Fronius Reserva 6.3 vs SAX Power Home PLUS 7,7 kWh


Usable capacity: Fronius Reserva 6.3 6.31 kWh, SAX Power Home PLUS 7,7 kWh 7 kWh. Both models win equally often (3 of 8 points).
Who wins where
- Fronius Reserva 6.3
- SAX Power Home PLUS 7,7 kWh
Biggest differences
| Fact | Reserva 6.3 | Home PLUS 7,7 kWh |
|---|---|---|
| Min. operating temperature | -20 °C | 5 °C |
| Charge power (continuous) | 6.55 kW | 1.4 kW |
| Discharge power (continuous) | 6.55 kW | 4.6 kW |
| Weight | 86.5 kg | 72 kg |
| Nominal capacity | 6.68 kWh | 7.68 kWh |
| Usable capacity | 6.31 kWh | 7 kWh |
Score per area = position (0–100) relative to all 130 models in this category; higher is better.
| Technical specifications | FroniusReserva 6.3 | SAX PowerHome PLUS 7,7 kWh |
|---|---|---|
| General | ||
| Cell chemistry | LFP 1 | LFP 2 |
| Performance | ||
| Usable capacity | 6.31 kWh 1 | 7 kWh ✓ 2 |
| Nominal capacity | 6.68 kWh 3 | 7.68 kWh ✓ 2 |
| Expandable up to | – | 23 kWh 2 |
| Charge power (continuous) | 6.55 kW ✓ 1 | 1.4 kW 2 |
| Discharge power (continuous) | 6.55 kW ✓ 1 | 4.6 kW 2 |
| Efficiency | ||
| Round-trip efficiency | 95 % 1 | – |
| Electrical | ||
| Coupling | DC-coupled 1 | AC-coupled 2 |
| Phases | – | 1 2 |
| Backup power | Yes 1 | Yes 2 |
| Dimensions & weight | ||
| IP rating | IP65 1 | – |
| Min. operating temperature | -20 °C ✓ 1 | 5 °C 2 |
| Width | 772 mm 1 | 620 mm 2 |
| Height | 890 mm 1 | 620 mm 2 |
| Depth | 176 mm 1 | 250 mm 2 |
| Weight | 86.5 kg 1 | 72 kg ✓ 2 |
| Warranty & lifespan | ||
| Warranted cycles | 6,000 1 | – |
| Warranty | 10 years 1 | 10 years 2 |
Sources
- The Fronius storage solution, V09 Sep 2026 — Fronius International GmbH · accessed 29 Sept 2026
- AC-SPEICHERSYSTEME DATENBLATT, zonder versienummer — SAX Power · accessed 29 Sept 2026
- CEC approved solar batteries (Australia) — Clean Energy Regulator (Australian Government), CC BY 4.0 · accessed 29 Sept 2026