Period of performance:
Freshwater is an increasingly scarce resource, with many regions such as the southwestern US experiencing intense droughts. Many are turning to seawater desalination to satisfy growing freshwater demand, driving the need for desalination on a distributed scale to be as economical as large-scale desalination. This project addresses the challenges associated with scalability, cost and water safety by capitalizing on a recent invention by the PI that achieves high evaporation rates and high-efficiency by localizing solar radiation to the surface of water. A wavelength-selective, insulating-thermally, solar-powered still (WISPS) tarp structure is being developed that can blanket surfaces of oceans and lakes to generate freshwater onsite. This structure integrates several characteristics: spectral selectivity (high solar absorptance and low thermal emittance), thermal insulation, thermal concentration, salt-repelling, anti-fouling, and low-cost manufacturability. The structure is easy to install, and is made with commercially available materials. Combining WISPS with a simple water condensation system, we anticipate clean water production from seawater at low capital costs and competitive production costs compared with large scale systems.