Over the past fifteen years I’ve watched the commercial availability of raw solar cells evolve, with a sharp interest in using these cells to create custom forms, curved surfaces, and aesthetically integrated pv systems for interactive sculptures. The first version of the leaf for Heliotropis was a ridiculous assemblage of many hand-cut polycrystalline cells which were laminated beneath a kiln-formed glass panel. While early tests showed good power production in full sun, I soon realized that structural integration of the panel into the sculpture would require pressure to be placed on the cells and could cause cracking.
A more reliable solution was found in thin-film cells from Powerfilm, though the cells I used were not waterproof and required lamination similar to the polycrystalline cells. Eventually, ironically, rising waters during hurricane Sandy partially submerged the panels and water penetrated the lamination, which ruined the Powerfilm cells.
In the end, the solution became a separate pv installation which powers Heliotropis. I was against this solution for years after I first had issues making the leaves, but given the lack of reliability of previous methods the implementation of a commercially made panel was ideal for me.
What I have learned is that custom fabrication of modules that can offer archival durability outdoors is extremely challenging. Furthermore, creating curved surfaces made up of many discrete solar cells is very inefficient without complex power management strategies. After many trials, I am happy to have found a commercially available 5w panel that I can integrate into larger organic forms to achieve the desired aesthetic.