If you take a look at How Air Conditioners Work you can see that a typical air conditioner is a very simple thing. It has an electric motor that runs a compressor, and everything else in the system is passive – tube on the hot side and cold side, plus an expansion valve.
The only problem with the existing system is that the electric motor needs a lot of electricity to spin the compressor. In the summertime, a sizable portion of the power grid is dedicated to feeding the electricity needs of air conditioners.
There is an alternative known as evaporation cooling (sometimes called swamp coolers). They rely on the temperature drop that occurs when water evaporates, and they are especially effective in dry climates as described here:
There is no doubt that evaporation cooling uses a lot less power than standard air conditioning (assuming water is plentiful). The problem with a swamp cooler is that is makes the air humid. If you live in the desert that may not matter, but in any humid location it will sometimes rule out a swamp cooler.
The new air conditioner idea takes the benefits of evaporation cooling and then cleans up the humidity problem with desiccants, as described here:
Most people know of desiccants as the pebble-sized handfuls that come with new shoes to keep them dry.
The kind NREL uses are syrupy liquids — highly concentrated aqueous salt solutions of lithium chloride or calcium chloride. They have a high affinity for water vapor, and can thus create very dry air.
The article goes into detail on the use of the desiccants in this system. The bottom line is that, if the system can be perfected, there could be a huge reduction in the cost of operating an air conditioner. There would also be a huge impact on energy demands in any big city during the summer.
For more information on The National Renewable Energy Laboratory (NREL) see:
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