Building solar panels can be a fun and interesting project, however, it's important to understand what you are dealing with. The homemade built panels should mostly be used for smaller applications such as providing light for a shed, powering small electronics etc. If you are wanting to build high wattage/current solar panels in attempt to provide electricity into your home or a bigger project, this is not recommended. Here is why:
First, homemade solar panels are said to not last as long and you will see the efficiency decrease in a shorter period of time. Manufactured solar panels usually come with a 25 year warranty and last considerably longer than homemade panels (25+ years).
Homemade solar panels do not have the proper certifications to qualify for the state and federal tax rebates. Without these certifications, you wouldn't be compliant with the building/electrical code or insurance companies. It would take thousands of dollars and several months to get your panels listed by a NRTL(Nationally Recognized Testing Laboratories).
It could be a fire hazard. You should never put high powered, homemade panels consisting of wood and/or plastic over your home or flammable material. You would want to mount them on bare ground, a concrete surface, etc.
An alternative for off grid or other solar projects is getting blemished solar panels. (www.sunelec.com) These type of panels have small blemishes that don't really affect the output of the panels. You can get these type of panels for $2.50/w up to $4/w including a 25 year warranty. These types of panels are not UL listed. The prices of commercial, UL listed solar panels are currently going for $4-5 per watt.
Lastly, don't pay for those DIY Solar Panel Guides you see polluting the Internet, such as Earth4Energy.
See Here: Earth4Energy Scam
These guides are nothing more then a bunch of information gathered from the Internet that you can get for free anyway. Your better off just coming here to Solar Panel Talk and learn for free.
This thread is intended to shed some reality on what your getting into, not to tell you it's not possible!
Any other input is welcome and encouraged. Thanks for reading!