We have no airco, that's the cheapest way :P

How About 90% More Efficient Air Conditioning?

Photo: Pat Corkery/NREL

The National Renewable Energy Lab has Done It!
As Lloyd and other sensible people keep pointing out, if our buildings and cities were better designed, we would need a lot less air conditioning, and in many cases none at all. That should be goal #1. But because it's doubtful that's ubiquitous A/C is going away any time soon, it can't hurt to make the technology more efficient (keeping buildings cool is using about 5% of the energy used in the US). That's exactly what the engineers and scientists at the National Renewable Energy Laboratory (NREL) have done.

Image: NREL

The U.S. Department of Energy's National Renewable Energy Laboratory has invented a new air conditioning process with the potential of using 50 percent to 90 percent less energy than today's top-of-the-line units. It uses membranes, evaporative cooling and liquid desiccants in a way that has never been done before in the centuries-old science of removing heat from the air. (source)

This is Going to be Huge Someday
The problem with most evaporative cooling A/Cs is that they only work well in dry climates and add humidity to their cool air output. The NREL's technology, which they call DEVap, solves that problem by using liquid desiccants to remove the humidity from the air that has been cooled down. Combining those two things isn't new, but nobody has quite made it work well so far. Until now, that is.

And the energy savings aren't the only benefit of DEVap.

Because DEVap uses salt solutions rather than refrigerants, there are no harmful chlorofluorocarbons (CFCs) or hydrochlorofluorocarbons (HCFCs) to worry about. A pound of CFC or HCFC in refrigerant-based A/Cs contributes as much to global warming as 2,000 pounds of carbon dioxide. A typical residential size A/C has as much as 13 pounds of these refrigerants.

NREL is planning to keep improving the tech for a few years, and then license it to industry. So don't expect to see commercial versions of the DEVap for a few years...

Via NREL, Technology Review

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