the researchers demonstrate how reinforcing and balancing mechanisms can either accelerate or stall the transition. This holistic approach reveals that energy reliability, investment timing, and policy consistency are deeply interconnected—shifts in one can amplify or constrain others.

Historical data show how Eskom’s reliance on coal infrastructure, built since 1923, entrenched economic and spatial inequalities. Although post-1994 electrification policies expanded access, they also intensified dependence on coal-based generation. The study suggests that the very structure of South Africa’s energy system, centralized, carbon-intensive, and capital-heavy, requires a dynamic reform model rather than static planning.

How much renewable energy is enough? A scenario-based outlook to 2035

To test the implications of renewable adoption, the researchers simulated three scenarios for 2035: low (30%), medium (50%), and high (70%) renewable shares. Each scenario was designed to evaluate the balance between emissions reduction, load-shedding relief, and cost escalation.

In the low scenario, where renewables reach 30% of total capacity, emissions drop by 30% and load-shedding by 25%, but these gains fall short of international benchmarks. The system remains vulnerable to coal plant failures, and infrastructure costs rise modestly by 10%. This pathway, according to the study, represents limited ambition and fails to unlock economies of scale or investor confidence.

The medium scenario, with renewables supplying 50% of the mix, emerges as the most viable and cost-effective balance. Here, emissions are halved, from 450 to 225 megatonnes of CO₂ equivalents, and load-shedding hours fall from 3,000 to 1,800 per year. The additional cost, about 15% higher than the current baseline, is offset by improved energy reliability and reduced dependence on fossil fuels. This equilibrium mirrors strategies adopted in countries such as Malaysia and Kenya, where diversified renewable portfolios reached similar targets while maintaining affordability and resilience.

In the high scenario, a 70% renewable share delivers the deepest decarbonization, cutting emissions by 65% and load-shedding by 55%. However, it also increases infrastructure costs by 25%, driven by the high capital investment required for grid upgrades and energy storage. The authors warn that without phased coal retirements and expanded energy storage, such an aggressive transition could strain public finances and threaten grid stability.

The results underline that South Africa’s optimal pathway lies not at the extremes but in an adaptive mid-point. A 50% renewable mix by 2035 could transform the country’s energy security while maintaining economic feasibility, especially if supported by robust governance, private-sector participation, and community-level initiatives.

What policies can deliver a stable and equitable energy transition?

Renewable expansion must be supported by financial, technological, and social mechanisms that sustain momentum over time. The system dynamics model identifies key leverage points such as storage subsidies, demand-response incentives, and data-driven planning as essential tools to stabilize the grid during transition.

The authors estimate that achieving a 50% renewable share would require an investment of roughly USD 5.56 billion in storage and grid modernization. Time-of-use tariffs, capable of shifting 5–10% of industrial energy demand, could save an additional USD 0.56 billion annually by flattening peak consumption. Meanwhile, carbon capture technologies could remove up to 20% of residual emissions from remaining coal plants, easing the financial burden of rapid decommissioning.

Community-based projects, notably the solar initiatives in Enkanini, demonstrate how decentralized generation can complement national strategies. These locally managed systems not only enhance adoption but also reduce Eskom’s infrastructure load and empower rural populations. Yet, the researchers note that limited data on rural energy demand remains a critical blind spot. Integrating satellite imagery with on-the-ground surveys, they argue, would refine projections and improve the inclusivity of future energy planning.

Globally, the study’s comparative analysis draws lessons from Finland’s policy coherence, Malaysia’s integrated subsidies, and China’s industrial decoupling of emissions from growth. South Africa’s policymakers, the authors conclude, can adapt these best practices through context-sensitive reforms, balancing ambition with realism and ensuring that decarbonization aligns with economic stability.

A regional model for Sub-Saharan energy transitions

The research provides a blueprint for other coal-heavy economies in Sub-Saharan Africa. Countries like Kenya, Ethiopia, and Ghana face similar structural challenges: outdated grids, limited storage capacity, and fragmented policy execution. Mathibedi and colleagues propose that system dynamics modeling can serve as a regional tool for testing policy outcomes before implementation, allowing decision-makers to anticipate trade-offs between cost, reliability, and sustainability.

Overall, South Africa’s energy transformation depends on coherent regulation, sustained financing, and evidence-based policy iteration. By 2035, a balanced renewable strategy could not only stabilize the grid but also reposition the country as a leader in low-carbon transition across the continent. The authors emphasize that while a high-renewable system offers impressive environmental gains, the mid-level 50% integration remains the most practical and resilient trajectory for balancing growth with sustainability.

Their findings reaffirm that the future of South Africa’s energy security is not merely about replacing coal with renewables but about managing the transition as a dynamic system, one that continuously learns, adapts, and balances competing priorities. With proper investment, regulatory clarity, and data-driven foresight, South Africa could move from chronic load-shedding to long-term stability, setting a model for sustainable development across the region.