If Mark is right and it is TEOWAWKI time, we'll need this solar powered water purification system, which uses wind and solar power to pump and purify up to 6500 gallons each day from brackish water; the seawater version can produce 925 gallons per day. On a sunny, windy day it will provide excess energy that can be used for other purposes.
It is designed for disaster: "During an emergency, when the water supply has become undrinkable, the Spectra land-based Solar Cube units can be lifesaving. These systems are completely self-contained and portable. They can operate independent of the grid when power is down. Power can be supplied by the attached solar panels and wind generator, or by an auxiliary generator."
Installation in Pakistan
"One unit could sustain hundreds of families during a disaster. It can also provide enough excess energy for emergency disaster officials to power refrigeration for emergency medical supplies, keep a laptop online, or ensure that crisis communications equipment remains operational." More information from Spectra Watermakers via ::CleanTechnica
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