Here is a link to a phosphor ...

Here is a link to a phosphor screen. If 3 are used, then mini "speakers" could be created. And when a coil, the same as used on speakers is used, then it would be possible to project a specific frequency. And if salt ions do respond to specific frequencies which has been shown in various ways. As you can see, even one phosphor screen is some what expensive. But it would only be one part of a system. edited to add; the 2nd link is to an explanation of Maxwell's Demon. Vacuum would have a similar effect in exciting in a negative state what is used to create the vacuum. What the vacuum is acting on, such as water, would be excited particles or molecules that could perform work. This vacuum would be a Free Energy principle because when water is exposed to an extreme vacuum, it would become excited and capable of performing work. And the more work water itself does, then less energy would be required to desalinate it. And sustaining an extreme vacuum may cost much less that using 40 to 80 bars of pressure to desalinate water. As time goes by, I will detail 2 systems, one where the land itself is of value and one where no energy source is available. And if all works out for me, I will be able to try both systems. One will be for a friend of mine in Jordan where mountains are available and the other for India where Vish lives with her family. Hopefully it can be shown that working together is much better than not doing so. http://www.kimballphysics.com/mounted-phosphor-screens http://en.wikipedia.org/wiki/Maxwell's_demon