South Africa’s total installed solar capacity now exceeds 10 GW according to the CSIR, with around 60% made up of private-sector installations developed by mines, manufacturers, data centres and other large electricity users seeking greater energy security and cost stability.
One of the most important and least appreciated determinants of the success of these generation assets is operations and maintenance (O&M), particularly given that they are expected to perform reliably over a two- to three-decade lifespan.
JUWI has been involved in operating utility-scale and commercial and industrial solar plants across South Africa and globally for many years, including some of the country’s earliest and most established projects such as utility-scale RustMo1 and Solar Capital De Aar 1, as well as plants developed for large energy users such as Pan African Resources.
In SA alone, we’ve operated 13 projects over the past 15 years, across behind-the-meter, grid-connected and hybrid plants. This is supported by the broader JUWI Group’s international O&M experience, including projects in Australia, Italy, Greece and Germany. JUWI’s global control rooms currently monitor more than 200 solar plants around the world, about 1.8 GW of capacity.
Our experience shows that ultimate performance and returns are not only determined by how the project is developed and built, but how these assets are operated and maintained.
Projects success depends on people
There is a tendency in the market to treat O&M as something that follows development and construction. O&M is often treated as an afterthought, when in reality it is where projects ultimately succeed or fail.
In practice, plant performance is shaped by the full operating regime. That includes the capability of the on-site team, the tools and systems available to them, the structure of the operating plan, and the level of support from both internal teams and equipment manufacturers.
Of these, the people, the team, is the most important. Well-trained personnel who understand the plant, the systems and the procedures make the biggest difference, particularly in South Africa where many plants are located in remote areas. In these environments, teams often need to make fast decisions on site, without immediate external support.
Even a well-designed plant will underperform if the operational capability on the ground is weak. On the other hand, experienced teams can improve performance over time through careful observation, disciplined maintenance and good judgement.
Managing equipment quality and manufacturer dependencies
One of the less obvious realities in solar operations is that performance isn’t only determined by the plant itself, but also by how much operators depend on external suppliers.
Equipment failure is the most common performance issue we see in operating plants, particularly as they begin to age. However, the impact of these failures is not just about the fault itself, but how quickly it can be diagnosed and resolved – and that is where both equipment quality and original equipment manufacturer (OEM) support become critical.
In practice, the choice of equipment and OEM at the outset has a direct impact on how manageable a plant is over time. Cheaper equipment can introduce higher failure rates, limited support, and greater dependence on suppliers that may not be locally present or responsive. By contrast, well-supported, higher-quality equipment tends to be more reliable and easier to operate over the long term.
That said, even in well-designed plants, some level of OEM dependency is unavoidable. This is where strong O&M capability makes a significant difference. While some issues require direct OEM involvement, experienced teams are able to troubleshoot, isolate and, in some cases, resolve problems locally, reducing reliance on external response times.
We saw this play out on site. In one case, an issue with the tracker control system required intervention from a supplier in Europe. During a transition between companies, access to the system became difficult, and parts of the plant we were managing remained underperforming while support requests were escalated. Rather than waiting indefinitely, the team worked with internal specialists to develop a local workaround, restoring control of the system and improving performance.
This highlights that effective O&M is also about managing dependencies actively – from making the right equipment choices upfront, to building local capability and ensuring that plant performance is not unnecessarily constrained by factors outside the operator’s control.
Planning for long-term performance beyond year five
As plants mature, the focus moves from routine maintenance to how well the asset has been set up to deal with what comes next.
From around year five onwards, failure rates start to increase, and questions around spares, warranties and OEM support become much more real. At that point, performance is shaped as much by decisions made during development as by what happens on site day to day.
Owners generally have a few options. Some choose to take out extended warranties on equipment, so the OEM remains responsible for spares and long-term support. Others prefer to buy and hold critical spares on site, which can reduce reliance on external supply chains.
Both approaches come with trade-offs. Extended warranties can give you continuity and peace of mind, especially where equipment may be discontinued over time. Holding spares can improve response times, but it also comes with cost, storage considerations, and the risk that components degrade over time.
In practice, we’ve seen that there isn’t a single right approach. What matters is that these decisions are thought through upfront, with a clear view of how the plant will be operated over the long term.
From an O&M perspective, this is where the work becomes more hands-on. It means planning ahead for replacements, working closely with OEMs, and adjusting maintenance approaches as the plant evolves.
For owners, we always highlight that long-term performance doesn’t just happen. It needs to be planned for.
Visibility is everything: if you can’t see it, you can’t fix it
Real-time monitoring is often seen as a given in modern solar plants, but its value goes beyond simply collecting data – visibility allows teams on the ground to act.
In practice, monitoring feeds into a structured response chain. JUWI’s control rooms – including a central control room in Greece – track plant performance continuously, with seasoned engineers monitoring equipment status, flagging alarms and identifying potential issues.
Site teams also have access to the same monitoring systems on site, so they see the same alarms and performance data in real time and can respond immediately.
When an issue is detected, it is flagged and acted on straight away. In many cases, the control room will notify the site team directly, while the team on site is already checking the system and dispatching technicians to investigate.
We see this most clearly in situations such as grid curtailment. When a plant is curtailed, the control room identifies the event immediately and notifies the site team, which then informs the asset owner. The owner can then meet their contractual obligations, such as notifying the single buyer office (SBO).
Without this chain of visibility and response, what looks like a technical issue can quickly become a commercial one.
The value of monitoring therefore lies less in the data itself, and more in how quickly it leads to action.
This also highlights the importance of clear communication and strong working relationships between all parties involved. Solar plants are long-term assets, often involving multiple stakeholders, including IPPs, owners, EPCs and O&M providers. Effective O&M relies not only on technical capability, but on transparency, clear escalation pathways and keeping all stakeholders informed when issues arise.
In practice, this means working with O&M partners who are proactive in their communication and open about what is happening on site. Issues can then be addressed more quickly, with everyone aligned on the response and the implications.
Good O&M is about judgement, not just maintenance
While structured maintenance plans and monitoring systems are essential, the quality of O&M ultimately comes down to experience, good judgement and the discipline to adhere to procedure even when it is tempting to skip steps to improve short term performance metrics.
Operators are often required to make decisions under pressure, balancing the need to restore production quickly with the need to manage risk.
We’ve seen situations where there is pressure to restart a plant immediately after a trip to recover lost generation. In one case, the team followed procedure and carried out fault-finding first rather than re-energising the plant straight away. This identified a high-voltage issue that could have caused significant equipment damage – and potentially safety risks – if the plant had simply been switched back on. While the delay resulted in short-term production losses, it avoided a far more serious outcome.
Small operational improvements can deliver meaningful gains
Good O&M can also improve plant performance over time.
As teams build up experience on a plant, they start to see patterns in how it behaves under different conditions. This creates opportunities for optimisation, often through relatively small adjustments.
In one instance, we worked with a site team to fine-tune a tracker system. This reduced the frequency of faults and improved alignment, which in turn improved overall plant performance.
These kinds of changes may seem minor, but over the lifetime of a plant they can translate into significant gains in energy yield.
The cheapest plant is often the most expensive to operate
We alluded earlier to the fact that procurement decisions made during development have long-term consequences.
Lower-cost equipment may reduce upfront capital costs, but it often leads to higher and earlier failure rates, limited support, and greater complexity over time. Higher-quality equipment, supported by strong OEMs, tends to be more reliable and easier to maintain.
We have seen that plants equipped with higher-quality components can operate for more than a decade without major failures, while others require more frequent intervention and earlier replacement of key components.
The true cost of a solar plant therefore goes beyond its build cost. It includes the cost of operating and maintaining the asset over its full life.
The best plants are designed for O&M from day one
One of the clearest lessons from operating solar plants is that many operational challenges can be avoided through better design.
Decisions made during development and construction – such as equipment layout, access routes and infrastructure placement – have a direct impact on how easily a plant can be maintained.
We often see how relatively simple design choices make a big difference in practice. For example, positioning key components closer to access routes can reduce maintenance time and improve safety, compared to layouts where teams need to walk deep into the plant to reach equipment.
Involving O&M teams early in the design process allows these considerations to be built in from the start.
Conclusion
South Africa has made significant progress in building solar capacity at scale. The next phase will be defined not only by how much capacity is added, but by how well that capacity performs over time.
For plant owners and IPPs, operations and maintenance will play a central role in determining that outcome.
In many ways, the real test of South Africa’s solar boom will not be how quickly new plants are built, but how reliably they operate over the next two to three decades.