The most efficient solar panel technology is currently about 17%, most commercially produced panels are in the 10 - 11% range, and is uber expensive. Once you consider the additional losses of the wiring, inverter and storage batteries in the system the concept of using a solar panel to produce it's own self sustaining source of energy isn't possible.
The guru's at
FSEC have been working on thin film and other applications for years. When I was there in April I was amazed at the possibilities for solar. In the next 5 - 20 years they expect huge gains in the solar field based on emerging technologies for building integrated products like paint, membranes, roof tiles, etc.