The cost of solar energy has changed drastically over the years, with module prices plummeting from $4/Watt in 2008 to around $0.65/W today (source). Solar Operations and Maintenance (O&M) is changing rapidly as well, in response to continuing efforts to further reduce costs. New technologies are driving changes in solar O&M, but, unlike modules, O&M can’t be commoditized. Different power plants require unique and sometimes contrasting O&M programs. This article presents an approach to identify effective O&M strategies.
All solar plants will bear O&M costs throughout their lifecycle. Some examples are staffing for site access and plant controls, equipment inspection and service, module cleaning, and emergency response to unplanned failures or events. The objective of a well thought-out O&M strategy should be to maximize energy output with minimal cost for ongoing operation.
The capacity of a plant, location, value of energy and more will drive what type of O&M program is effective. A 10kW solar plant may require only a few hours of O&M work per year, while plants on the scale of 100MW often staff full time operators. While there are obvious differences in planning for very large compared to very small plants, there are two core O&M philosophies: do nothing until it breaks, or do everything possible to prevent it from breaking. The “wait to break” approach can expose the plant to long unplanned outages, and the preventive path can introduce unnecessary expense in the name of caution. The optimal O&M program carefully balances these extremes.
Specific O&M activities can vary widely in cost, frequency, and technologies used. When considering which O&M activities are effective for a given plant, there is a common metric to measure it’s return: Levelized Cost of Energy (LCOE). LCOE is a well-known metric in the solar industry, and is used by solar developers to establish a normalized cost of producing energy. The concept of LCOE is simple: all the costs to build and operate the plant are divided by the total energy output of the plant.
O&M strategies can be evaluated using LCOE by comparing the cost of the specific strategy to the expected effect on plant energy output. After establishing the unit cost for the O&M strategy, comparison to the revenue for a unit of energy shows if the strategy is profitable for the plant.
For example, how much does it cost to clean your solar panels compared to the increased energy yield from cleaning? Some solar owners are finding panel cleaning doesn’t always pay off. This simple approach can be used to evaluate various O&M strategies including annual maintenance plans, software and monitoring services, and stocking replacement parts or equipment.
Emerging technologies promise to change the solar O&M landscape, and the Internet of Things (IoT) is particularly promising. IoT starts with the premise that all devices should be securely connected to the internet, then leverages that connectivity to deliver ongoing value through interconnecting various data systems and platforms. While there have been industrial networks and controls solutions since before the internet, those solutions today are not cost-effective and can’t always deliver the level of compatibly and flexibility needed. IoT solutions that can drive value in solar O&M include low-cost, reliable, distributed sensing and data processing, wireless transmission, and highly interoperable system architectures. Dropping costs and rising reliability are evident in smart cities, homes, and solar energy IoT applications all over the world.
Ultimately, when it comes to O&M for solar plants, there is no one-sized approach. Third party O&M providers may be more interested in selling more services than optimizing for LCOE performance. O&M planning should be adapted for plant size, location, value of energy, cost of labor and other relevant factors, using the concept of LCOE for evaluation. When selecting O&M technologies and strategy, understand the options, be strategic and proactive about research, and make an informed choice that fits with your objectives.
Contact: Dan Bigelow
Sr. Director of Customer Success, infiswift