Panel mismatch occurs when lower performing panels pull down the performance of neighbouring panels in the same string. The causes of panel mismatch vary and include manufacturing tolerance, panels aging at different rates
, shading, soiling, bird droppings, snow, and fallen leaves blocking the sunlight. Panel mismatch reduces the output of solar energy systems, which decreases system ROI.
Photovoltaic (PV) Panel
A PV panel, also referred to as a solar panel, is comprised of photovoltaic solar cells connected in a series. PV panels are installed on the rooftop where they absorb photons (light energy) to generate electricity. PV panels are connected in a string to form a complete solar-power-generating unit called a PV array.
Power density is the amount of power per mass. PV inverters are measured by power density. The higher the power per mass, the better the inverter.
Connected by installers to each solar panel, power optimisers
are a DC to DC converters designed to maximize energy harvest from PV systems by individually tracking the maximum power point of each individual panel. Advanced power optimisers turn every solar panel into a smart panel. Power optimisers are also responsible for monitoring the individual panels performance.
PV inverters were originally developed to convert direct current (DC) generated by PV panels to alternating current (AC) for use in the home or to feed into the grid. One of the most common types of inverters is a string inverter, which performs both conversion and MPPT at the string level.
Standard string inverters offer limited monitoring possibilities, create energy losses, limit design flexibility, and in some regions require the installation of additional safety hardware. Other types of inverters available are DC-optimised inverters and micro-inverters.
In recent years the role of the PV inverter has expanded into smart energy management, including storage, grid interaction, home energy, EV charging, monitoring, safety, and more.
A solar energy monitoring system
offers information about the performance of the PV system, such as, how much energy is produced, consumed, and fed into the grid. Without high-resolution monitoring, it can be challenging to understand the PV system’s performance. Monitoring increases a system owner’s insight into their PV system’s performance and helps them understand if something needs to be repaired. Furthermore, monitoring often allows for installers to perform remote troubleshooting, which means quicker problem-solving and higher system uptime. There are different types of PV monitoring – embedded monitoring systems, add-ons, monitoring at the string-level, and monitoring at the panel-level. panel-level monitoring provides the highest resolution insight.