Design and performance analysis of a thermoelectric air-conditioning system driven by solar photovoltaic panels

Abstract

Solar cooling technologies can play a vital role in renewable energy applications development. Thermoelectric systems have shown promising advantages over traditional refrigeration systems such as high thermal comfort, active adaptability, no moving parts, and refrigerants free. In this work, a novel thermoelectric air-conditioning system (TEACS) driven by photovoltaics (PV) is experimentally and theoretically investigated under the hot climate conditions of Sohag city (30°26′N, 42°31′E), Egypt for air conditioning of a typical small-size office room under different thermal loads. During day time, PV panels produce electricity which utilized to drive the TEACS directly and to charge batteries that store electricity to be exploited during nighttime. Moreover, a numerical model implemented in TRNSYS coupled with MATLAB software is developed to evaluate the performance of the proposed TEACS. The influences of varying the input electric current on the coefficient of performance (COP), cooling capacity, and average air room temperature are also studied. The results showed that a design point with an input current of 2.5 A for a cooling capacity of 30 W could be selected to maximize the cooling performance, in which the COP of the TEACS is found to be 2.2. Moreover, the daily average air temperature of the conditioned room was found to be 23.5, 25.5, 27.5, 28.5, and 30.5  °C for internal thermal loads of 0.0 W, 65.0 W,130.0 W, 195.0 W, and 260.0 W, respectively, at average air intake temperature of 36  °C, daily average input current of 4.28 A and air volume flow rate of 14.4 m3/h. It can be concluded that the TEACS powered by PV could be considered as a proper alternative to the traditional vapor compression systems.