Energy and exergy analysis of different Trombe walls

• The thermal performance of two types of Trombe walls was compared.
• The energy efficiency was not high and the exergy efficiency was very low.
• The influence factors of energy and exergy efficiencies were obtained.
• The exergy destruction due to absorption of the absorber plate was the largest.
• Two effective methods to increase energy and exergy efficiencies were obtained.

This study aims to compare the thermal performance of two different types of Trombe wall: one with the absorber plate pasted on the thermal storage wall (Type I) and one with the absorber plate placed between the glass cover and the thermal storage wall(Type II). The glass cover is double glazed. The energy and exergy efficiencies of the Trombe walls are evaluated for various air channel depths, solar radiation intensities and the emissvities of the glass cover. The energy and exergy efficiencies, the airflow rate and air temperature rise in the air channel in the Trombe wall with the absorber plate placed between the glass cover and the thermal storage wall(Type II) are higher than those in the Trombe wall with the absorber plate pasted on the thermal storage wall(Type I). In addition, it is found that the particular exergy destruction due to absorption of the absorber plate is the largest and that a higher absorber plate temperature is preferable in decreasing the total exergy destruction and increasing exergy efficiency.