Water in dry areas is a problem. Often these areas border the ocean which is an obvious source of water if only we could get the salt out. Renewable energy is usually available in multiple forms since arid regions usually have a plentiful supply of solar energy. Wind energy is usually plentiful where oceans and deserts meet and the ocean can provide both wave and current based power.
Understanding the market
Many people could benefit from this who live in dry areas or areas underserved by water supply systems. Disaster relief is a possible use.
Project goals
Let's start on a small scale: one desalinization plant suitable for a third world village of say 200 people (feel free to change this number if you wish.) We can scale up later. If the plant floated just offshore to take advantage of wave and/or current power that would be great as it would make the plant easily towable to where it is needed and useful for disaster relief. We want to be as ecologically friendly as possible so use of chemicals added to the water should be eliminated or at least minimized. Harm to sea life should be minimized at the water intake and waste water outflows. We also want to conform with applicable regulations.
Design
We don't want to prematurely solidify the design on one idea so let's throw out some ideas on the discussion page. Splitting into several alternative designs is okay too.
Discussion
Cleaning water of other unwanted substances is also possible. We don't want to remove minerals/or other good stuff unless absolutely necessary but we do want to remove anything toxic. Since solar powered distillation is the obvious solution, perhaps minerals could be added to drinking water after distillation.
Next steps
Let's make some design suggestions.
Conclusions
It is early times: no conclusions yet.
Anyone who has any thoughts or would like to help design this project is invited to contribute either on the discussion page or below.
References
http://en.wikipedia.org/wiki/Desalination
http://en.wikipedia.org/wiki/Peak_water
http://en.wikipedia.org/wiki/Water_security
http://en.wikipedia.org/wiki/Solar_still
http://en.wikipedia.org/wiki/Solar_desalination
http://en.wikipedia.org/wiki/Membrane_technology
http://en.wikipedia.org/wiki/Nanofiltration
http://en.wikipedia.org/wiki/Seawater_greenhouse
http://en.wikipedia.org/wiki/Integrated_Biotectural_System