Flexible panels weigh a fraction of rigid ones and bond straight to a curved roof. Rigid panels make more power per square foot and run cooler, and Renogy's standard N-Type rigid panels carry longer warranties. Which is right depends on your roof, how much weight you can carry up there, and how long you want the panels to last. Here is how Renogy's flexible and rigid panels compare, using Renogy's own figures.
The short answer
- Choose rigid if your roof is flat enough for brackets, you have room for the larger frame, and you want the most watts and the longest warranty.
- Choose flexible if the roof is curved (an Airstream, a teardrop, a van with ribs), if weight on the roof matters, or if you want a low, stealthy profile.
- Choose a ShadowFlux panel, rigid or flexible, if part of the roof is shaded by an AC shroud, a vent or trees for some of the day.
Renogy flexible vs rigid, by the numbers
| Panel | Type | Size (in) | Weight | Watts per sq ft | Open-circuit voltage |
|---|---|---|---|---|---|
| N-Type 100W | Rigid | 34.1 x 22.8 x 1.2 | 13.0 lb | 18.5 | 22.79V |
| N-Type 175W | Rigid | 43.7 x 30.1 x 1.2 | 21.2 lb | 19.2 | 24.48V |
| N-Type 200W | Rigid | 49.7 x 30.1 x 1.2 | 23.4 lb | 19.3 | 37.44V |
| ShadowFlux 200W | Rigid | 49.69 x 30.08 x 1.18 | 23.83 lb | 19.3 | 36.5V |
| 100W Lightweight Flexible | Flexible | 48.0 x 21.6 x 0.08 | 4.2 lb | 13.9 | 22.5V |
| Flex ShadowFlux 100W | Flexible | 37.09 x 24.13 x 0.10 | 4.19 lb | 16.1 | 33.6V |
| Flex ShadowFlux 200W | Flexible | 62.20 x 27.40 x 0.10 | 7.72 lb | 16.9 | 44.1V |
| 50W Flexible | Flexible | 26.9 x 20.0 x 0.16 | 2.87 lb | 13.4 | 24.3V |
Sizes, weights and voltages are from Renogy's datasheets and product pages. Watts per square foot is our arithmetic: rated watts divided by the panel's length times width.
Weight: flexible wins clearly
A 100W rigid N-Type panel weighs 13.0 lb. The 100W flexible weighs 4.2 lb, 8.8 lb less per panel. Across a 400W array that adds up to about 35 lb less on the roof, before you count the brackets and bolts rigid panels need. On a small trailer, a pop-top or a van close to its payload limit, that difference matters.
Power per square foot: rigid wins
Renogy's rigid N-Type and ShadowFlux panels make about 18.5 to 19.3W per square foot. The flexible panels make about 13.4 to 16.9W. On a crowded roof, that gap decides how many watts you can fit. Of the flexible panels, the Flex ShadowFlux has the highest power density, because it uses N-Type TOPCon cells.
Heat and lifespan: rigid wins
Panels lose output as they heat up, and a flexible panel glued flat to the roof has no air underneath to cool it. Renogy's own installation manual is direct about this: it does not recommend flexible panels on standard home roofs, because their heat dissipation, performance and longevity are inferior to rigid panels. For rigid panels on an RV, it asks for at least a 3.94 in (10 cm) ventilation gap between the brackets and the roof.
The warranties reflect it. Renogy's rigid N-Type panels carry a 10-year material and workmanship warranty and a 25-year, 80% output warranty. The 100W Lightweight Flexible carries a 5-year material and workmanship warranty. Its output warranty is 95% at 5 years, 90% at 10 years and 80% at 25 years.
Mounting: very different jobs
Rigid panels
Renogy's manual has you bolt rigid panels through their pre-drilled holes (M6 or M8). Use spring washers or threadlocker so vibration doesn't loosen them, and keep the ventilation gap. Most of our rigid-panel Renogy kits list Z-brackets or mounts in the box; check the kit's listing. For parked-up seasons, Renogy's tilt mount brackets let you angle the panels toward the sun. See whether tilt mounts are worth it.
Flexible panels
For moving vehicles, Renogy says to bond flexible panels with structural silicone adhesive and to use the grommets only on non-mobile installs. Its manual gives the method:
- Clean the roof and the panel back with isopropyl alcohol.
- Run neutral-cure structural silicone in beads along the long edges.
- Leave the short edges open for drainage and heat.
- Let it cure for 72 hours out of sun and rain, and don't drive during that time.
- Keep the installed bend to 30 degrees or less.
On a corrugated roof you need at least six adhesive contact lines. If you can't get them, Renogy says flexible panels are not suitable. And don't walk on either type.
Check the voltage against your controller
This catches people who add a panel to an older kit. Renogy's 200W N-Type and ShadowFlux panels are higher-voltage panels, about 37V open-circuit, and the Flex ShadowFlux runs 33.6V (100W) or 44.1V (200W). They need an MPPT controller such as a Rover Li. Renogy's Wanderer Li 30A PWM controller accepts a maximum PV input of 25V. That suits 12V-class panels like the 100W rigid (22.79V) or the 100W flexible (22.5V), but not a 200W N-Type. Renogy pairs the Wanderer with a 100W N-Type panel in its 100W kit, but there is little margin: using the same -0.26%/°C coefficient, at 14°F (-10°C) the 100W rigid's 22.79V rises to about 24.9V, so in deep cold it sits right at the limit.
Cold weather raises a panel's voltage. Using Renogy's temperature coefficient of -0.26%/°C for the 175W, its 24.48V rating rises to about 26.7V at 14°F (-10°C). That is over the Wanderer's 25V limit, so pair the 175W with an MPPT too.
Shade: where ShadowFlux earns its place
Renogy says its ShadowFlux anti-shading design keeps up to 85% of output under partial shade. The rigid ShadowFlux 200W and the Flex ShadowFlux both use it. If an AC unit or a vent fan shades the roof for part of the day, it is worth the step up. On an open, unshaded roof, the standard N-Type does the same job. Our answer ShadowFlux or standard N-Type goes into it.
Which should you buy?
- Flat roof, space for brackets, long ownership: N-Type rigid, or the ShadowFlux 200W for shaded roofs.
- No roof install at all: see Renogy portable solar panels.
- Curved roof, weight limits or a low profile: Flex ShadowFlux for the most watts per square foot in a flexible panel, or the 100W Lightweight Flexible.
- Want a complete kit? The 400W Starter Kit comes with either two rigid 200W N-Type panels or two 200W flexible panels and a Rover 40A MPPT. Check what else a Renogy kit needs.
Not sure how many watts you need? Start with What size solar kit do I need? or our RV solar and battery calculator, then browse solar power. Found it cheaper? We'll beat it.
FAQ
Can I mix flexible and rigid panels?
It can be done, but Renogy's installation manual strongly recommends panels of the same specification and batch, because mixing power ratings or ages cuts output. If you do mix, match voltages on anything wired together, and keep higher-voltage and 12V-class panels on separate controllers.
Can I screw a flexible panel to my roof?
Not with grommets alone on a moving vehicle, per Renogy. Bond it with structural silicone. For corrugated roofs, Renogy's manual allows optional M5/M6 bolts as extra fastening once the silicone has cured.
Are flexible panels less efficient?
Per square foot, yes, by Renogy's own sizes and ratings: about 13 to 17W per square foot against about 19W for the rigid N-Type. They also run hotter when glued flat.
Are both types built for wind and snow?
Renogy rates both the rigid N-Type and the 100W Lightweight Flexible for 2,400 Pa wind and 5,400 Pa snow loads.