In this research, solar energy has been stored using the paraffin with the latent heat technique for heating the plastic greenhouse of 180 m(2). Energy and exergy analyses were applied for evaluation of the system efficiency. An average values of the rates of heat and thermal exergy stored into the HSV were 1740 W and 60 W for the charging periods. It was determined that the average values of the net energy and exergy efficiencies of the system were 41.9 % and 3.3 %, respectively. (C) 1998 Elsevier Science Ltd. All rights reserved.