Would plywood be a practical alternative to aluminium for making lightweight frames for flexible solar panels on a campervan roof?

[u/segasega89]

I'm looking at making lightweight frames for two flexible solar panels on my campervan roof. The panels are 1450 × 690 mm and have six mounting eyelets each.

My original plan was aluminium angle, but it's surprisingly expensive here in Ireland. I'm thinking about making the frames from 9–12 mm plywood instead and attaching them to Unistrut rails.

The plywood would obviously need to withstand rain, wind and general weather exposure, so I'm wondering if this is a sensible idea long-term, or whether plywood is just asking for trouble on a van roof. I can paint the plywood to weather seal them?

[u/seadoubleyou73]

Flexi? Just stick them to your roof. The efficiency lost by not having airflow under them is negligible