If you’re thinking about getting solar on your home, you may want to research what the best solar panel is, but in my opinion, it’s even more important to choose the right inverter. While there are subtle advantages and disadvantages to different solar panels, bad inverters are the biggest cause of problems with solar systems. Having the right inverter can make a huge difference in the long-term performance of a solar system.
(If you’re interested in getting solar on your home in Virginia, read our complete guide to residential solar in VA!)
Inverters take DC energy from the solar panels and convert it into AC electricity that your home can use. It’s often the most complicated piece of equipment in a solar system and usually the second most expensive, after the panels themselves. They are also the most likely piece of equipment to cause a major loss of production if they fail.
There are a lot of technical specs that can be dug into with inverters, like CEC efficiency, power input & output, and more, but from installing solar for over a decade, the part that matters most to me is reliability.
Are Microinverters Better Than String Inverters?
There are essentially two types of inverters on the market: string inverters and microinverters. Which one is better depends on the site and the system design. In general, we recommend string inverters for ground-mounted systems, mainly due to current code requirements. Certain brands of string inverters, like SMA and Fronius, can be extremely reliable and offer performance comparable to microinverters. Here are some general rules about when a particular inverter is best:
Microinverters are best for:
- Rooftop installations
- Sites with shading considerations
- Multiple different roof orientations
String inverters are best for:
- Ground mounts
- Sites with no shading
- Carports / open barns
Due to changes in the electric code, most string inverters cannot be used on rooftop residential installations (in Virginia, at least). If they are, they typically require additional electrical devices to be installed behind each panel, eliminating a lot of the potential cost savings and adding more points of failure.
While the argument against microinverters is that they add points of failure, they do eliminate a “single point of failure,” which is extremely important. When a string inverter fails, NO solar is produced. When a microinverter fails, just one panel stops producing. It’s a lot easier to wait for maintenance if you have 29/30 panels working versus 0/30 panels working.
What Brand of Inverter is the Most Reliable?
This is our opinion, so take it with a grain of salt. We’ve worked with SMA, Fronius, SolarEdge, GoodWe, Enphase, and many other inverter brands over the years. Most major inverter companies have experienced some widespread failures at some point in their history—
Enphase almost went under from failures of their early micros, Fronius had major issues with their IG Plus line, and we were the unlucky recipients of a bad batch of SMA SunnyBoys back in 2018. We also experienced what I would describe as a massive number of SolarEdge inverter failures, which caused us to stop installing their inverters and pivot to Enphase back in 2021.
While there is no guarantee that a system will be problem-free forever, we have seen the best reliability from Enphase and Fronius products. Enphase publishes a 0.05% failure rate on their microinverters, which is 1 out of 2,000. They are also one of the only inverter companies that even publishes their failure rate, which speaks volumes.They come at a higher price-point than most other inverters, but if you take a trip through Reddit, you’ll see most folks agree they are worth it.
There are more competitors entering the microinverter market, like Hoymiles and APSystems, but early reports from other installers have not given us the confidence to try them. Neither company has published failure rates, and APSystems comes with a 10-year warranty by default (15-years less than Enphase).
What Inverters Integrate Best with Solar Batteries?
In 2025, it’s much easier to integrate solar systems and solar batteries than ever before. Batteries from FranklinWH are designed to work with any inverter, and Enphase has their own battery backup system as well. So if you want a string inverter on your ground-mount, or have an existing solar system from a few years ago– don’t worry! It’s essentially not an issue any more, and you can easily add solar battery backup.
If you have a roof-mounted system, Enphase is our pick here. It gives you the option of pairing with a FranklinWH aPower 2, but you can also keep the entire solar system within the Enphase ecosystem with the Enphase IQ battery system.
What about V2H bidirectional charging?
If you are holding out for Vehicle-to-Home bidirectional charging (we are too), then Enphase & Tesla are both promising options. Enphase has announced a bidirectional charger that should be available in 2025, and Tesla offers bidirectional charging through their “Powershare” platform. It is currently available on the Cybertruck, but may be expanded to other cars in the future. If you aren’t planning on buying a Tesla, then Enphase is likely to offer more options down the road.
