Large-Scale PV Operations and Maintenance

Well-planned O&M helps mitigate 30 years of risk.

Using solar power is essentially prepaying for energy—or prepaying for fuel, in the parlance of utilities—30 years in advance. PV requires harnessing the sun’s power today and every day for the next 30 years. On a missed operational day, solar radiation is dissipated as heat. This is a lost opportunity, like pouring gasoline onto the ground. Even one day of lost energy is wasted potential. This is why the operations and maintenance (O&M) aspect of a PV system is so important. Nevertheless, it is often overlooked.

Despite the fact that PV systems are low maintenance, they are not completely maintenance free. Solar is an excellent, reliable source of power, but PV systems must be diligently observed and operated to capture as much of the convertible power as possible. In this way, owner/operators can achieve the benefit necessary to pay off their investment. Many developers try to convince investors that panels can be forgotten once they are turned on. This oversimplification underestimates O&M and allows developers to reduce cost assumptions to boost profitability.

These assumptions are hard to challenge since independent engineers typically do not have 30 years of failure history to refer to. According to Sarah Disch, director of operations for Fotowatio Renewable Ventures, “The cost of corrective maintenance is largely unknown, and it is not clear that the relatively small operating budgets established during project financing for 20-plus years will be sufficient.” Because the future costs for unscheduled maintenance due to failures are an unknown, all parties are reluctant to predict on the low end of probability. Sometimes the resulting high-end prediction creates an O&M budget that stops a potential system from being built.


O&M for PV systems is managed differently from plant construction. Optimal operations must strike a balance between the most productive system and the one with the lowest costs. Operational decisions are challenged by the financial structure, the maturity of the industry and economic returns. Many maintenance providers offer O&M as a guaranteed service to encourage the sales process. Operations are also about the organization and management of contract obligations. The engineering, procurement and construction (EPC) contractors are not necessarily equipped to manage multiple long-term contracts with layers of guarantees.

Operations are often like death by a thousand (paper) cuts. Maintaining a plant has less to do with the actual work in the field and more to do with data analysis, potential issues and contract management. Large systems are subject to layers of obligations by the project sponsor, EPC contractor, subcontracted parties, insurance provider, utility, site host and so on. These systems can have thousands of pages of project documents. Understanding each of these documents is essential to ensure the owner is not overpaying and is getting the services promised. While O&M contracts are individually negotiated, providers may not recall the specific nuances of a deal, tending instead to treat all operations similarly. It is just as important for the service provider to be well versed in these contracts. The owner may ask for what seems like prudent service, but it may not be covered in the service contract. These service contracts are subject to myriads of lawyers and red pens. They may not be nearly as boilerplate as they appear.

O&M is a mindset that requires the strategic evaluation of a system to know how to predict the economic and contractual impact against less-than-optimal performance. Understanding the expected costs means budgeting accordingly. Once the system is in operation, understanding the financing structure is crucial. The most technically prudent solution may not be the best for the project. Finally, O&M is a daily exercise. It cannot necessarily be scheduled quarter-byquarter into the future. An operations team must understand the overall system performance, observe trends and help prevent problems or solve them immediately after they occur.

The solar O&M market is mostly made up of integrators who were forced to provide operational guarantees to sell products over the past approximately 5 years. This creates some inherent challenges. For example, EPC contractors are still being obliged to provide commitments to system performance that are not part of their focus. These large organizations have small groups focused on operations attempting to fulfill commitments made by a sales team years earlier. It can be difficult for PV system owners to get the service they paid for from the large construction company.


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