Are Enphase Inverters Worth It?

Enphase microinverters are small devices that convert the direct current (DC) electricity from solar panels into alternating current (AC) electricity used in homes. Rather than one central inverter for the whole solar array, microinverters are installed at each panel. Key features of Enphase microinverters include maximum power point tracking for optimal solar energy harvest, grid forming technology to maintain grid stability, and monitoring and control through their Enlighten software.

Homeowners may consider Enphase microinverters for their solar installation because they offer higher efficiency, greater reliability, panel-level monitoring, and easier system expansion compared to string inverters. However, they also come at a higher upfront cost. This article examines the pros and cons of Enphase microinverters to help homeowners decide if they are worth the investment.

Efficiency

Enphase microinverters are generally more efficient than traditional string inverters. According to Enphase, their microinverters operate at peak efficiency of 96.5%, compared to string inverters which may operate around 95-96% efficiency at best [1]. This small difference can add up over the lifetime of a solar system.

Enphase’s distributed system architecture is a key factor in its efficiency gains. Because each solar panel has its own microinverter, the system can optimize production panel-by-panel. If one panel is shaded or damaged, it does not bring down the performance of the whole system. With a string inverter, the entire string of panels operates at the level of the lowest performing panel. By maximizing production from each individual panel, Enphase’s distributed approach improves overall efficiency compared to centralized string inverters [2].

Reliability

Enphase microinverters provide redundancy and resilience since each solar panel has its own inverter. If one fails, the rest of the system continues generating energy normally. This modular design means no single point of failure. Compare this to string inverters where if it fails, the whole system stops producing power (Enphase).

In addition, Enphase microinverters have excellent field reliability rates. Studies by installers show less than 0.1% failure over thousands of installs, much better than string inverters (Reddit). Real world reliability data from Enphase shows a failure rate of only 1 in 3,000 units over many years of operation (1komma5grad). The distributed nature and solid state design contribute to very high reliability compared to string inverters.

Monitoring

One of the standout features of Enphase inverters is their advanced monitoring capabilities thanks to the Enphase Envoy system. The Envoy is a communications gateway that transmits data about your solar system’s performance over the internet to Enphase’s monitoring platform, MyEnlighten.

Through the MyEnlighten dashboard or Enphase mobile app, homeowners can easily monitor their system’s production and consumption in real time. You can view insights like how much energy your system has generated today or this month, your current self-consumption rate, and more. The Enphase app even allows you to control your smart devices and appliances to optimize self-consumption if you have Enphase’s smart switch.

This level of visibility into your system’s performance is incredibly useful for homeowners. You’ll know right away if an issue arises, like an inverter malfunctioning. And you’ll be able to make informed decisions about your home’s energy use and storage needs based on your actual solar data. Overall, Enphase’s monitoring provides unmatched visibility and control compared to string inverter systems.

For more details, see Enphase’s page on the Envoy system:https://www4.enphase.com/en-in/support/what-envoy and their solar monitoring app: https://enphase.com/homeowners/enphase-app

Expandability

One of the key advantages of Enphase microinverters is how easy it is to expand the system by adding more solar panels. With an Enphase system, each solar panel connects to its own microinverter, so adding more panels is as simple as mounting them on the roof and plugging them into the existing Envoy gateway.

This modular approach stands in stark contrast to traditional string inverter systems. With string inverters, all the solar panels are wired together into a single circuit. Expanding a string inverter system often requires purchasing a whole new inverter that can handle the increased number of panels. There are also limitations on how many panels can be added before the inverter needs to be replaced.

Enphase systems have no such restrictions. You can start small with just a few panels and microinverters, and add more down the road as needed. Enphase even provides guidance on expanding DIY. The Enphase Q Aggregator can support up to 59 IQ Series microinverters, while the Envoy can support several hundred. This modular and scalable approach makes Enphase systems extremely flexible and future-proof.

Shade Tolerance

One of the key advantages of Enphase microinverters over traditional string inverters is their superior shade tolerance. Enphase systems perform significantly better than string inverters when panels are partially shaded. That’s because each Enphase panel has its own microinverter, so the rest of the system is unaffected if one panel is shaded.

Independent tests have shown that Enphase system output can be 20% higher than a string inverter when one panel is slightly shaded (source). The difference is even more dramatic as shading increases. Enphase estimates their systems can produce up to 40% more power than string inverters under heavy shading conditions. This is a major advantage for installs on roofs with uneven shading.

With a string inverter, the whole string of panels operates at the level of the most shaded panel. So even a small amount of shade can drastically reduce system production. Enphase’s panel-level optimization ensures maximum output regardless of uneven shading across the roof.

Warranty

One of the key benefits of Enphase microinverters is their excellent warranty coverage. Enphase offers a 25-year limited warranty on both their microinverters and optional Envoy communications gateway, which is one of the longest in the industry (Enphase, n.d.). This contrasts with the typical 10-12 year warranty provided by string inverter manufacturers like SMA, SolarEdge and Fronius.

The generous 25-year warranty reflects Enphase’s confidence in the reliability and longevity of their microinverter systems. It covers repair, replacement or reimbursement in the event of a product defect or failure during normal use, with some exclusions for things like improper installation (Enphase, 2021).

Having a longer warranty period provides valuable peace of mind for homeowners and installers alike. If any individual microinverter fails after the typical string inverter warranty has ended, Enphase will still cover the replacement cost under their warranty. This can represent significant long-term savings compared to a string system where the entire inverter would need replacing out-of-pocket after 10-12 years.

Cost

When examining the cost of an Enphase microinverter system, it’s important to consider both the upfront costs as well as the total cost of ownership over the system’s lifetime, which is usually around 20 years. Enphase microinverter systems do tend to cost more upfront compared to string inverter systems. According to 1komma5grad, a 6.6kW Enphase system will cost about $1500 more than a comparably sized SolarEdge string inverter system. For a 10kW system, the price difference is also about $1500.

However, Enphase systems can save money in the long run due to their high reliability and system monitoring capabilities. Fewer component failures means lower lifetime maintenance and replacement costs. And with remote monitoring, issues can often be identified and resolved before they lead to system downtime and lost production. So while Enphase systems have a higher upfront cost, the total 20 year cost of ownership can end up being lower compared to string inverters when accounting for maintenance savings over that timeframe.

Sources:

https://1komma5grad.com/au/blog/enphase-price-vs-solaredge-a-standard-system

Resale Value

Enphase microinverter systems tend to retain value better for home resale compared to string inverter systems. According to discussions on Reddit, Enphase used to charge a transfer fee of $399 when someone bought a house with an existing Enphase system. This fee transfers the 25-year warranty to the new homeowner. Now the transfer fee is $200 (https://www.reddit.com/r/solar/comments/14wq4l6/does_enphase_really_charge_200_usd_if_someone/). So while there is a cost to transfer, the Enphase warranty adds value. String inverters typically only come with 10-12 year warranties that are not transferable.

When selling a home, having an Enphase system demonstrates the solar investment is high-quality and built to last. The monitoring also allows home buyers to see the system’s performance. Enphase products like the IQ7 microinverters and Envoy communications gateway can be resold on sites like eBay if removed during a system upgrade (https://www.ebay.com/b/Enphase/bn_21824395). Overall, the Enphase system retains value on resale that can help home sellers recoup the investment.

Conclusion

When considering whether Enphase microinverters are worth the investment, there are several key pros and cons to weigh. On the pro side, Enphase systems offer high efficiency rates, excellent reliability and durability, comprehensive monitoring capabilities, easy system expandability, advanced shade tolerance, and long warranties. The key downsides are the higher upfront cost compared to string inverters and potentially lower resale value.

Overall, for most homeowners, the benefits of Enphase microinverter systems outweigh the downsides. The efficiency, reliability, monitoring, and future expandability make Enphase a great choice for those looking to maximize solar production and have peace of mind about system performance and longevity. While the upfront cost is higher, over the life of the system, an Enphase system is likely to pay for itself through increased energy production and reduced maintenance costs. For those prioritizing advanced solar capabilities over lowest initial cost, Enphase microinverters are typically worth the premium investment.