Matteo Fasano, a 29-year-old postdoc at the Politecnico di Torino, uses a metaphor of everyday life to explain the mechanism by which salt water can be turn into drinking water.

He designed this mechanism together with his colleagues of the DENERG, the Department of Energy of the Politecnico, the Massachusetts Institute of Technology (MIT) and the University of Minnesota.

A queue at the toll booth: “Let’s suppose that the motorcycle are water molecules and that cars are dissolved ions of salt, and that both are patiently waiting in the queue at the toll booth. Now, imagine that the opening of the toll booth is a meter wide: the bikes in the queue would be able to easily overcome the barrier and to get on the highway, while the cars would be forced to back down. Similarly, a membrane for the reverse osmosis allows the transport of water molecules, while blocking the dissolved salts. An efficient membrane has also a high permeability, this means that as much water as possible equal to the energy that is required for the process passes through the membrane“.

But that’s not all, because it was also thought how to make this process economical “With the heat, especially the low cost, like the sun or the waste heat of the exhaust fumes that would otherwise be wasted“.

It did not take long because this news were circling the world and then be published on October 3 on the Nature Communications.