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Q & A: making water with solar power?

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Most recent answer: 08/31/2011
Q:
Hello, I have just seen some questions to your site from kids. I have often envisaged a small, solar powered machine that sucks in Hydrogen and oxygen from the air and combines them to create water. Not water vapour being sucked in, nor distillation. Not thousands of gallons. Just a trickle would do. Is that feasible? Steve
- Steve Read (age 62)
Ottawa ON CANADA
A:
There's very little free hydrogen in the atmosphere. On the other hand, there's usually quite a bit of water vapor. That's no mystery- at room temperature the chemical equilibrium strongly favors combining hydrogen and oxygen to make water.

So if you need to extract a trickle of water from the atmosphere, it makes sense to extract the water itself, rather than to try to use the tiny traces of free hydrogen. A solar powered device could cool a coil, just as in a commercial dehumidifier, collecting some water that would provide your trickle. In fact, you could use some commercial solar panels and electronics to make ac power to power a commercial dehumidifier, and just use the output water from it. A more miniature device could be made using the dc power from a small solar panel to drive a thermoelectric cooler and a small fan.

Mike W.



(published on 08/31/2011)

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