An experimental system was developed and tested in order to investigate the exergetic performance of a solar photovoltaic system (PV) assisted earth-to-air heat exchanger (under ground air tunnel) that is used for greenhouse cooling at the Solar Energy Institute, Ege University, Izmir, Turkey. This system was under operational conditions successfully during the 2010 summer cooling season. This paper provides the experimental results obtained between 18th of August and 26th of August of in 2010. Exergy destruction in the system was calculated and presented in this paper using a reference temperature of 15 degrees C. Results are discussed and interpreted in the paper for various performance metrics, such as the effect of climatic conditions and operating conditions on the system performance. Results show that the system may be satisfactorily used for greenhouse cooling in the Mediterranean and Aegean regions of Turkey. (C) 2011 Elsevier B.V. All rights reserved.