Solar Power--Where to buy solar cells?

[Bbrooke]

I have looked all over for an online store where I can buy Amorphous, Single Crystal Silicon, and Polycrystalline solar cells. I can find each of these...but they're on seperate sites, and have different surface areas/ average voltage outputs. Preferably, I would like to find a site that had all three of these solar cells; since that seems impossible, though, what I need now is to find at least these three solar cells with the same voltage output. (for example, all of them could be .5 volts, or 3 volts...) The price range I'm looking at is under $30 for each cell. Any science store reccommendations? I've already exausted Edmunds and Wards Science. Thank you!

[bradleyshanrock-solberg]

I'm not sure you can get all of them identical but you can probably work out the formula to account for the different geometries.

Have you had algebra? It's a basic practical algebra problem.

The formula is:

length*width*(constant based on material) = voltage

If you know length, width and voltage you can determine how the three materials stack up compared to each other.