Solar Inverter Comparison — Sol-Ark vs EG4 vs Sigenergy vs Growatt vs APsystems
The inverter is the most critical component in a solar-plus-storage system. This page compares every hybrid and microinverter we stock at Solwel so you can spec the right unit for your project.
Need help sizing or choosing? Call us at (346) 432-4228 or request a quote.
Hybrid Inverter Comparison
| Spec | Sol-Ark 12K | Sol-Ark 15K | EG4 12kPV | EG4 18kPV | EG4 FlexBOSS18 | EG4 FlexBOSS21 | Sigenergy SigenStor | Growatt 10kW | Growatt 11.4kW |
|---|---|---|---|---|---|---|---|---|---|
| Continuous Output | 12 kW | 15 kW | 12 kW | 18 kW | 13 kW | 16 kW | 3.8–11.5 kW | 10 kW | 11.4 kW |
| Phase | Split-phase | Split-phase | Split-phase | Split-phase | Split-phase | Split-phase | Split-phase | Single-phase | Single-phase |
| Off-Grid Capable | Yes | Yes | Yes | Yes | No | No | Yes | Yes | Yes |
| AC or DC Coupled | DC | DC | DC | DC | AC | AC | DC | DC | DC |
| Battery Compatibility | Open | Open | EG4 + third-party | EG4 + third-party | EG4 + third-party | EG4 + third-party | Sigenergy only | Open | Open |
| EV Charging | No | No | No | No | No | No | Yes (V2H) | No | No |
| Made in USA | Yes | Yes | No | No | No | No | No | No | No |
| UL 1741 SA | Yes | Yes | No | No | No | No | No | No | No |
| Warranty | 10 years | 10 years | 10 years | 10 years | 10 years | 10 years | 10 years | 10 years | 10 years |
Microinverter Comparison
| Spec | APsystems DS3-S | APsystems DS3-L | APsystems EZ1 | Hoymiles HMS-1600 |
|---|---|---|---|---|
| Rated Output | 640 VA | 768 VA | 800 VA | 1,600 VA |
| Panels per Unit | 2 | 2 | 2 | 4 |
| Max Panel Wattage | ~320W/channel | ~384W/channel | ~430W/channel | ~400W/channel |
| Plug-In Ready | No | No | Yes | No |
| Monitoring Gateway | ECU-R (separate) | ECU-R (separate) | Built-in WiFi/BT | DTU (separate) |
| Best For | Standard residential | High-wattage panels | DIY / small systems | Large panel arrays |
Which Inverter Is Right for Your Project?
Sol-Ark 12K & 15K — Best for Open Battery Compatibility, Off-Grid, U.S.-Made
Sol-Ark inverters are manufactured in San Antonio, TX and offer the widest open battery compatibility in the residential market — compatible with virtually every major LFP battery brand. The UL 1741 SA certification makes them one of the few residential inverters that meets advanced grid support requirements in California, Hawaii, and other states with strict utility interconnection rules. Best choice for installers who want flexibility and U.S.-based warranty support.
View Sol-Ark 12K → View Sol-Ark 15K →
EG4 12kPV, 18kPV, FlexBOSS18 & FlexBOSS21 — Best for Value, High Output, Retrofit
EG4 offers the most output per dollar in this comparison. The 18kPV at 18 kW is the highest-output single-phase hybrid inverter we carry — ideal for larger homes, homes with EV chargers, or installers who want headroom for load growth. The FlexBOSS series is AC-coupled, making it the easiest retrofit option for adding battery backup to an existing solar system without replacing the solar inverter.
View EG4 12kPV → View EG4 18kPV → View FlexBOSS18 → View FlexBOSS21 →
Sigenergy SigenStor — Best for EV Integration & All-in-One Systems
The SigenStor is the only inverter in this lineup with built-in bidirectional DC EV charging (V2H/V2G), making it the top choice for customers who want to integrate their electric vehicle into their home energy system. The closed ecosystem (Sigenergy batteries only) is the tradeoff for that integration.
Growatt 10kW & 11.4kW — Best for Budget-Conscious Residential with Rapid Shutdown
The Growatt XH series includes the Tigo RSS transmitter for NEC-compliant rapid shutdown out of the box — no separate purchase required. A solid option for standard residential installs where budget is a priority and the customer doesn't need off-grid capability or advanced grid support certification.
View Growatt 10kW → View Growatt 11.4kW →
APsystems & Hoymiles Microinverters — Best for Shading, Complex Rooftops, DIY
Microinverters eliminate string shading losses and provide panel-level monitoring — ideal for rooftops with chimneys, dormers, trees, or multiple orientations. The APsystems EZ1 is the only plug-in ready option for simplified DIY installations. The Hoymiles HMS-1600 handles four panels per unit, reducing component count on larger arrays.
View APsystems DS3-L → View APsystems DS3-S → View Hoymiles HMS-1600 →
Commercial Inverters
For commercial and industrial projects requiring three-phase output:
- Sol-Ark 30K-3P-208V — 30kW three-phase commercial hybrid inverter
- Sol-Ark 60K-3P-480V — 60kW three-phase commercial hybrid inverter
Talk to Our Team
We spec systems with installers and contractors every day. Call (346) 432-4228, email info@solwel.com, or submit a quote request for project-specific guidance.