Efficient Air conditioning discussed

Will the answer to lower energy, efficient air conditioning systems come from the computing industry?

The big increasing number of data centres that house computer servers could be among the first to benefit from some of these developments in cooling technology. These data centres use a lot of energy. IBM reckons that in some centres about half of all the electricity consumed is spent cooling equipment. Mr Collins’s company, Synergetics, is working on what it calls a “surgical ventilation” system which uses small tubes with fans that whisk heat away from hot components inside servers before it warms nearby parts. This heat could then be used to power thermal air-conditioning. And, of course, the fans will be aerodynamically perfect.

(eg. If blades were designed for better aerodynamic efficiency, instead of for being stamped from sheet metal as cheaply as possible, the electricity consumption of many cooling systems could, he says, be cut by a third. )

Or again "Nature's best-Water beats all contenders"

Evaporative coolers are a cheap alternative to refrigerative air-conditioning. The air near a splashing waterfall or fountain is cooler than the surrounding area because water droplets remove heat as they evaporate. Spraying water inside a cooling tower while air is blown through will have the same effect. Whereas refrigerative systems reduce the humidity of air (because some water vapour condenses and is drained away), evaporative coolers increase humidity. This means they tend to be more popular in dry climates.

However, researchers at the National Renewable Energy Laboratory (NREL) in Colorado have designed an evaporative system that sprays ambient-temperature water into warm air to cool it, but in a way that also lowers the humidity. NREL uses syrupy liquids which contain salty desiccants to soak up the humidity. Hot water is used to heat the syrups and dry them out. NREL’s technology, known as “desiccant-evaporative cooling”, is still being developed, but it requires little power, not least because the hot water can be obtained from solar panels. Ron Judkoff of NREL thinks the process will consume only about a fifth of the energy of conventional air-conditioners, depending how dry the climate is to begin with.


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Water beats all contenders"

Product	Latent Heat of Evaporation *)
	(kJ/kg)	(Btu/lb)

Water

2257

970.4