The Sungrow SGRT-20 series are three-phase grid-tie inverters designed for commercial and larger residential systems, where reliability in grid operation is crucial, and high operational efficiency is expected. A standout feature is the dual MPPT - two independent power tracking channels simplify energy utilization even with different roof orientations or partial shading, minimizing losses without complicating the design.
In practice, this translates to excellent European efficiency, meaning truly high performance under typical operating conditions in Poland (variable sunlight and temperatures), resulting in greater annual energy yields. The series supports smart diagnostic functions (including IV curve scanning) and remote updates, reducing maintenance time and response periods. Monitoring is handled via iSolarCloud - through Wi-Fi or Ethernet (depending on configuration), with production monitoring and alarm visualization in the app. Built-in overvoltage protection and safety features for PV installations facilitate compliance with regulatory standards, while the standard warranty offers predictable costs throughout the system's lifecycle.
Ranking
Specifications
Pros and cons
The SG20RT achieves a European efficiency (EU-η) of 98.1% with a peak efficiency of 98.5%, placing the series among the top performers in the three-phase 20 kW string inverter segment. In Polish climate conditions-characterized by variable cloud cover and frequent partial-load operation-this translates into meaningfully higher annual energy yields compared to inverters rated at EU-η 97.0-97.5%.
Two independent MPPT channels allow the inverter to serve two roof sections with different orientations or shading profiles without cross-string mismatch losses. The wide MPPT input voltage range enables flexible PV string design and earlier morning production start at low irradiance levels.
A factory-integrated Arc Fault Circuit Interrupter (AFCI) and both DC- and AC-side Type II surge protection are standard across the series. In competing models from 2021-2023 (e.g., Fronius Symo), AFCI was either a paid option or unavailable, making this inclusion a meaningful cost reducer and simplifying compliance with insurance requirements.
The I-V curve scan feature enables remote diagnosis of module degradation and shading without an on-site service visit. The iSolarCloud platform (Wi-Fi/Ethernet) provides real-time production monitoring, fault alerts, and over-the-air firmware updates.
At 18 kg for a 20 kW unit (0.9 kg/kW), the specific weight outperforms the 2021 segment average of approximately 1.1-1.3 kg/kW for competing models. The IP65 protection rating permits outdoor mounting without an additional enclosure, reducing overall installation cost.
Production was discontinued in 2023 after only approximately two years on the market (launched 2021). Availability of new units and genuine spare parts is limited; for systems designed for a 25-30 year service life, this creates a risk of extended repair lead times and the need to source replacement components outside Sungrow's official distribution channel.
Alternatives
About the SGRT-20 series
These answers cover the whole series. Where a figure differs, the specification above is this model's own.