If the first HOA Board approved the structures, there is a possible suit vs the new board under a theory of detrimental reliance. Although there are new people on the board, the board is legally the same entity and could be held liable for reneging on allowing construction.

The flaw I’ve seen in all of the water vapor condensation approaches is that they fail to provide for heat exchange directly between the incoming and outgoing air , therefore the “coolness”, essential to precipitation, imparted to the incoming air is directly exhausted, and rapidly eroded.

Ideally, there should be sufficient heat exchange between intake and exhaust air that at the pipe open ends, they are virtually at the same temperature, despite being cycled thru a chilled spot. The transition between liquid and vapor water is, absent unknown science or magic, a matter of the transfer of 970 BTU per each pint condensed. (7760 BTU per gallon)

Using a sky radiation approach to cooling your condenser core, if the latent heat of vaporization of water is 2.26 × 106 J/kg a 1 m2 radiator can provide 50 W/m2 of cooling, enough to condense 1 g of water in 45 s; 1 kg in 12.6 hr; or 1.9 kg per day. Reportedly production rates in the Southwest U.S. can average about 2 liters per day in the winter to over 6 liters per day during the summer, per square meter.” At the low end 10 m2 (1/4 acre) of radiators cooling humid air could produce 19 L of water per day. The humid air must of course be moved thru the cooling unit, and the “coolness” used to change air temperature recovered during expulsion of the “dried” air.

A commercial, powered water condenser is sold under the name Aqua-Cycle, invented by William Madison, introduced in 1992. It resembles a drinking fountain and functions as such, but it is not connected to any plumbing. It contains a refridgerated dehumidifier and a triple-purification system (carbon, deionization, and UV light) that produces water as pure as triple-distilled. Under optimal operating conditions (80o/60% humidity) the unit claims to produce up to 5 gallons daily.

ATMOSPHERIC CONDENSER DISCUSSION

At any given pressure and temperature, in a fixed volume only a limited amount of water will evaporate into vapor, the limit is referred to as the dew/saturation point. A cubic meter of normal sea level air has a mass of 1.292 kilo. A cubic meter of water vapor at sea level pressure has a mass of .804 kilo, this would occur at a temperature of 100C (212F).

At 0 C (32 F), saturation point is about 1.1 gm of water per cubic meter. A rule of thumb is that raising the air temperature 18°F (10°C) doubles its moisture capacity. This means that air at 86°F (30°C) can hold eight times as much water as air at 32°F.

Degrees C Degrees F Gram H2O
0 32 1.1
10 50 2.2
20 68 4.4
30 86 8.8
40 104 17.6
50 122 35.2
60 140 70.4
70 158 140.8
80 176 281.6
90 194 563.2
100 212 1126.4

Relative humidity is the percentage of water vapor present as compared to how much there could be at the present temperature.

Assume a Tucson fall day with a relative humidity of 7%. There is roughly 7% of 8.8 grams of water in each cubic meter of air (.616 gram). Lower the temperature to 66 F, and relative humidity doubles to 14%. Lower the temperature to 48 F, and relative humidity again doubles, now to 28%.

If we cool air without changing its moisture content, eventually we’ll reach a temperature at which the air can no longer hold the moisture it contains. Then water will have to condense out of the air, forming dew or fog. The dewpoint is this critical temperature at which condensation occurs.

But, water does not immediately change state as the temperature reaches the “right” point. The “Latent heat of condensation” (Lc) refers to the heat that must be removed from water vapor for it to change into a liquid. Lc=2500 Joules per gram (J/g) of water or about 600 calories per gram (cal/g) of water.

Specific heat is defined as the amount of heat energy required to raise 1 g of a substance by 1° Celsius. If the specific heat of air is .25 calories per gram of air per degree C change, then each degree C change in a cubic meter represents 323 calories. The specific heat of water is 1 calorie per gram per degree C. In our Tucson fall day above there was .616 grams of water in a cubic meter of air. Air and water vapor together take a change of about 324 calories per degree C. We need to lower the temperature by around 40 C, or get rid of 12,960 calories of heat to reach the dew point. An additional 379 calories of heat needs to be removed to compensate for the latent heat of condensation, for a total of 13,339 calories.

Presenting numbers for perspective. Assume a daily water need of 174 gallons (658.6 liters) – 658,660 grams of water. In a Tucson fall day, each of us would need to “wring” all of the water out of more than a million cubic meters of air (1,069,252) – a cube 100 meters on a side. If the cross section of the cooling tube is a meter, and the device operates 24/7, and the device is 100% efficient, the required flow rate is 12 meter per second. DON’T panic, that’s only about 28 mph. At that speed though, the air must stay in the chilled zone long enough for the vapor to condense.

Increasing the pressure also changes the dew point. Double the pressure and relative humidity doubles. Assume normal atmospheric pressure of 14 PSI. Pump the fall Tucson air into a tank at 28 PSI and the relative humidity inside is now 14%. Make it 56 PSI – 28%. 102 PSI – 56%. 204 PSI – 102%, and you’ve got water accumulating in the bottom of the tank.