Sol-Ark 18K-2P
For large homes that want seamless whole-house backup with no load shedding. Few inverters match its output, but it costs well over most rivals.
Shop Solar Kits $6,298$6,298
The Sol-Ark 18K-2P and the SunGoldPower Freedom Pro 16K-48 are evenly matched, rated 4.1 and 4.1. The Sol-Ark 18K-2P leads on solar input and features. The SunGoldPower Freedom Pro 16K-48 wins on value. The SunGoldPower Freedom Pro 16K-48 costs $3,599 less ($2,699 vs $6,298).
SunGoldPower Freedom Pro 16K-48
A very large off-grid split-phase inverter for big homes, farms and shops that want one unit instead of a stack.
SunGoldPower $2,699$2,699
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 Sol-Ark 18K-2P for solar input (28,800 W of panels, 500 V max, 3 MPPTs vs 24,000 W of panels, 600 V max, 2 MPPTs) and features (UL 1741 listed, Wi-Fi app, parallel stacking, grid sell-back, generator input, battery communication vs UL 1741 listed, Wi-Fi app, parallel stacking, generator input, battery communication; no grid sell-back).
- Choose the SunGoldPower Freedom Pro 16K-48 for value ($169 per kW of continuous output vs $350 per kW of continuous output).
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 | Sol-Ark 18K-2P | SunGoldPower Freedom Pro 16K-48 |
|---|---|---|
| Overall rating | 4.1/5 | 4.1/5 |
| Value 30% | 70 $350 per kW of continuous output | 100 $169 per kW of continuous output |
| Solar input 20% | 80 28,800 W of panels, 500 V max, 3 MPPTs | 68 24,000 W of panels, 600 V max, 2 MPPTs |
| Efficiency 20% | 43 110 W idle | 54 94.3% peak efficiency |
| Features 15% | 100 UL 1741 listed, Wi-Fi app, parallel stacking, grid sell-back, generator input, battery communication | 85 UL 1741 listed, Wi-Fi app, parallel stacking, generator input, battery communication; no grid sell-back |
| Warranty 15% | 100 10-year warranty | 50 warranty not published (neutral score used) |
Specifications
| Sol-Ark 18K-2P | SunGoldPower Freedom Pro 16K-48 | |
|---|---|---|
| Output | ||
| Output voltage | 120/240 V split-phase | 120/240 V split-phase |
| Continuous output | 18,000 W | 16,000 W |
| Surge | 36,000 W | 32,000 W |
| Peak efficiency | - | 94.3% |
| Max efficiency | 97.6% | - |
| CEC efficiency | 97% | - |
| Idle draw | 110 W | - |
| Transfer time | 5 ms | 10 ms |
| Parallel units | Up to 12 units | Up to 6 units |
| Solar | ||
| Max PV power | 28,800 W | 24,000 W |
| Max PV voltage (Voc) | 500 V | 600 V |
| MPPT range | 150 to 425 V | 120 to 550 V |
| MPPT trackers | 3 | 2 |
| PV current per tracker | 36 A | 36 A |
| Runs without battery | - | Yes |
| Battery and grid | ||
| Battery voltage | 48 V | 48 V |
| Battery types | Lithium, lead-acid | Lithium, lead-acid, user-defined |
| Max charge current | 350 A | 300 A |
| AC charge current | - | 300 A |
| Battery communication | Yes | Yes |
| Grid sell-back | Yes | No |
| Generator input | Yes | Yes |
| UL 1741 | UL 1741 SB | Yes |
| Build | ||
| App monitoring | Included | Included |
| Enclosure | IP65 / NEMA 3R | IP20 |
| Dimensions | 34 x 19.4 x 12 in | 24.5 x 33.61 x 8.48 in |
| Weight | 137 lb | 105 lb |
| Warranty | 10 years | - |
| Released | 2025-09 | 2026-10 |