The GoodWe SDT G3 series are three-phase grid-tie (string) inverters designed for demanding rooftop installations - from homes with higher power allocations to small commercial properties. What distinguishes them is their quiet operation, compact design, and housing with a IP66 protection rating, which facilitates installation even in more challenging environmental conditions. Two independent MPPT inputs allow for better energy utilization when modules are in different orientations or when parts of the roof are intermittently shaded - the inverter optimizes performance independently for each string, improving yield in real-world conditions.
High efficiency (including European efficiency) means fewer losses during conversion and more stable energy production under typical Polish operating conditions. The SDT G3 supports intelligent energy management, including export limits and consumption monitoring once a compatible meter is installed. Available communication and monitoring options (including WiFi or LAN/Ethernet) feature monitoring in the SEMS app. This is the series for users who expect modern diagnostics and safety solutions, such as optional AFCI and type II SPDs.
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Models with a power output of 4-30 kW achieve a maximum efficiency of 98.6%, while models with a power output of 25-40 kW achieve even 98.8%. The European efficiency level of approximately 98.0% represents actual conversion losses below 2% in typical Polish solar profiles, which translates to a higher annual yield compared to devices from the previous generation of SDT G2.
The ability to connect a DC string with power up to 150% of its nominal AC power allows the designer to use more modules without increasing the inverter's power, which shortens the return on investment by better filling the production curve during morning and evening hours. A maximum input current of 22 A per string allows for the use of high-current N-type modules.
GoodWe is featured on BloombergNEF's Tier 1 Power Inverter Manufacturer list for Q2 2025, confirming its acceptance by financial institutions that fund PV projects with non-recourse financing. With over 100 GW of installed capacity globally (as of Q1 2025), this demonstrates the maturity of its supply chain and the availability of technical support.
When registering a device on the SEMS portal (requirement: production after July 2020 and registration after January 1, 2021), the factory warranty is automatically extended to 10 years at no cost. Competitors such as SMA and Fronius typically offer a standard warranty of 5-7 years, with an additional cost for extending it to 10 years.
The built-in SPD Type II surge protection and AFCI (arc fault detection on the DC side with alarm and circuit interruption) options enhance fire safety - features that are increasingly required by building insurers and institutional investors in Poland.
The SDT G3 is a purely grid-tied inverter - it does not support energy storage or EPS (Emergency Power Supply) functions. Given the increasing interest from prosumers in energy storage, adding a battery to the system later would require replacing the inverter with a hybrid model (e.g., from the GoodWe ET/EH series), which would incur additional labor and equipment costs.
Full diagnostics and remote monitoring rely on the SEMS Portal platform (GoodWe), which means that the device's entire lifecycle is dependent on the manufacturer's cloud infrastructure. In the event of a lack of internet access or a service outage, monitoring becomes unavailable - unlike solutions with a local server (e.g., SMA Home Manager).
Alternatives
About the SDT G3 series
These answers cover the whole series. Where a figure differs, the specification above is this model's own.