The Renogy Black Division 100W Flexible is the better portable solar panel overall, rated 4.3 to 4.1. The Renogy Black Division 100W Flexible leads on portability. The GRECELL 100W Portable (SP-100) wins on efficiency and features. The GRECELL 100W Portable (SP-100) costs $15.11 less ($109.98 vs $125.09).
A low-profile 100 W panel for curved or weight-limited van, RV and boat roofs, especially where an all-black look matters. On a flat roof that can take the weight, a rigid panel lasts longer for less money.
Amazon $125.09A dependable, low-voltage 100 W briefcase panel for small power stations, with adapters for most older barrel and Anderson inputs. Owners of XT60 stations should budget for an adapter.
Amazon $109.98Prices were last checked October 24, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Each factor is scored 0-100 against the same fixed reference points for every small portable solar panel; a clear win is highlighted. How we rank explains each one.
| Factor weight | Renogy Black Division 100W Flexible | GRECELL 100W Portable (SP-100) |
|---|---|---|
| Overall rating | 4.3/5 | 4.1/5 |
| Value 30% | 98 $1.25 per rated watt | 100 $1.10 per rated watt |
| Tested output 20% | 100 not yet tested; estimated 91% of rated watts from 2 tests of Renogy panels and the median of the 11 tested panels | 100 best measured 100% of rated watts (1 test) |
| Portability 15% | 100 18.9 W per lb (5.3 lb (2.4 kg)) | 35 10.2 W per lb (9.8 lb (4.5 kg)) |
| Durability 15% | 100 IP67, 5-year warranty | 50 IP rating and warranty not published (neutral score used) |
| Efficiency 10% | 0 15.7% claimed efficiency | 75 23.5% claimed efficiency |
| Features 10% | 0 no kickstand, USB or bifacial cells | 55 built-in kickstand, series/parallel |
No independent test published yet.
| Tested by | Measured peak | Of rated | Conditions |
|---|---|---|---|
| The Gadgeteer | 100 W | 100% | Reviewer saw the wattage ‘jump right to 100+ watts’ and hold there on a winter day, kickstands angled for the low sun, charging a GRECELL T-500 power station; metering method not stated. Review published December 2022. |
| Renogy Black Division 100W Flexible | GRECELL 100W Portable (SP-100) | |
|---|---|---|
| Output | ||
| Rated power | 100 W | 100 W |
| Tested output | Not tested (estimated 91%) | 100 W (100%) |
| Efficiency | 15.7% (module efficiency per Renogy's spec table; the Amazon listing quotes 22%) | 23.5% (cell efficiency per GRECELL's SP-100 spec table (grecell.com product feed)) |
| Cells | Monocrystalline (half-cut PERC) | Monocrystalline |
| Bifacial | No | No |
| Electrical | ||
| Open-circuit voltage (Voc) | 23.5 V | 23.9 V |
| Voltage at max power (Vmp) | 19.4 V | 20 V |
| Short-circuit current (Isc) | 5.5 A | 5.2 A |
| Current at max power (Imp) | 5.2 A | 5 A |
| Series / parallel | - | Yes |
| Connections | ||
| Output connector | - | MC4 |
| Cables included | - | MC4 to Anderson cable, MC4 to DC5521 cable, DC5521 to DC5525 adapter, DC5521 to DC7909 (8 mm) adapter, DC5521 to DC3515 adapter |
| USB ports | None | - |
| Build | ||
| Weight | 5.3 lb (2.4 kg) | 9.8 lb (4.5 kg) |
| Flexible | Yes, bends up to 240° | - |
| Dimensions | 43.0 x 22.9 x 0.8 in (1093.0 x 582.0 x 20.5 mm) | - |
| Folded size | - | 25.2 x 21.1 x 2.5 in (640 x 536 x 65 mm) |
| Unfolded size | - | 50.55 x 21.1 x 0.2 in (1284 x 536 x 5 mm) |
| Kickstand | No | Yes |
| Water resistance | IP67 | - |
| Warranty | 5 years | - |
| Output warranty | 5-year output warranty | - |
| Released | 2025-09 | 2022-09 |
