There are many common misconceptions when it comes to monitoring solar plants. Check out these facts about solar monitoring:
Myth: If the installation was done well, there is no need to monitor the solar plant.
Fact: Solar plants are a long-term investment. Monitoring protects that investment.
It’s true that the quality of the installation affects the overall health of the solar PV plant, however, many other factors influence power production. Malfunctions occur throughout the lifetime of the plant. These malfunctions affect how much power is produced. Factors like soilage, shading, string failures, or voltage imbalance can all cause loss of power. The primary goal is to detect system failures immediately and correct them quickly for minimal downtime and maximum financial return.
In the example pictured, shading from the close tee caused a visible power loss. It’s likely that the tree was shorter or not there at all when the solar array was installed. As we know, trees grow. The shading by this grown tree caused the plant to produce between 5-10% less than the expected power output. If this plant was not monitored, the power loss would not have been detected and the financial loss would have been significant.
Myth: Small dips in power are nothing to be concerned about.
Fact: Even small dips in power production have a significant, negative financial impact.
It’s a common misconception that when a solar plant produces only slightly less than expected, the financial loss is insignificant. Slight, seemingly insignificant losses add up over time. Gradual changes in solar power production can be difficult to detect without a professional solar plant monitoring tool.
In the example to the right, an improper derating of tracker 3 connected to inverter no. 22 was observed through the Solar-Log® monitoring system. This persistent problem caused a loss between 20-30 kWh per day. If left uncorrected, this small kWh loss could add up to a 930-kWh loss, in just one month. The average electricity cost in the area is $0.12/kWh. That means this “small” loss cost the plant owner $111.60 in just one month.
Myth: Monitoring that comes with the inverter is enough.
Fact: Professional, hardware-independent data logging is needed to ensure all components are working.
Inverter failures may be the source of yield loss, but many other factors could also negatively impact power production, like cable damage, installation errors, shading, or dirty modules. These factors are difficult to detect without an inverter-agnostic monitoring device. Professional monitoring tools detect these hard-to-see malfunctions and report them to the plant operator. Quick detection greatly reduces O&M costs. First by remotely pinpointing of issues which would otherwise go unnoticed, or which would require costly site visits to identify. Next by providing the information so field technicians go directly to the problem area with the right tools and equipment to correct the issue.
Myth: Consumption monitoring is just a feel-good thing for plant owners.
Fact: Consumption monitoring is a valuable, inexpensive tool overlooked by many plant owners and installers.
Consumption monitoring detects changes in plant owner’s usage after the plant has been installed. As soon as customers go solar, they often change the way they use electricity, ultimately increasing usage. To the installer who guarantees certain savings, this knowledge is the difference between gaining or losing customer confidence. For plant owners, once they understand how the energy is used, they can make adjustments to lower electricity costs.
Solar Monitoring Facts Vs Myths: Download the PDF.
