3/9/2026 / Wels
Product

Excellent results for Fronius Reserva & GEN24 Plus in Energy Storage Inspection

Fronius once again achieved an excellent result in the 2026 Energy Storage Inspection conducted by HTW Berlin in cooperation with aquu. For the first time, a completely in-house system was submitted ­— consisting of the Fronius Symo GEN24 Plus 10.0 SC and the Fronius Reserva 12.6. The setup impressed and achieved a System Performance Index (SPI) of 95.3%, which corresponds to the highest efficiency class "A".
Fronius Symo GEN24 and Reserva with Energy Storage Inspection seal

Optimized system dynamics
The test result underlines the technical quality of the Fronius energy storage system and its perfect compatibility with the Fronius GEN24 inverter series. Compared to previous years, we have significantly improved the response time of the Fronius system. It now reacts much faster to load changes and thus uses PV energy even more efficiently in everyday use.

Fronius Reserva in practical testing
With the Reserva, Fronius presented its own modular high-voltage storage system for inspection for the first time. The storage system impressed with numerous strengths:

  • Flexible scalability up to 15.8 kWh per tower, up to four towers in parallel
  • High charging and discharging power for optimal use of short periods of sunshine
  • Quick setup thanks to wireless plug-and-play concept
  • Seamless integration into Fronius digital tools
  • Versatile mounting options (–20 to +55 °C, IP65)

Close integration into the Fronius system ensures precise, stable, and efficient control of energy flows — both in simulated everyday conditions in testing and in real-world operation.

Strong backup power performance
Together with the Fronius Reserva, the GEN24 Plus provides a complete backup power supply for the entire house (Full Backup). Depending on the configuration, the switchover is automatic or manual.

Nico Orth, Head of Energy Storage Inspection at HTW Berlin, confirms that the system is extremely reliable: "When a battery storage system is connected to the GEN24 Plus, it is possible to provide a complete backup power supply for the entire house. This means that even three-phase consumers can be supplied with energy in the event of a power failure."

In addition, the Fronius ecosystem offers a wide range of backup options, from the PV Point as a basic backup power supply to a Full Backup with a battery storage system. This makes the Fronius system one of the most versatile and practical backup power solutions on the market.

Intelligent optimization with Energy Cost Assistant
Another strength of the Fronius complete system is the AI-based Fronius Energy Cost Assistant. It complements the overall system with predictive and highly profitable control of energy flows. The Energy Cost Assistant continuously analyzes the expected PV yield, current energy consumption in the household, and the respective electricity price. Based on this information it automatically adjusts the storage strategy.

This means that energy flows are not only controlled in a technically optimal way, but also prioritized in a manner that is also economically profitable. Users can thus get the most out of their storage system and reduce their electricity costs — without any additional hardware.

Back to overview