The Sad Truth about Flexible Solar Panels

I've seen a fair number of people interested in fully flexible (rollable) panels because of their "easy storage." There's a big gotcha here that the manufacturers have done a good job concealing. Let's look at some real panels to see what the problem is:

Consider the Uni-Solar FLX-32, a common fully-flexibly panel. The rated wattage is 32W, and the size is 55.77x16.7" or 0.60m^2. These numbers give an efficiency of only 5.3%. Yikes! Genasun's 110W panel measures 47x21" or 0.64m^2, for an efficiency of 17.3%. Even conventional panels are typically 10-14% efficient. So, is a rollable panel really easier to store if it's 2 or 3 times the size of an equivalent flat panel? Maybe, but the flat panel can be slipped next to a bulkhead, beside a box, or under a cushion, while the rolled panel now takes up a lot of volume, and must be protected from crushing.

If compact storage is foremost, consider the foldable panels that some companies have begun to offer. These panels contain rigid sections bound to a nylon or other flexible backing so they can fold up accordian-style. These panels appear to combine the efficiency of rigid panels with the supposed ease of storage of flexible panels, and would seem to be a good solution if your panel must be stored in a space of small linear dimensions.

-Alex, 11/2006