Portable panels can be highly-productive and useful, but good results require owner discipline.

Rated watts are rated watts; a 100w portable will make the same power as 100w mounted in a lab.

When framed panels are used as portables they are no different than any other panel. Suitcase and some standalone panels are often made of “flex” crystalline cells that break over time.¹⁾ CIGS or other film-based cells can flex.

Portables can outperform flat-mounted panels when they are

• set out facing ~south²⁾ at seasonally-optimal tilt in clear weather³⁾; or
• moved throughout the day to optimally face the sun in clear weather. This can increase harvest over fixed tilt but requires frequent repositioning. To give you an idea, automated single-axis trackers that follow the sun automatically can increase yield over fixed tilt by 20-35%. Increases from occasional owner repositioning will be lower.
• set out in the sun when the mounted solar needs to be shaded. For example, in hot weather the van can be emplaced against the eastern edge of a treeline. This will allow mounted panels to collect sun until ~noon and be shaded thereafter. Portables placed further east and facing west⁴⁾ will run loads after the trees shade the van. Example setup.

• owners not setting them out for whatever reason ←- the biggest issue
  • laziness
  • “won't be here that long”
  • panel isn't waterproof and it might rain (or has rained)
  • stealth camping in the city and no place to deploy them safely
  • high winds
• set out but fell/blew over face-down
• set out in overhead shade or high grass shade
• set out facing north (!!) {“as I write this there are two rigs in my line of sight with this unforced error.” - secessus} Note: setting out facing east or west can make sense if direct sun is only available in that direction, or if one is manually “tracking” the sun.
• made of “flex” crystalline that breaks
• loose dogs pissing on them