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Ok, trying to make sense of those numbers.

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Water is clearly indicated as daily production. 750 g of water per square meter per day, means that 2 square meters can sustain the drinking water of a person, if you also want to wash and cook, you may want to scale up, still not too shabby if you pave a roof of it a family can probably get enough to be self sustaining... my only qualm is that this will not be drinking water probably, unless you can assure it is free of contaminants and add minerals I guess.

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For the electricity part as far as I understand the 685 mW are the average instant production in day time. This probably rounds down to about 4Kw/h per square meter per day, which if I understood correctly, is not too shabby, again a decent roof mounted installation could easily cover the needs of a family.

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Sooo... where is the catch? There must be a catch...

EDIT: as u/AnimiLimina ponted out, the catch is that I got lost between Watts and kiloWatts, I got carried away by the wish fir this to be a game changer apparently (watever, it remains a stupid mistake, sorry everybody).

It's going to be money. The catch is always money.

Sometimes, it's the second law of thermodynamics.

If I’m not mistaken you jumped a magnitude there somewhere… 685 Milliwatt are 0.685 Watt. If we say 12h of production that comes out to 8.2 Watt Hours. A kWh is 1000 Wh. It’s just a little fart of electricity.

And the question as always is what are the conditions that create the 750g water. I can guarantee you it’s not dry dessert air.

Yep, i did exactly that. Ok, so we are down from "sustaining a family" to "keep phones charged".