How air conditioning works
and why hot air is a problem.
Cool-n-Save solves a big problem for all modern central air conditioning systems: extreme heat. The fact is, most conventional air conditioners are unable to effectively transfer their stored heat into the surrounding air. They work harder and longer to cool the air in your home. As a result, they shorten their lifespan and produce unreasonably high electric bills.
To combat this problem, large commercial AC users such as commercial factories, warehouses and office buildings install professional misting systems around their AC condensers. They’ve been doing this for decades. These systems are much like the misters you encounter in restaurant patios and amusement parks. And everybody uses misting for much the same reason: it cools the air.
Air conditioning 101: explains everything.
To understand how misting works for air conditioning system, you have to understand it’s single biggest weakness. Modern “split system” central air conditioning (prevalent in residential and commercial properties) still feature the same basic design that Willis Carrier envisioned when he invented air conditioning back in 1902: copper tubing filled with refrigerant gas with most of the tubing gathered at either end into what are called condensing coils.
Aluminum fins welded to the copper tubing facilitate heat exchange as air is blown through the coils. The “split” is in reference to the configuration of the coils — one set placed outdoors so that the system can cool the refrigerant; a second set is placed somewhere within the system ducting to cool air as it is blown into the building.
The problem: getting rid of heat.
Engineers measure the rate of heat exchange in terms of what they call ‘heat flux’. In the case of your air conditioner, heat flux is most efficient when outdoor (ambient) air temperature is lower than the refrigerant inside the coils. That’s why the “ideal” outdoor temperature is so important. And remember – we’re talking about ambient temperature, not the radiant heat that’s beating down on the AC equipment. Heat flux in this system is most efficient when outdoor AIR temperatures are at or below 85°F (Fahrenheit). What happens when ambient air temperatures rise above 85°? It’s pretty simple rule of thermodynamic: efficient heat exchange becomes increasingly difficult. Your AC system has to work harder and harder to maintain the demand to keep your home cool.
Now you know why during the hottest days of the summer your local electric company asks you to keep your thermostat set to a balmy 78°F. When the ambient outside air rises, your central air conditioner loses efficiency. It’s as simple as that. Without some help, the air conditioning system can’t keep up and the system breaks down. You can try to put some shade on the outside condenser, but the key is AMBIENT air temperature. Not RADIANT temperature from direct exposure from the sun.
How Cool-n-Save solved the problem.
The inventors of Cool-n-Save solved the “hot air” problem by injecting water mist into the air around the outdoor coils. Most of the mist evaporates in a “flash” and the air around the AC unit cools immediately – by as much as 30°F.
What happened? Engineers call it “adiabatic saturation”: where heat is instantly absorbed by water mist and released when the water evaporates. Heat is literally sucked out of the air. The flash evaporation effect is well-known. It is the reason why the air around breaking waves on the beach and waterfalls tend to be much lower than elsewhere. It’s why amusement parks and sporting events spray mist to help lower air temperatures.
The result of this constant, immediate evaporation produces a substantial drop in ambient temperature without wetness. The air temperature near a misting system is automatically lowered by as much as 30 degrees. This is what our inventors came to call the pre-cool shield.
“Pre-Cool” Shield equals Greater Cooling Power
Inside the ‘shield’, the air temperature can be 30 degrees lower than surrounding air. For instance, if the ambient air temperature is 98°, Cool-n-Save mist will knock it down to approximately 68°. According to a white paper published by Colorado Springs Utilities in 2005, for every degree Fahrenheit reduction in ambient air temperature, a reduction of 1 to 1.5% in energy demand is gained.
Thus, cooler ambient air dramatically increases the EER (Energy Efficiency Rating) of the air conditioning system. The system runs more efficiently and less frequently, thus less energy is used for GREATER cooling power.
Cool-n-Save has passed all tests.
Third-party tests have shown that Cool-n-Save Evaporative Pre-Cool Systems produce up to 30% savings on energy use; the average is around 26% depending on climate, and the conditions and size of the system (the larger the system, the greater the potential energy savings). Cool-n-Save also helps reduce wear and tear on equipment (thanks to gained efficiency) which leads to lower overall cost for repair and replacement.
A detailed analysis of Cool-n-Save was conducted by the Department of Mechanical Engineering at Tulane University in Louisiana in 2005. In the 29-page report, researchers concluded that Cool-n-Save substantially increases heat transfer of air conditioning units. A separate study presented in 2009 during an international conference held in Glasgow, Scotland by researchers from Hong Kong Polytechnic University confirms that the application of water mist to pre-cool ambient air increases performance and efficiency of air conditioning systems by 30% or more.
And that’s how Cool-n-Save earned a TechAmerica High-Tech Innovation Award for Green Engineering from Harvey Mudd College. And that’s how Cool-n-Save can significantly reduce energy consumption wherever air conditioning systems are used.
Maybe it’s time to get one for your home?
Links to studies:
Colorado Springs Utilities White Paper
Evaporative Pre-Cooling of Large Air-Cool HVAC Equipment
Tulane University Study
Improvement on the Efficiency of Condensing Units
Hong Kong Polytechnic University
Application of Water Mist Pre-Cooling on Air Cooled Chillers
As outside ambient (air) temperature rises, your central air conditioner loses efficiency. Without some help, the system can’t keep up.
You can put some shade around the condenser, but remember – the problem is ambient heat, not radiant. Cool-n-Save creates a “Pre-Cool Shield” in the air around your AC unit. Inside the ‘shield’, the air temperature can be 30° lower than surrounding air. If the ambient air temperature is 98°F, Cool-n-Save mist will knock it down to approximately 68°. The system can work efficiently, even on the hottest days.