This is an extract from the executive summary of a recent report titled “Operation and Maintenance Best Practice Guidelines: South Africa Edition” published by SolarPower Europe with support from South Africa PV Industry Association (SAPVIA) and GIZ SAGEN
South Africa is Africa’s largest PV market by far and reached GW-scale in 2016. In 2020 the country’s solar capacity stood at 3.7 GW and is expected to increase to just over 10 GW by 2025, according to SolarPower Europe’s business-as-usual scenario. As its fleet of power plants begin to age, proper “health care” is becoming increasingly important and will be vital in maintaining confidence in solar PV as a long-term, sustainable solution to the country’s energy demand. Operation and Maintenance (O&M) has become a standalone segment within the solar industry, and it is widely acknowledged by all stakeholders that highquality O&M services mitigate potential risks, improve the Levelised Cost of Electricity (LCOE) and Power Purchase Agreement (PPA) prices, and positively impact the return on investment (ROI). Responding to the discrepancies that exist in the country’s current solar O&M market, the South Africa edition of the O&M Best Practice Guidelines makes it possible for all to benefit from the experience of leading South African and European experts in the sector, and increase the level of quality and consistency in O&M. These Guidelines are meant to be used by O&M service providers as well as installers, owners, investors, financiers, monitoring tool providers, technical consultants and all interested stakeholders in South Africa.
Environment, health and safety
Environmental problems are normally avoidable through proper plant design and maintenance, but where issues do occur, the O&M service provider must detect them and respond promptly. Environmental compliance may be triggered by components of the PV system itself, such as components that include hazardous materials and by-products that may be used by the O&M service provider such as herbicides and insecticides. In South Africa, water scarcity should be considered in certain arid regions, and it is important to have a plan to avoid local disputes over water.
In many situations, solar plants can support agriculture and are a valuable natural habitat for plants and animals alongside the primary purpose of power production. Solar plants are electricity generating power stations and have significant hazards present which can result in injury or death. Risks should be reduced through proper hazard identification, careful planning of works, briefing of procedures to be followed, documented and regular inspection, and maintenance. Personnel training and certification and personal protective equipment are required for several tasks. Almost all jobs have some safety requirements such as fall protection for work at heights and electrical arc-flash, lock-out tag-out, and general electrical safety for electrical work, eye, and ear protection for ground maintenance.
Whilst the principles of health & safety for ground mounted systems are universal, rooftop C&I installations in the 100kW – 1MW category have different requirements that consider their unique placement on buildings with public access.
Personnel & training
It is important that all O&M personnel have the relevant experience and qualifications to perform the work in a safe, responsible, and accountable manner.
Technical asset management
Technical Asset Management encompasses support activities to ensure the best operation of a solar power plant or a portfolio, i.e., to maximise energy production, minimise downtime and reduce costs. In the South African context, especially in the C&I and residential segments, Technical Asset Management, power plant operation and power plant maintenance, are often assumed by the same entity, the installer. However, in cases where these roles are separated, and the technical asset manager and the O&M service provider are separate entities, close coordination and information sharing between the two entities is indispensable. Technical Asset Management also includes ensuring that the operation of the PV plant complies with national and local regulations and contracts, and also advising the asset owner on technical asset optimisation.
Power plant operation
Operation is about remote monitoring, supervision and control of the PV power plant or portfolio and it is an increasingly active exercise as grid operators require more and more flexibility from solar power plants. Power plant operation also involves liaising with or coordination of the maintenance team. A proper PV plant documentation management system is crucial for operations. Based on the data and analyses gained through monitoring and supervision, the O&M service provider should always strive to improve PV power plant performance. As there are strict legal requirements for security services in most countries, PV power plant security should be ensured by specialised security service providers.
Power plant maintenance
Maintenance is usually carried out on-site by specialised technicians or subcontractors, according to the operation team’s analyses. A core element of maintenance services, Preventive Maintenance involves regular visual and physical inspections, functional testing and measurements, as well as the verification activities necessary to comply with the operating manuals and warranty requirements. The Annual Maintenance Plan includes a list of inspections and actions that should be performed regularly. Corrective Maintenance covers activities aimed at restoring a faulty PV plant, equipment or component to a status where it can perform the required function. Extraordinary Maintenance actions, usually not covered by the O&M fixed fee, can be necessary after major unpredictable events in the plant site that require substantial repair works. Additional maintenance services may include tasks such as module cleaning and vegetation control, which could be done by the O&M service provider or outsourced to specialist providers.
Revamping and repowering
Revamping and repowering are usually considered a part of extraordinary maintenance from a contractual point of view. However, revamping and repowering’s significance has increased rapidly in solar O&M markets around the world, with South Africa being no exception to this. It is expected that revamping and repowering will gain traction in South Africa in the years to come.
Spare parts management
Spare Parts Management is an inherent and substantial part of O&M aimed at ensuring that spare parts are available, in a timely manner, for Preventive and Corrective Maintenance, minimising the downtime of a solar PV plant. As best practice, spare parts should be owned by the asset owner while maintenance, storage and replenishment should be the responsibility of the O&M service provider. It is considered best practice not to include the cost of replenishing spare parts in the O&M fixed fee. However, if the asset owner requires the O&M service provider to bear replenishment costs, a more costeffective approach is to agree which are “Included Spare Parts” and which are “Excluded Spare Parts”.
Data and monitoring requirements
The purpose of the monitoring system is to allow supervision of the performance of a PV power plant. Requirements for effective monitoring include dataloggers capable of collecting data (such as energy generated, irradiance, module temperature, etc.) from all relevant components (such as inverters, energy meters, pyranometers, temperature sensors) and storing at least one month’s worth with a recording granularity of up to 15 minutes. In addition, a reliable Monitoring Portal (interface) is needed for visualising the data collected and calculating KPIs. Satellite data is being used increasingly as a comparison reference for on-site pyranometers. As a best practice, a monitoring system should ensure open data accessibility to enable an easy transition between monitoring platforms and the interoperability of different applications. As remotely monitored and controlled systems, PV plants are exposed to cybersecurity risks. It is therefore vital that installations undertake a cyber security analysis and implement a cybersecurity management system.
Key Performance Indicators
Important KPIs include PV power plant KPIs, directly reflecting the performance of the PV power plant; O&M service provider KPIs, assessing the performance of the O&M service provided, and PV power plant/O&M service provider KPIs, which reflect power plant performance and O&M service quality at the same time. PV power plant KPIs include important indicators such as the Performance Ratio (PR), which is the energy generated divided by the energy obtainable under ideal conditions, expressed as a percentage, and Uptime (or Technical Availability) which are parameters that represent, as a percentage, the time during which the plant operates over the total possible time it can operate. O&M service provider KPIs include Acknowledgement Time (the time between the alarm and the acknowledgement), Intervention Time (the time between acknowledgement and reaching the plant by a technician) and Resolution Time (the time to resolve the fault starting from the moment of reaching the PV plant). Acknowledgement Time plus Intervention Time are called Response Time, an indicator used for contractual guarantees. The most important KPI which reflects PV power plant performance and O&M service quality at the same time is the Contractual Availability. While Uptime (or Technical Availability) reflects all downtimes regardless of the cause, Contractual Availability involves certain exclusion factors to account for downtimes not attributable to the O&M service provider (such as force majeure), an important difference for contractual purposes.
In the South African market, O&M service providers are mostly required to provide Performance Ratio guarantees, particularly in the case where a project is funded through project finance. PR guarantees are particularly suitable in cases where installer is the same entity as the O&M service provider, which is often the case in South Africa. In certain cases, parties agree to use Availability and Response Time guarantees. As best practice a minimum Availability of 98% over a year should be guaranteed, with Contractual Availability guarantees translated into bonus schemes and liquidated damages. When setting Response Time guarantees, differentiating between periods with high and low irradiance levels is recommended. The same goes for fault classes, i.e., the (potential) power loss.
The complete report can be accessed here