Sol-Ark 15K-2P
For homeowners and installers who want a long-proven whole-home hybrid with strong support. It costs more than EG4 for similar output.
Amazon Shop Solar Kits $4,999$4,999
4.0/5
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.
- 6.5 kWOutput
- 48 VBattery
- 10,000 WSolar input
- 80 WIdle draw
- 5 yearsWarranty
Check price at Current Connected$1,549Check price at Wind & Sun$1,549
Price checked October 23, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Makes 120/240 V from one unit and takes 10,000 W of panels
- Separate generator port with auto-start
- UL 1741 listed for permitted off-grid installs
- Up to six units in parallel as needs grow
Cons
- About 80 W idle draw uses close to 2 kWh a day
- Cannot export to the grid
- Indoor IP20 enclosure needs a dry, sheltered spot
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-SOLO-6.5K |
|---|---|
| Output | |
| Output voltage | 120/240 V split-phase |
| Continuous output | 6,500 W |
| Surge | 13,000 W |
| Peak efficiency | 93% |
| Idle draw | 80 W |
| Transfer time | 10 ms |
| Parallel units | Up to 6 units |
| Solar | |
| Max PV power | 10,000 W |
| Max PV voltage (Voc) | 550 V |
| MPPT range | 150 to 450 V |
| MPPT trackers | 2 |
| PV current per tracker | 18 A |
| Runs without battery | Yes |
| Battery and grid | |
| Battery voltage | 48 V |
| Battery types | Lithium, lead-acid |
| Max charge current | 140 A |
| AC charge current | 80 A |
| Battery communication | Yes |
| Grid sell-back | No |
| Generator input | Yes |
| UL 1741 | Yes |
| Build | |
| App monitoring | Included |
| Enclosure | IP20 |
| Dimensions | 27 x 16.1 x 6.1 in |
| Weight | 50.7 lb |
| Warranty | 5 years |
| Released | 2026-01 |
Alternatives in this output
SunGoldPower SGS-12K18MAX
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$2,990
Fortress Power Envy 8K
For grid-tied homes with moderate backup needs that want an outdoor hybrid with export and US-based support.
Wind & Sun $3,735$3,735
Compare
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