This study introduces a novel concave solar still (CNSS) that integrates a vertical zig-zag wick (VCWSS) and silver-enhanced phase change material (PCM-Ag) to overcome the low productivity of conventional solar stills (CSS). The design's novelty lies in its concave basin, which increases the vaporization area by 70% using transparent sidewalls to maximize irradiance capture, coupled with a thermal cascade from the VCWSS for waste heat recovery. Experimental testing under the climatic conditions of Baghdad, Iraq, demonstrated that the CNSS alone produced 7800 mL/m2 center dot day, a 160% enhancement over the CSS (3000 mL/m2 center dot day). Integration of the VCWSS boosted the combined yield to 12,300 mL/m2 center dot day (290% improvement), while the full system with PCMAg achieved an optimal output of 13,650 mL/m2 center dot day, representing a 326% enhancement. Thermal efficiency progressed from 58% for the basic CNSS to 76.4% for the fully integrated system. These performance gains are achieved without increasing the horizontal land footprint relative to a conventional solar still, making the proposed configuration suitable for decentralized installation in land-constrained or rooftop settings in arid regions. However, the practical deployment of the CNSS-VCWSS-PCM-Ag system requires consideration of the additional capital cost of PCM-Ag integration, long-term stability of wick materials, and the dependence on high solar irradiance, which may limit performance in low-insolation climates.