Efficiency reduction of photovoltaic cells caused by increasing temperature, is an important issue that restricts their use in the middle of the day especially in summer. A new cost-effective method to increase the solar cell efficiency is presented to alleviate the problem. A combination of 40 fiberglass small cells are used in the form of a panel to perform the experimental tests. Water is used as absorbent of heat to reduce high temperature effects on the panel and the test results show that the panel efficiency is increased using the suggested method by amount of at least 16.8%. A 300W halogen lamp is regarded as the light source throughout the experiments.