The current studies on the thermohydraulic performance enhancement of solar air heaters are carefully reviewed regarding increasing surface area by double-pass solar air heaters (SAH), which contain artificial absorbing surfaces, thermal storage, and multi passage. Due to the low thermal efficiency of SAHs, researchers were compelled to concentrate on enhancing the thermal performance of SAHs by proposing artificial flow modification approaches in the flow field. A double-pass solar air heater (DPSAH) is thought to be more efficient than a single-pass solar air heater (SPSAH) when comparing thermal performance. The present work provides a comprehensive overview of the existing and current sustainable approaches DPSAH with thermal storage, absorber plates containing fins, various artificial roughness, packed beds, and recycling. The literature also focused on the performance improvement and mathematical model of double-pass SAH. Additionally focused on were the high rate of heat transfer and lower thermal losses due to thermal storage and effective insulating materials in the DPSAH system. This study covers the applications of DPSAH as well as their functionality, comparison, and future transformation potential.