Transactions of the ASAE
Solar earth-water distillation is a means of extracting moisture from an earth medium. Three designs of the hot-box type of solar earth-water still were tested using wet or saturated sand. The designs included: low height with reflective interior siding, tall height with reflective siding and tall height with absorptive siding. The daily volume of distillate from different designs was compared. A twenty-centimeter-tall still with reflective siding produced significantly greater yields than one twice as tall. No significant difference in the yield between tall stills with light-absorptive versus light reflective interior siding was found. A regression equation was developed to predict water production for a low still with reflective siding and a sixteen-degree cover slope. Independent variables included soil moisture, solar radiation and maximum and minimum daily temperature.
Peralta, R.C., Skergan, T.M. and D.B. Marx. 1984. Solar earth‑water distillation for wet sand. Transactions of the ASAE. 27(6):1690‑1695.