Enphase vs SolarEdge: which inverter system is best?
80% of the home solar inverter market is dominated by Enphase and SolarEdge. Here’s a side-by-side comparison.
In a home solar installation, the inverter plays the critical role of turning the direct current (DC) from the solar panels into alternating current (AC) so all the appliances at home can use electricity.
Broadly speaking, there are three types of inverter systems:
Microinverters
String inverters; Centralized
Power optimizers System; String inverters + Power optimizers
Enphase and SolarEdge collectively now own 80% of the residential solar inverter market. That’s a huge chunk of market share, so if you’re thinking about going solar, upgrading an existing system, or replacing a failed inverter, it’s a good idea to get familiar with the product lineups of these two companies.
Enphase Micro-inverters
Since 2006, the Northern California company focuses on micro-inverters, and does not have any string inverters in their product lineup. With a micro-inverter-based system, every solar panel is coupled with one small inverter that is mounted on the back of the panel. This means that the DC-to-AC conversion happens right at the back of the panel, so the unit must be durable to withstand the outdoor elements for a few decades. Their inverters make the solar system more productive, more reliable, smart, and safe for customers to use.
SolarEdge Inverters
The company with headquarters in Israel was founded in 2006 and offers a wide range of inverters for residential and commercial use. SolarEdge offers central inverters that pair with power optimizers. Their inverter for residential use is the single phase HD-Wave inverter.
With the SolarEdge system, there is a central inverter that is installed in your basement, garage, or on an outdoor wall at ground level. It handles the DC-to-AC conversion for all the panels in the array and the power optimizer unit that is bolted onto the back of each solar panel.
What happens if SolarEdge inverter or Enphase microinverter malfunctions?
Both offer a technology that isolates the performance and enables the monitoring of each individual panel, their modes of failure are quite different.
- SolarEdge failure mode: Most of the failures we noticed in SolarEdge installations happen at the inverter level which means that the entire system will cease to produce power until the inverter is fixed or replaced.
- Enhase Micro-inverters failure mode: If one microinverter malfunctions, the other microinverters will keep producing power, making it more advantageous than SolarEdge.
Scalability
SolarEdge’s scalability is limited in comparison to Enphase microinverters. SolarEdge systems are limited to the size of the central inverter which can intake a certain number of solar panels, Enphase microinverters have higher flexibility to scale by simply adding solar panels with compatible microinverters.
Scalability matters to clients who project an increase in their future power demand in case of adding an electric vehicle, or adding a battery backup system for example. Theoretically, you can add an unlimited number of panels (some modifications may be required of course) when you have a microinverter system but you may have to change the central inverter if you want to increase the number of solar panels.
Warranty Comparison
With any product, the length of a warranty gives a consumer a good idea of how long they can approximately expect a product to last.
Enphase microinverters have a 25 year product warranty, which is the longest in the industry. While SolarEdge power optimizers also have a 25 year warranty, the central inverter comes with only a 12 year warranty. SolarEdge offers 20 and 25 year warranty extensions that you can upgrade for a an additional cost.
In other words, 12 years is the expected lifespan of a central inverter. This means that you should expect to replace your inverter at least once during the expected 25 year lifespan of your solar panels. Be sure to include this factor when comparing the price of a string inverter or power optimizer-based system to microinverters.
Cost Comparison
In general, a microinverter-based system will be the most expensive option. A power optimizer-based system will be somewhat cheaper, and a string inverter will be the least expensive.
Monitoring Systems
Both Enphase and SolarEdge give you panel-level monitoring that is available from the web or a smartphone app. They’ll tell you how much power you generate in real time, and let you generate reports on how many kilowatt-hours of electricity your system has generated on any day, week, month, or year.
Both systems also let you see how much power each solar panel generates, which is a great feature to help you monitor the health of your system and to know when one panel might be having a problem.
One thing to note: with Enphase, the monitoring system is provided by a separate product called IQ Envoy. It communicates over Wi-Fi or cellular to send data to Enphase servers. If you go with Enphase, be sure to ask your installer about this monitoring functionality and get pricing for the IQ Envoy as a separate line item on your invoice. With the SolarEdge HD-Wave inverter, the monitoring system is built into the device.
Home Battery add-on
With growing interest in home batteries, especially with planned blackouts in California becoming commonplace, as well as the new TOU rates utilities are moving to, more and more companies are getting into the battery storage market. The new Enphase Encharge (10.1 kWh) batteries are becoming the market leader as an all-in-one solution that integrates well with Enphase micro-inverters and its software.
In other hand, if you have SolarEdge system, the only available option is the LG Chem RESU battery (10 kWh).
Note that both these are smaller than the 14 kWh Tesla Powerwall. The biggest issue with the Tesla Powerwall is the long waiting list that ranges from 6 to 9 months for delivery.
Enphase vs SolarEdge: which should you choose?
If you have to install solar panels in your home with partial shading, solar panels mounted on multiple roof segments, or the desire for panel-level monitoring, then both Enphase and SolarEdge inverters can be a great solution to make sure that you get the maximum electricity out of your solar energy system.
In addition, if you think you might want to expand your system in the future – such as to supply electricity for an electric car – then Enphase microinverters offer better expansion flexibility than either power optimizer or string inverter-based systems.
Which should you choose? While it’s likely that Enphase will cost you slightly more up front, if I had to choose between the two, I would go with Enphase.
The reason comes down to reliability. While Enphase products general “word on the street” from installers is that there are fewer in-field replacements and dead-on-arrival units. In addition, Enphase has done a good job on the customer side by offering their upgrade program to owners with early generation microinverters. Finally, Enphase inverters come with a full 25 year warranty.
SolarEdge power optimizers can also be a good choice for tricky rooftops with shading issues, but there are some reliability concerns with their latest products. Because it’s a public company, these issues are discussed in the open. In a recent earnings call, the Acting SolarEdge CEO Zvi Lando admitted that the company has been experiencing an increased number of warranty claims on their single phase inverter series (the type used for home installations).
…in recent months, we experienced an increased number of single phase inverter failures and heightened call center activity. This was due to a combination of two reasons. First, releasing new products and capability is typically characterized by an initial period of stabilization until manufacturing processes are fully mature. Second, during this period due to our growth in market share and increased shipments, there was a significant increase of new installers and accounts using our technology for the first time, and there is a short learning curve for them as well.
Whatever the case, the product failures are real, and have been mentioned in earnings calls in both 2018 and 2019.
Even though product failures are covered by warranty, the labor cost of a replacement isn’t covered by warranty. It’s an expense you definitely want to avoid.