Project Name: Low-Cost Desalination Using Nanophotonics-Enhanced Direct Solar Membrane Distillation
Funding Opportunity: Solar Desalination
SETO Subprogram: Concentrating Solar Power
Location: Houston, TX
SETO Award Amount: $1,699,988
Awardee Cost Share:  $676,075
Principal Investigator: Qilin Li

The project team will build a Nanophotonics-Enhanced Direct Solar Membrane Distillation (NESMD) system. NESMD is a novel, integrated, one-step solar collection and desalination process that has the potential to lower the cost of treating high-salinity water. It will use a membrane that converts sunlight to heat and purifies water at the same time. The team will develop, test, and optimize a pilot NESMD system for low-cost solar desalination.


The team will design, test, and optimize a pilot-scale NESMD system. NESMD combines solar-thermal collection and membrane distillation in a single reactor by using a photothermal membrane, which captures sunlight and converts it to heat without externally heating the water, helping to lower operation costs. The project team will test the system under real-world working conditions and develop mathematical models at different scales to characterize the optical, thermal, and mass transfer processes that occur during solar collection and desalination.  


Most desalination technologies require one process for solar-thermal collection and one for membrane distillation, but the NESMD technology combines them into one process. Through localized heating, NESMD maximizes the solar-thermal efficiency and the overall energy efficiency of the membrane distillation process while minimizing heat loss and saving costs. These innovations will improve energy efficiency and lower equipment costs, making solar desalination more affordable.