A grid-interactive 12 kW whole-home hybrid with UL 1741 SB listing, for homeowners who want to sell solar and back up the house.
SunGoldPower $2,990
For grid-tied homes with moderate backup needs that want an outdoor hybrid with export and US-based support.
- 8 kWOutput
- 48 VBattery
- 13,000 WSolar input
- 70 WIdle draw
- 10 yearsWarranty
Price checked October 23, 2026. As an Amazon Associate we earn from qualifying purchases.
- 8 kW of 120/240 V with export to the grid under UL 1741 SB
- Takes 13,000 W of panels on two trackers
- Outdoor-rated case and a ten-year warranty
- About 70 W idle draw costs close to 2 kWh a day off grid
- Weighs 110 lb, a two-person mount
- Costs more per kW than the EG4 and Growatt alternatives
The Fortress Envy family
Every Fortress Envy model we rank, smallest first. Ratings compare each against its own output.
| Model | Output | Rating | Price |
|---|---|---|---|
| Fortress Power Envy 8K (this one) | 8 kW | 4.0/5 | $3,735 |
| Fortress Power Envy 10K | 10 kW | 4.1/5 | $3,899 |
How it scores
The rating comes from 5 measured or published factors, each scored 0-100 against fixed reference points for its output. How we rank explains each one.
Specifications
| Model number | FP-ENVY-8K |
|---|---|
| Output | |
| Output voltage | 120/240 V split-phase |
| Continuous output | 8,000 W |
| Surge | 16,000 W |
| Peak efficiency | 94% |
| CEC efficiency | 96.5% |
| Idle draw | 70 W |
| Transfer time | 20 ms |
| Parallel units | Up to 10 units |
| Solar | |
| Max PV power | 13,000 W |
| Max PV voltage (Voc) | 600 V |
| MPPT range | 170 to 500 V |
| MPPT trackers | 2 |
| PV current per tracker | 25 A |
| Runs without battery | Yes |
| Battery and grid | |
| Battery voltage | 48 V |
| Battery types | Lithium, lead-acid |
| Max charge current | 167 A |
| Battery communication | Yes |
| Grid sell-back | Yes |
| Generator input | Yes |
| UL 1741 | UL 1741 SB |
| Build | |
| App monitoring | Included |
| Enclosure | IP65 (NEMA 4X) |
| Dimensions | 29.5 x 20.5 x 11.23 in |
| Weight | 110 lb |
| Warranty | 10 years |
| Released | 2023-06 |
Alternatives in this output
For off-grid cabins, ADUs and backup systems that want 240 V and a large solar input from a US-supported brand. It costs a little more than the EG4 6000XP.
Current Connected $1,549 Wind & Sun $1,549For homes that want Sol-Ark’s backup and grid-sell features on a smaller budget, usually on a critical-loads panel. Its high idle draw is the main trade-off.
Shop Solar Kits $3,849Compare
Compare the Fortress Power Envy 8K with any other hybrid solar inverter →
More from Fortress Power: every Fortress Power product ranked.