As you compare solar power companies, it seems they all recommend different types of solar equipment. One company says use panel “brand A” with a “brand B” inverter, while another company says, no, no, use panel “brand C” with a “brand D” inverter. System design suggestions can be very confusing, especially if these are terms that you’re hearing for the first time.
While most customers primarily focus on the solar photovoltaic (PV) panels when deciding on a solar system installation in Maui, the inverter is probably the most critical piece of the solar energy system.
In 2020, a solar company in California performed over 2,000 solar system repairs. When the data were tallied, they found the majority of these repairs were due to a faulty inverter.
Given this, while evaluating which inverter design you should use, it’s essential to consider the difference between string inverters and micro-inverters. Follow along to get a better understanding of the differences between the two most common solar inverter options and which may be best for your solar energy system.
What is an Inverter : Inverters are one of the most crucial parts of a solar power system because they convert direct current (DC) electricity generated by your solar panels (thanks to solar radiation) into usable alternating current (AC) energy that can be used by your household and the grid.
An inverter accomplishes the DC-to-AC conversion by switching the direction of a DC input back and forth very rapidly. As a result, a DC input becomes an AC output.
In a household solar system, your inverter performs several functions. In addition to converting your solar energy into AC power, it can monitor the system and provide a communication interface with computer networks.
Solar-plus–battery storage systems rely on advanced inverters to operate without any support from the grid in case of power outages. https://www.energy.gov/eere/solar/solar-integration-inverters-and-grid-services-basics
Types of Inverters: There are typically only two types of inverters that are installed as part of a solar system: microinverters or string inverters. Both types of inverters might be assisted by a gateway that controls how the solar system interacts with an attached battery storage system.
For example, an inverter can charge the battery directly over DC, such as with Generac PwrCell systems, or after a conversion to AC, such as with Tesla Powerwall systems.
String Inverters: String inverters are currently the most cost-effective inverter option available. String inverters work efficiently when solar panels are on a single plane without shading. For example, if you have 20 solar panels, a solar installation company will typically install the panels in 2 strings of 10 modules.
The solar panels are connected in series, and for home solar, the series of solar panels can reach up to 600 volts DC.
When a solar energy system is designed using a string inverter, the panels are linked together in a line, or “string”. This line moves the electrical current to a central “string” inverter. These connected solar panels are known as a “string array.” Solar panels on a solar string array are like a string of holiday lights. When using a string inverter, if one solar panel fails, the entire string of solar panels is impacted. A drop in your solar system’s performance can also happen if a solar panel’s output drops. This output drop can occur due to shade, a passing cloud, or some other unavoidable factor; essentially, your solar energy system’s performance adjusts down to match the lowest-performing module.
In simple terms, String inverters connect a set of panels in a string to one inverter. That inverter converts the power produced by the entire string to AC. Although cost-effective, this setup results in reduced power production on the string if any individual panel experiences issues.
SolarEdge string inverters are somewhat different as they incorporate what’s called an “optimizer”. The SolarEdge Power Optimizer is a DC/DC converter that is connected to each solar module, turning them into smart modules. These Power Optimizers claim to increase energy output from PV systems by constantly tracking the maximum power point (MPPT) of each module individually; however, as a string inverter, they are still limited by the functionality of a string inverter. The SolarEdge + optimizer system also allows for module-level monitoring.
Best Benefit of a String Inverter: The most significant benefit of a string inverter is the cost. String inverters are the lowest-cost inverter option available and are cheaper in terms of equipment. The string inverter typically comes with a ten (10) year manufacturer’s warranty.
Micro Inverters: Micro inverters are relatively new compared to string inverters; they have been around since the mid-90s, but only since about 2010 have they gained popularity in the solar industry. Unlike the string inverter, with micro inverters, there is an inverter mounted at every panel.
Solar micro inverters are rapidly gaining popularity, particularly in the United States’ residential solar market. Typically, microinverters are a more expensive option, but they have some unique advantages. Micro inverters convert the DC electricity at the panel level with no need for a separate inverter.
Micro inverters are connected in series and typically have a lower voltage. For solar energy systems for your home, the voltage for a micro inverter is generally 240 volts. This voltage is considerably lower than with a string inverter, which can be as high as 600 volts; therefore, safer. One of the significant advantages of microinverters is that they help mitigate the impact of shading. Micro inverters work essentially as a unique entity; there is no “bottleneck” when one panel is shaded. Another advantage of micro inverters is that a home’s solar energy system can have multiple panel orientations, such as south and west. Micro inverters, like Enphase Energy, come with an online performance monitoring system that allows you to monitor every single module’s performance visually.
Production monitoring is the best way to track the individual performance of every panel.
All in all, microinverters are smaller inverters placed below every solar panel. With a micro inverter, shading or damage to one panel will not affect the power that can be drawn from the others. On the negative side, micro inverter systems tend to be more expensive compared to string inverter systems.
Best Benefits of a Micro Inverter: The most significant benefit of a micro inverter is the ability to maximize your roof’s solar producing potential, especially with shaded or multiple roof orientation system designs. Since every solar panel and micro inverter acts independently from the other, you can easily add on to your system as your energy needs change over the years due to the ease of scalability and upgradeability with the micro inverter design. The micro inverter typically comes with a twenty-five (25) year warranty.
Micro inverter vs. String inverter + optimizer: The whole inverter+optimizer versus microinverter debate is pretty much a closed chapter as well. Microinverters have been proven to be far easier to install, troubleshoot, and replace than any inverter optimizer setup.
While the functionality of these two setups is designed to be the same, in our professional opinion, the overall performance and service experience are vastly different, with microinverters being superior… but that’s just our technical perspective.
The inverter+optimizer vs. micro inverter choice has now boiled down to a purely financial decision. Micro inverters cost an average of 10-15% more than string inverter system designs.
Inverter Maintenance: As mentioned in the opening, the majority of issues a solar energy system experiences are due to the inverter. This essential component tends to have more problems than the solar panels or any other part of the system, so it’s important to choose the right inverter for your needs.
In terms of repair and maintenance, micro inverters typically have a lower risk of failure since they have lower cooling needs compared to the string inverter solar system.
Best Inverter Option: If you want the latest technology for your home solar energy system, then you might consider the benefits of a microinverter system.
By utilizing microinverters for your system, this design incorporates one (1) inverter for each solar panel. This is a distinct advantage as individual solar panels can be isolated from the whole system. This isolation doesn’t hurt the overall performance of your solar system if there’s an issue with one of the inverters. Best of all, this system design typically includes a 25-year manufacturer’s warranty.
Best Company for Solar Panel Installation in Maui
How do you choose the solar system equipment that is best for your home needs? Contact the highest-rated solar installation company in Maui– WikiWiki Solar & Electric. Visit us at www.wikiwikisolar.com or by calling 808-244-9454. We would love the opportunity to provide a FREE analysis of the benefits and cost of solar. Contact us to see how much money you can save by switching to solar!
