These are initially appealing options which didn't pass rigorous proofing.
Waterseer (www.waterseer.org) is presented as a simple, low-tech device to harvest safe drinking water from the vapor in the air. Originally designed for drinking water, the principle is now advocated for use in combination with micro-irrigation, which would have the advantage of producing salt-free water. In an article from the Guardian it is stressed that such a solution may not be the most appropriate in all cases, and that systemic approach is required. But more importantly some have gone through the numbers in terms of thermodynamics and showed why the system can't work.