CWO4GUNNER
Well-known member
With all the talk about efficiency why hasten any AC companies found a way to create a system that automatically switches from AC to evaporative cooling automatically since evaporative cooling is 5-10 times more efficient than traditional AC “WHEN” conditions are right. I'm so tired of having to check the local weather forecast for Barometric pressure, Dew Point, and Humidity. Then go through the agony of switching between AC to Evaporative cooling by powering up and down, opening and closing vents and windows and turning water supply on and off.
Living in SW Arizona we have an unusual summer season, always hot but different based on the dew point and humidity. Summers always start out very dry here with a low dew point and humidity around 11%. This is when I turn on my 5000 CFM evaporative whole house cooler. This simple machine comprised of a blower fan and three 24x48 inch intake panels filled with wet straw, is able to make a temperature difference between the intake outside air and exhaust air into my home of approximately 40-50F drop in temperature. Amazing when you consider that the supply water in summer here is between 80-90F and the outside temperature is 100-120F, how is it possible for me get a temperature measurements of 52-58F coming off the exhaust grill inside the house, all while using only a 10th of the energy required to power my central AC unit? I will just say that it is only possible while there is a high pressure atmosphere, low dew point and low humidity can this miracle occur. The high pressure atmosphere acting as the compressor with its high pressure dry air is drawn in and catapulted by the blower fan through the wet straw intake panels acting as an evaporator. The high pressure dry air colliding with the water molecules respond like a refrigerant and undergo a rapid change of state from a liquid to a high volume gas resulting in a rapid temperature drop within and exiting the evaporative cooler exhaust vent. This happens according to Boyle's Law PV=K, where P is the pressure of the gas, V is the volume of the gas, and k is the temperature.
Only one big problem! As soon as monsoon season hits in SW Arizona where the atmospheric pressure drops (no compressor), the dew point rises, and humidity increases the effect of cooling drastically diminishes. With almost no change of state of the water inside the evaporative cooler from a liquid to a gas, Boyle's Law PV=K almost stops. Because there is almost no gas pressure (P), almost no gas volume (V), and almost no temperature change (K).
Living in SW Arizona we have an unusual summer season, always hot but different based on the dew point and humidity. Summers always start out very dry here with a low dew point and humidity around 11%. This is when I turn on my 5000 CFM evaporative whole house cooler. This simple machine comprised of a blower fan and three 24x48 inch intake panels filled with wet straw, is able to make a temperature difference between the intake outside air and exhaust air into my home of approximately 40-50F drop in temperature. Amazing when you consider that the supply water in summer here is between 80-90F and the outside temperature is 100-120F, how is it possible for me get a temperature measurements of 52-58F coming off the exhaust grill inside the house, all while using only a 10th of the energy required to power my central AC unit? I will just say that it is only possible while there is a high pressure atmosphere, low dew point and low humidity can this miracle occur. The high pressure atmosphere acting as the compressor with its high pressure dry air is drawn in and catapulted by the blower fan through the wet straw intake panels acting as an evaporator. The high pressure dry air colliding with the water molecules respond like a refrigerant and undergo a rapid change of state from a liquid to a high volume gas resulting in a rapid temperature drop within and exiting the evaporative cooler exhaust vent. This happens according to Boyle's Law PV=K, where P is the pressure of the gas, V is the volume of the gas, and k is the temperature.
Only one big problem! As soon as monsoon season hits in SW Arizona where the atmospheric pressure drops (no compressor), the dew point rises, and humidity increases the effect of cooling drastically diminishes. With almost no change of state of the water inside the evaporative cooler from a liquid to a gas, Boyle's Law PV=K almost stops. Because there is almost no gas pressure (P), almost no gas volume (V), and almost no temperature change (K).
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You can run from Houston the The Big Easy and it feels like you're in the same town.