When designing a solar system, customers often focus on the best solar panels. While that’s an important decision, they can overlook another crucial piece of equipment: the inverter.
Solar inverters convert the DC energy your panels produce into AC electricity your business uses. They’re also often the first component that’s replaced, so choosing a good model is important.
String Inverters VS Microinvters: What’s the Best Type of Commercial Solar Inverters?
There are three inverter options for your business’s solar array: string inverters, microinverters, and string inverters with power optimizers.
Each has its advantages — and what’s best comes down to your specific goals. We typically recommend string inverters with or without power optimizers for commercial solar panel systems. However, here are all the options.
String Inverters
String inverters are the most common for ground mounts, thanks to their solid performance and affordability. Each inverter is connected to several groups, or strings, of solar panels.
The size of your solar array will dictate how many inverters you’ll need, ranging from one to a dozen or more. They’ll typically be mounted along a wall in a protected area from the weather.
One string inverter converts energy for several solar panels. When one panel’s production is reduced, whether from shade, damage, or something else, it’ll impact the production of all other panels in that string.
However, even with loss from shading, string inverters are often the most economical for larger commercial solar systems.
Microinverters
Microinverters attach to the underside of each solar panel in your system. Compared to string inverters, there’s more equipment, and they take longer to install, leading to higher costs. Microinverters can be more challenging to maintain as they’re spread across the panels and may require roof access.
The main benefit is module-level optimization. Each panel produces as much energy as possible, unlike string inverters, where the least-producing panel sets the production for all others in the string.
That said, the cost of microinverters typically won’t make up for gains in production on commercial-sized systems.
String Inverters with Power Optimizers
The third option is a hybrid. It utilizes string inverters but also integrates module-level optimization through power optimizers, Power optimizers are small boxes installed on every solar panel that allows each panel to produce its maximum energy.
While string inverters + power optimizers cost more than string inverters alone, they are more affordable than microinverters. They may be good for commercial systems impacted by shading, if space constraints make maximizing efficiency imperative, or on rooftops where rapid shutdown is required.
Which Solar Inverter Brands are Best for Commercial Solar?
With the basics covered, we can now dive into the specifics. Here are our top picks for commercial solar inverters:
SolarEdge
Product Offerings
SolarEdge manufactures string inverters that integrate with power optimizers, giving your commercial system module-level optimization for increased productivity.
The inverters will be mounted to a wall, and optimizers will be installed on each panel.
Their single inverters come in 17.3k and 40k sizes. Each will have a dimension of 32” x 12.5” x 12”. Your system may require multiple, depending on how many panels are installed. They also offer multiple inverter clusters at 50k and 120k. One unit is 14” x 22” x 12” and three units are 22” x 13” x 11”.
Warranties
SolarEdge inverters have 12-year warranties that can be extended to 20 years, and power optimizers have a 25-year warranty.
Cost
SolarEdge won’t be the cheapest option, but it’s a dependable product at a fair price. The added cost for optimizers can be justified if maximizing efficiency is important for your system.
SMA
Product Offerings
SMA produces string inverters without module-level optimization. We like their Core 1 model for commercial systems, which measures 29” x 25” x 22”. These are for roof-mounted systems on flat roofs or installed on pad-mounts.
They also feature SMA ShadeFix, which helps reduce production lost to shading.
Warranties
Your SMA inverter will be covered by a 10-year warranty, which you can extend by five or ten years.
Cost
An SMA string inverter system will most likely be the most economical option for a commercial solar inverter while still delivering on performance and durability.
Chint Power Systems (CPS)
Product Offerings
CPS is another string inverter manufacturer that delivers on value. These wall-mounted inverters measure 40” x 24” x 10”.
Warranties
Most CPS inverters are backed by a ten-year warranty. Their larger models (1500 Vdc) are backed by five-year warranties.
Cost
CPS inverters offer a great product at a fair price. Compared to SolarEdge and SMA, CPS may be the most economical option.
Tips for Choosing the Best Inverters for Commercial Solar Systems
Here are a few additional things to look for when evaluating your inverter options:
- Financial stability of the company
- Customer reviews & experiences
- Whether it’s approved by your utility
- Warranties of at least ten years
- CEC efficiency of at least 97% (most are 98%+)
- Equipped with Rapid Shutdown (if required)
- Your preferred mounting location (roof vs. wall vs. pad-mounted)
- Ease of installation
- Ease of monitoring and what data they provide
Keep in mind your solar installer should be there to guide you through this step, navigating the technical minutia and ensuring you end up with an inverter setup that’s ideal for your commercial solar investment.
If you’re not ready to speak with one of our team members, the next best thing to do is download our solar buying guide, visit our other educational blog posts, or watch our short, to-the-point videos.
