Experimental investigation of the evacuated tube under Iraq weather conditions utilizing first and second law efficiency

This article presents the results of a field test of an evacuated-tube solar water heater and provides an analysis of those results. The first and second principles of thermodynamics were used to analyse the performance of the evacuated tube solar water heater. Between 6:00 PM and 6:00 AM before each test, the whole tank's water supply was renewed. After 24 hours of operation in the month of November, the water temperature in the tank reached 33.5 degrees Celsius. The ETSWH achieved an efficiency of 76.1% according to the first law, while the second law efficiency was 5.2%. Morning tank water temperatures averaged 33.5 degrees Celsius. The ETSWH's daily energy efficiency was 57.2%, and its exergy use efficiency was 4.48 %