Fortress Power Envy 10K
For grid-tied homes that want an outdoor hybrid with export, backup and US-based support at a lower price than the Envy True 12.
Wind & Sun $3,899$3,899
The Fortress Power Envy 10K is the better hybrid solar inverter overall, rated 4.1 to 3.6. The Fortress Power Envy 10K leads on value and solar input. The Fortress Power Envy 10K costs $1,529.57 less ($3,899 vs $5,428.57).
Sol-Ark 12K-2P
For installers matching existing 12K systems or homes that want a proven Sol-Ark on a critical-loads panel. Most new buyers get more for less from the Limitless 12K-2P-LL.
altE $5,428.57$5,428.57
Prices were last checked October 23, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Which should you buy?
- Choose the Fortress Power Envy 10K for value ($390 per kW of continuous output vs $603 per kW of continuous output) and solar input (15,000 W of panels, 600 V max, 2 MPPTs vs 12,000 W of panels, 500 V max, 2 MPPTs).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every 120/240 V split-phase hybrid solar inverter; a clear win is highlighted. How we rank explains each one.
| Factor weight | Fortress Power Envy 10K | Sol-Ark 12K-2P |
|---|---|---|
| Overall rating | 4.1/5 | 3.6/5 |
| Value 30% | 62 $390 per kW of continuous output | 19 $603 per kW of continuous output |
| Solar input 20% | 68 15,000 W of panels, 600 V max, 2 MPPTs | 59 12,000 W of panels, 500 V max, 2 MPPTs |
| Efficiency 20% | 63 94% peak efficiency, 70 W idle | 66 60 W idle |
| Features 15% | 100 UL 1741 listed, Wi-Fi app, parallel stacking, grid sell-back, generator input, battery communication | 95 UL 1741 listed, Wi-Fi app, parallel stacking, grid sell-back, battery communication |
| Warranty 15% | 100 10-year warranty | 100 10-year warranty |
Specifications
| Fortress Power Envy 10K | Sol-Ark 12K-2P | |
|---|---|---|
| Output | ||
| Output voltage | 120/240 V split-phase | 120/240 V split-phase |
| Continuous output | 10,000 W | 9,000 W |
| Surge | 20,000 W | 16,000 W |
| Peak efficiency | 94% | - |
| Max efficiency | - | 97.5% |
| CEC efficiency | 96.5% | 96.5% |
| Idle draw | 70 W | 60 W |
| Transfer time | 20 ms | 4 ms |
| Parallel units | Up to 10 units | Up to 9 units |
| Solar | ||
| Max PV power | 15,000 W | 12,000 W |
| Max PV voltage (Voc) | 600 V | 500 V |
| MPPT range | 210 to 500 V | 150 to 500 V |
| MPPT trackers | 2 | 2 |
| PV current per tracker | 25 A | 20 A |
| Runs without battery | Yes | - |
| Battery and grid | ||
| Battery voltage | 48 V | 48 V |
| Battery types | Lithium, lead-acid | Lithium |
| Max charge current | 210 A | 185 A |
| Battery communication | Yes | Yes |
| Grid sell-back | Yes | Yes |
| Generator input | Yes | - |
| UL 1741 | UL 1741 SB | UL 1741 SB |
| Build | ||
| App monitoring | Included | Included |
| Enclosure | IP65 (NEMA 4X) | IP65 / NEMA 3R |
| Dimensions | 29.5 x 20.5 x 11.23 in | 29.5 x 17.7 x 10 in |
| Weight | 110 lb | 78 lb |
| Warranty | 10 years | 10 years |
| Released | 2023-06 | 2021-02 |