• South Africa does not have a renewable energy ambition problem. It has a grid problem. The Integrated Resource Plan 2025 is unusually frank about this, and the numbers it puts on the table deserve the same level of attention as the megawatt targets that tend to dominate the conversation.

There is a version of the South African energy transition story that focuses almost entirely on generation. How many megawatts of wind. How much solar. What the pipeline looks like. These are important questions and the IRP 2025 answers them with considerable specificity. But there is a quieter set of numbers in the same document that tells a more complicated story, and it is the story of the grid.

The transmission network is the infrastructure that moves electricity from where it is generated to where it is needed. In South Africa, that infrastructure has not kept pace with the ambition of the generation programme. The IRP 2025 is direct about this. It notes that the grid connection queue for generation projects is extensive, that available transmission capacity in the richest renewable resource areas is already constrained, and that resolving this constraint is the single most consequential infrastructure challenge facing the energy transition over the next decade.

The scale of what needs to be built

The IRP 2025’s Transmission Development Plan, detailed in Section D, sets out a specific and demanding infrastructure requirement. 14,494 km of new transmission lines must be built by 2034. Of that total, 5,044 km is required by 2029. This is not an aspirational target. It is the minimum network expansion the modelling shows is necessary to accommodate the committed generation capacity already in the pipeline, let alone the new build required through to 2050.

IRP 2025, Section D, 1.3 Results: ‘14,494 km of new lines will be required by 2034 to accommodate the increased generation and demand requirements. 5,044 km of these lines are required by the year 2029.’

To understand what 14,494 km of transmission infrastructure means in practical terms, it helps to consider what building it requires. New transmission corridors require servitude acquisition across private, communal and government-owned land. The IRP 2025 identifies servitude acquisition as the primary implementation risk for the TDP, noting that the process involves multiple layers of stakeholders and is expected to significantly influence the pace at which TDP projects are implemented. The document calls for proactive engagement with the Department of Public Works and Infrastructure as essential, particularly regarding land expropriation and access to government-owned land.

IRP 2025, Section D, 1.4 Implementation Challenges and Solutions: ‘The primary risk to the successful delivery of the TDP 2024 lies in the anticipated challenges associated with servitude acquisition. As this process involves multiple layers and stakeholders, it is expected to significantly influence the pace at which TDP projects are implemented.’

In other words, the bottleneck is not only technical. It is legal, administrative and political. New transmission lines cannot be built faster than the land rights process allows, and that process has historically moved slowly in South Africa.

The 134 GW problem

One of the most striking figures in the IRP 2025 is the scale of developer interest in renewable energy generation. According to the South African Renewable Energy Grid Survey conducted in July 2024 and cited in the IRP, there is up to 134 GW of potential wind and solar development interest from private developers across the country. This figure reflects the type, location and quantum of projects that developers have registered as potential development opportunities.

IRP 2025, Section C, 2. IRP Modelling Approach: ‘According to the Grid Survey, which surveys the interest of renewable energy development, including the type, location and quantum, there is up to 134 GW of potential.’ Citing: South African Renewable Energy Energy Grid Survey, July 2024, NTCSA.

134 GW of developer interest sitting behind a grid that currently has 5,344 MW of installed wind capacity and approximately 3,646 MW of grid-tied solar PV is a structural mismatch of considerable scale. The gap between what developers want to build and what the grid can absorb is not primarily a question of financing or technology. It is a question of transmission capacity, and the IRP 2025 is clear that closing that gap requires the kind of sustained, coordinated infrastructure investment that South Africa has not yet demonstrated it can deliver at pace.

IRP 2025, Section C, Figure 20: South Africa’s Installed Capacity by Technology Diversity in 2025. Wind: 5,344 MW. Solar PV Grid-tied: 3,646 MW.

The committed pipeline and the IGCAR problem

Even within the committed pipeline, the grid constraint is visible. The IRP 2025 notes that private committed generation projects total approximately 13 GW. Of that total, roughly 55% are either operational, in execution or have budget quotations issued. The remaining 45% are at the Interim Grid Capacity Allocation Rules (IGCAR) stage, meaning they have applied for grid connection but have not yet secured it.

IRP 2025, Section C, 3.4 Committed Private Generating Capacity: ‘Approximately 55% worth of projects are either operational, in execution or have budget quotes issued. The remaining 45% are at the Interim Grid Capacity Allocation Rules (IGCAR) stage.’ Total private committed capacity: approximately 13 GW.

The IGCAR was introduced by Eskom in 2023 to manage the growing demand for grid access amid severe grid constraints. It operates on a first-ready, first-served basis, prioritising projects that are technically and commercially ready to connect. The IRP 2025 describes it as a shift away from the previous first-come, first-served approach. What this means in practice is that approximately 5.85 GW of privately committed generation projects, projects with completed permitting and secured financing, are waiting for grid connection capacity that does not yet exist in their preferred interconnection zones.

For the total committed generation capacity across all categories to reach the IRP’s projected 44,434 MW by 2030, grid connection must keep pace with project development across public, private and Eskom programmes simultaneously. The IRP’s own modelling acknowledges this as a binding constraint, not a background assumption.

IRP 2025, Section C, Figure 7: Total Committed Generating Capacity. Grand Total projected to reach 44,434 MW by 2030, adding 15,250 MW of new capacity from 2025 baseline across all technologies.

System flexibility: the second-order grid problem

Beyond raw transmission capacity, the IRP 2025 identifies a second and related grid challenge that becomes more acute as the renewable share of the energy mix increases. Section C, 7 of the document addresses power system flexibility in detail. A flexible power system is one that can adapt quickly and reliably to changes in electricity demand or supply, including the variability introduced by wind and solar generation.

South Africa’s current power system is dominated by older coal-fired plants that are not designed for rapid changes in output. As the share of variable renewable energy increases, the system requires an increasing proportion of generation that can ramp up or down quickly to balance supply and demand. The IRP 2025 notes that in 2030, when 8 GW of coal-fired stations are expected to shut down, the contribution of variable RE in the energy mix increases to 23%. At that point, the flexibility requirement becomes significantly more demanding.

IRP 2025, Section C, 7.3 Medium to Long-Term Flexibility: ‘In 2030 when 8 GW of coal-fired stations shut down, the contribution of variable RE in the energy mix increases to 23%. This coincides with the planned commissioning of 6 GW of new gas CCGT.’

The IRP’s flexibility analysis demonstrates that by 2040 there is a meaningful and growing probability of risk in meeting residual demand, with shortfall magnitudes ranging from 6.5 GW to 12.7 GW by 2040 and between 9 GW and 12 GW by 2045. These figures do not represent projected failures. They represent the risk profile the system carries if flexible dispatchable generation, storage and transmission infrastructure do not develop in parallel with variable RE build.

IRP 2025, Section C, 7.3 Medium to Long-Term Flexibility: ‘The magnitude of the shortfall ranges from 1.4 GW to 3.8 GW and from 2.7 GW to 8 GW in 2030 and 2035, respectively. The magnitude of risk increases with 2040 showing a shortfall ranging between 6.5 GW to 12.7 GW and 2045 shortfall ranging between 9 GW and 12 GW.’

What the grid constraint means for sector participants

For developers, the grid constraint means that project development strategy must account for transmission availability from the earliest feasibility stage. The richest wind resource areas in the Cape are also the most constrained in terms of available connection capacity. Projects that are development-ready but cannot reach financial close because of grid queue dynamics represent a real and growing cost to the sector, both in capital tied up in development expenditure and in the delay of generation that the system needs.

For investors, the constraint adds a layer of risk that is not always fully priced into project timelines and financing structures. A project that assumes grid connection by a certain date is exposed if the TDP programme slips, if servitude acquisition takes longer than planned, or if the queue ahead of it does not clear at the pace expected. The IRP 2025 treats these not as theoretical risks but as the primary implementation challenge for the transition period to 2030.

For asset managers and O&M service providers, the grid constraint creates an indirect but important implication. In a system where new capacity is constrained from entering the grid, the performance of existing installed capacity becomes more valuable, not less. Every megawatt-hour that an existing wind farm fails to generate due to unplanned downtime is a megawatt-hour the system cannot replace quickly. The operational discipline of the existing fleet matters more in a constrained grid environment, not less.

The R2.23 trillion question

The IRP 2025 presents a R2.23 trillion investment plan for South Africa’s energy future. The generation side of that plan has received most of the attention, as it should. But a significant portion of that investment needs to flow into transmission infrastructure, and the pace at which it does will determine whether the megawatt targets in the Reference Case are achievable within the timeframes the plan assumes.

IRP 2025, Executive Summary: ‘The IRP 2025 presents a R2.23-trillion investment plan that defines South Africa’s energy mix to drive the government’s deliberate effort to grow the economy for the future.’

The grid is not the obstacle to South Africa’s energy transition. It is the enabler. And until the transmission programme is funded, accelerated and delivered at the scale the IRP 2025 requires, the gap between South Africa’s renewable ambitions and its renewable reality will remain wider than the generation pipeline alone suggests.

At Artemis Group Holdings, we read the IRP 2025 not just for its procurement signals but for its honest account of the constraints the sector faces. Understanding those constraints, and working within them with rigour and realism, is what the transition actually requires.

Source

Integrated Resource Plan 2025, Department of Electricity and Energy, Republic of South Africa. Published in Government Gazette No. 53596, 28 October 2025. Available at: www.gpwonline.co.za