Water is essential for life on Earth. Desalination may help alleviate the water shortage problem by transforming saltwater into drinkable water. This study examines a solar-desalination system that incorporates a humidifier and dehumidifier. This work uses a trapezoidal cross-flow heat exchanger as a dehumidifier to provide a novel method of quantifying solar humidification dehumidification (HDH) desalination. The proposed technique for dehumidification involves utilizing a trapezoidal unmixed cross-flow to enhance the condensation rate of distilled water. The number of internal trapezoidal paths, hot air flow rate, feed water flow rate, and the dehumidifier cooling technique were studied experimentally. According to the results, more internal trapezoidal paths improve productivity due to increased condensation surface area during natural cooling. Furthermore, the use of forced external cooling to increase the condensation rate is also investigated. However, the suggested system can produce about 32.6 kg of distilled water daily, and one liter of distilled water costs 0.0041$.