LIFE CYCLE COST ANALYSIS OF A MULTI-TRAY SOLAR DRYER WITH THERMAL ENERGY STORAGE BED

¹Benjamin Ternenge Abur and ²Muhammad Hadi Ibrahim

^1,2Department of Mechanical/Production Engineering, Faculty of Engineering and Engineering Technology, Abubakar Tafawa Balewa University, Bauchi

¹engrbenjaminabur@gmail.com

ABSTRACT

A simple multi-tray natural convection solar dryer incorporating a sensible thermal energy storage bed has been developed using locally sourced materials. The sensible heat material is gravels of 45kg beneath the solar air heater.  Test evaluation shows a temperature range of 29 to 56.5°C for the drying chamber while the heat storage bed temperature ranges between 31 to 57.8⁰C at the uppermost part of the bed. It took 48 hours to reduce the moisture content of 7.50kg of fresh tomatoes at 93% to 5.5% under the weather condition of Bauchi in the month of February. Samples dried with the solar dryer were of superior quality compared to the open sun method. The computed payback period of the solar system ranges from 2.42 to 4.28 years using the annualized cost method and is lower than the expected life of the dryer. Also the amount of money that could be save from using the system compare to an electric powered dryer is worked out including the present worth, annual cash flow and cost of drying.

Keywords: Indirect solar dryer, thermal energy storage material, life cycle cost, payback period.