The history of the global PV industry is one that is defined by innovation. And now, more than ever, the continuing growth and sustained health of the solar sector is further enabling companies to invest in R&D. From tech start-ups to global electronics companies, new components that deliver marginal improvements or game-changing solutions, the efficiency and performance of PV systems across the world continues to be advanced by technological innovation.
One characteristic that unites innovators across the solar industry is the unwavering focus on optimizing solar PV systems, always looking to deliver higher yields, reduce O&M costs and increase the ROI for system owners. So, it’s perhaps unsurprising that in recent years there has been a significant increase in the use of module-level power electronics (MLPE), such as power optimizers or microinverters. As the name suggests, MLPE place power electronics on the modules of the PV system, with the aim of isolating individual panels in order to improve overall system performance.
The introduction of MLPE marks a shift from the conventional PV system design, where the inverter would be responsible for handling so many of the functions and processes that a PV plant is required to carry out. The proliferation of MLPE has in part been driven by the strong levels of sustained growth that the residential PV segment has witnessed in recent years. Given the huge variety of customer requirements and differing residential layouts that need to be accommodated, the increased flexibility that MLPE facilitates means that they are being increasingly incorporated into residential PV systems.
The rise of MLPE
The two main MLPE that are currently being used across the solar industry are microinverters and power optimizers. Microinverters are smaller inverters placed on each solar module, either integrated into the panel or placed on the panel mount. With PV systems utilizing microinverters, there is no need for a separate string or central inverters, as the DC current generated by the array is converted to AC right at the site of the panel. Power optimizers are also installed at each panel, though instead of converting the DC energy to AC, they increase the power yield of the module before sending an optimized DC voltage to the system inverter for conversion. They do this by tracking the maximum power point of each individual module, fixing the voltage of the DC energy so that the inverter can convert it more efficiently to AC, fully utilizing the rooftop and removing restriction concerns.
The increase in uptake of MLPE can also be attributed to well-informed customers wanting to get the most from the solution they have. In the age of fitness applications monitoring steps walked each day to smart meters monitoring energy usage in real time, there is a want from customers for more detail on many aspects in our life and none more so than in the solar industry. MLPE help to facilitate module-level monitoring, providing the customer with the ability to assess the performance of the modules and subsequently maximize efficiency and improve ROI.
So just as with so many aspects of PV systems available today, MLPE presents yet another choice for installers and homeowners as to which technology to opt for. Yet recent analysis from IHS Markit has shown that power optimizer solutions have begun to gain favor with PV installers over microinverters, with one of the main reasons being the flexibility of system design that they enable. For installers and customers alike, the benefits of flexible residential systems are obvious. Being able to offer a solution that they know can cope with the full range of requirements across the market means that they no longer need to purchase multiple solutions from different suppliers, which helps to significantly reduce operational costs.