Theoretical and experimental analyses of solar-thermoelectric liquid-chiller system

• Analytical model for solar-thermoelectric liquid chiller (STLC) system is developed.
• STLC system can remove more heat with increasing bulk mean temperature of the water.
• Effect of flow rate on the heat removal rate is small.
• Electrical current is optimized to achieve maximum heat removal rate.
• Prototype STLC system can simultaneously cool water and conditioned space.

A solar-thermoelectric liquid chiller (STLC) system is constructed and characterized using both theoretical and experimental analyses. A cold-plate (plate and tube type) heat exchanger, attached to the cold side of the STLC system, is utilized for removing the heat from the circulating water in the system. Analytical models include the thermoelectric Peltier effect, thermal convections in air and water, and conductions within the solid parts of the STLC system. Proposed analytical models are used to calculate different performance parameters (e.g., heat removal rate and coefficient of performance) of STLC system at different input electrical currents, temperature differences (between the bulk mean temperature of the liquid and the surrounding environmental temperature), and flow rates. Optimum values of the electrical current are calculated to achieve maximum heat removal rates for a wide range of temperature differences. It is observed that the heat removal rate by the STLC system increases with increasing bulk mean temperature of the water for considered ambient temperature conditions. However, small changes in the heat removal rate are observed when liquid flow rate changes inside the cold-plate heat exchanger. A prototype of the conditioned space is constructed to perform the experimental analysis. Experimental analysis includes the monitoring of the cooling down period of the water and conditioned space to achieve desired temperatures.