Researchers at the Indian Institute of Science have developed a solar hybrid desalination system that works for saline and brackish water.
The researchers have published data showing the system can purify nearly 6.5 litres of saline water per square metre of the instrument panel in the South Indian sun between 9 am and 3 pm at around 27 ºC.
The stepped solar-still, comprised semi-circular pipe sections welded one next to the other to create a constant incline to serve as the water channel basin. Vacuum jackets minimize thermal losses.
The instrument could hold 3-4 litres for treatment. During the experiments, solar intensity was observed at 718.76 w/m². Evaporation was achieved at below 100 ºC. Water was pumped in and out using photovoltaic cells as a source of energy — making the device self-reliant.
The process has been published in the International Journal of Low Carbon Technologies.