In this paper, a thorough review of photovoltaic and photovoltaic thermal systems is done on the basis of its performance based on electrical as well as thermal output. Photovoltaic systems are classified according to their use, i.e., electricity production and thermal applications along with the electricity production. The application of various photovoltaic systems is also discussed in detail. The performance analysis including all aspects, e.g., electrical, thermal, energy, and exergy efficiency are also discussed. A case study for PV and PV/T system based on exergetic analysis is presented. (C) 2009 Elsevier Ltd. All rights reserved.