The SolarBridge Microinverter performs the same DC to AC conversion and Maximum Power Point Tracking (MPPT) function as a central inverter, but at the module level. Unlike other microinverters, the SolarBridge Microinverter is designed to integrate directly to the back of a PV module, which significantly reduces installation cost and complexity. The SolarBridge Microinverter is covered by eight patents and has been recognized by industry experts as a novel approach to highly reliable dc-ac conversion. The key advantages of the SolarBridge Microinverter include the following:
Reliability
Competitive microinverters are simply scaled-down versions of larger central inverters. They have the same topologies and components and are designed to last only 5 to 15 years. Because solar modules typically come with a 25 year warranty, competitive microinverters need to be replaced once or twice during the life of the solar module.
SolarBridge Technologies believes the microinverter should last as long (or longer) than the solar module. The SolarBridge microinverter was designed from the ground up, utilizing patented technologies to optimize reliability. The SolarBridge Microinverter’s innovative architecture avoids failure prone components, such as electrolytic capacitors, optoisolators, fans, displays, etc… which limit reliability in central inverters and competing microinverters. It also has one less conversion stage. As a result of its ultra-reliable architecture and high MTBF, the SolarBridge Microinverter will be covered by a 25 year warranty, matching that of the module.
Maximum Energy Production
The SolarBridge Microinverter performs Maximum Power Point Tracking (MPPT) at the module level.
This means that the power output from each module is always maximized, even in shading or soiling situations. Each module now operates independently from all of the other modules in the system. One or more underperforming modules have no effect on the other modules in the system. Mismatch between modules in a string is no longer an issue. Distributing the MPPT function to each module means that you are always getting the maximum energy harvest from each module, and therefore the entire system. The SolarBridge Microinverter provides a 5% to 25% energy production advantage over a centralized inverter.
With the SolarBridge Microinverter, there is no single point of failure. In the rare situation where a failure occurs, the power loss is limited to one module, say 200W, and the rest of the system will continue to operate normally. The failed unit can be replaced whenever it is convenient, such as the next time the modules are cleaned, and the expense of one or more incremental truck rolls for maintenance is avoided. If a central inverter fails, the power loss is typically between 3kW and 500kW, depending on the size of the installation, and the situation becomes a crisis.
Lower Upfront and Operational Costs
The SolarBridge Microinverter reduces upfront costs in 2 ways. First, the design process is simpler, as designers are no longer constrained by string designs or the need to design systems into coplanar arrays. Second, installation costs are also significantly reduced. Because the SolarBridge Microinverter ships attached to the back of a module as part of an ACPV system, there is no need to install either a central inverter or a numerous microinverters to the racking system. This is a huge time and cost savings. When the SolarBridge is mounted to the back of a module, there is no exposed DC wiring and the output from the module is AC. This means that several components found in traditional systems such as DC wiring, DC circuit breakers, and DC disconnect switches are eliminated, further reducing costs and improving reliability.
The SolarBridge Microinverter also reduces operational costs. The long lifetime and 25 year warranty means that the system owner does not need to replace the inverter once or twice during the life of the module. This results in a big Levelized Cost of Energy (LCOE) benefit for the SolarBridge Microinverter
Flexibility
If a module fails in a traditional system utilizing a central inverter, it needs to be replaced with a module having the exact same voltage and current characteristics (typically the same model). Module manufacturers have two options: they can either perform costly rework on the failed module (typically not done) or they can stock their warehouses with a supply of modules from all previous generations … a costly and undesirable solution. With the SolarBridge Microinverter, this issue goes away. Current generation panels with the highest efficiency and lowest cost can be used to replace failed modules from a previous generation. Because the AC outputs from the ACPV modules are paralleled, mixing module types and technologies is now possible.
Safety
The module output in traditional systems utilizing a central inverter can be up to 600V DC in the United States and up to 1000V DC in Europe. These can be hazardous voltage levels for installers, maintenance personnel, and emergency responders. In contrast, the output from modules attached to the SolarBridge Microinverter will be at much safer levels (between 200V and 240V AC).