Multi effect solar still (MES) has a stack of multiple layers for evaporation and condensation. The latent heat dissipated during condensation at the front layers are repeatedly recycled for evaporation at the back layers to increase overall desalination productivity. Despite of high efficiency and long history, MES has not been widely used yet, because of relative high cost. In this chapter, newly designed MES is introduced. Since it has low cost, light weight material and simple structure, it could be easily mass even at less developed country. The cost of production for a 1 m2 unit is expected to be less than 300 USD. Structural features are introduced with experimental result which was outdoor tested with homemade lab prototype with 0.219 m2 effective area. 9kg/m2 per day of fresh water was obtained at sunny day (19.5MJ/m2) in Seoul, Korea, which is close to WHO’s recommended minimal daily water supply for individuals (7.5~15 liters). For more practical implementation, further development on prototype and production process should be made as well as long term outdoor test under actual climate it would be used. Worldwide collaboration would be necessary for speeding up implementation.
Part of the book: Desalination