It surprises me that we haven't worked out a more efficient solar distillation process for desalination. Reverse Osmosis seems so energy intensive at a fundamental level when you consider that the sun naturally distils and desalinates water all day long.
The process described in this article ("Membrane Distillation") seems like a hybridisation of the two techniques and the researchers have found a way to improve efficiency by concentrating heat using lenses. Why can't this concentration of heat be used in straightforward distillation and why does distillation always seem to come in second best in terms of efficiency compared to the use of membranes? Is it because of the large surface area required?
The process described in this article ("Membrane Distillation") seems like a hybridisation of the two techniques and the researchers have found a way to improve efficiency by concentrating heat using lenses. Why can't this concentration of heat be used in straightforward distillation and why does distillation always seem to come in second best in terms of efficiency compared to the use of membranes? Is it because of the large surface area required?