New Air Conditioner Process Cuts Energy Use 50-90%

necro81 writes "The US National Renewable Energy Laboratory has announced that it has developed a new method for air conditioning that reduces energy use by 50-90%. The DEVap system (Desiccant-Enhanced eVaporative air conditioner) cools air using evaporative cooling, which is not new, but combines the process with a liquid dessicant for pulling the water vapor out of the cooled air stream. The liquid dessicant, a very strong aqueous solution of lithium chloride or sodium chloride, is separated from the air stream by a permeable hydrophobic membrane. Heat is later used to evaporate water vapor back out — heat that can come from a variety of sources such as solar or natural gas. The dessicants are, compared to typical refrigerants like HCFCs, relatively benign on the environment."

Comments

Good for server farms?

[tagno25]

Heat is later used to evaporate water vapor back out — heat that can come from a variety of sources such as solar or natural gas.

or the servers that are being cooled?

Dr. John Gorrie

[dtmos]

Few people have heard of the true inventor of both air conditioning and the artificial ice machine, Dr. John Gorrie, of Apalachicola, Florida, who received the first patent (number 8080) for a machine to make ice, on May 6, 1851. While it was reduced to practice (he used it to cool the rooms of his fever patients, and gave iced drinks to his guests at parties -- a fantastic novelty in 1850s Florida) he was unable to make a financial success of the venture. His machine was the first to make use of the refrigeration method of air conditioning.

Re:Is this a closed system?

[SharpFang]

1) it can use salty water. It's drinking water that we are short on.
2) cooling the air extracts humidity from it. If the dehumidifier filter is ~99% efficient, it will receive more water from intake air than lose at the filter.

Re:lithium chloride or sodium chloride?

[Anonymous Coward]

You need to do more research. You can put R-400 in the walls and it won't help, because you are dealing with a building that has windows and occupants.

In most places, solar heat gain is a major component that A/C has to deal with. Humidity in the makeup air is also a large problem for A/C to handle.

Humans inject heat and water vapor into the building through cooking, respiration, appliances, and opening doors.

Humans also need fresh air, and you can't -- legally or practically -- build an air-tight building without makeup air.... which introduces more humidity and heat into the building envelope.

I built my house 2 years ago and used all closed-cell spray foam (isocyanate) making all walls, floor, and roof, water-tight and air-tight. 133 mm of foam gives me R-37 in the walls, and more gives me R-60 in the floor and ceiling. All ducting is in conditioned space. All external walls have thermal breaks (offset studs). I have an ultra-efficient water-jacketed earth-coupled geothermal heat pump. The solar gain in the summer still rapes my house with heat gain. The makeup air I have to have because the house is so damn air-tight, uses a high capacity heat exchanger, but still is a water-vapor sieve pumping water vapor into the conditioned space that the A/C has to then remove.

So do a little more research before you spout off with drivel.

Re:OK, so when can we buy one?

[Spazmania]

can't tolerate it mentally.

That's about right. I program computers for a living. Deep concentration for long periods of time is a key skill. Above the mid 70's I find it difficult to concentrate.

Then there's the humidity. The summer humidity around here is routinely 70%. I own a lot of expensive electronics. 70% plus heat is ruinous. Rust and corrosion. Oxidation. I'd lose half the electricity savings to early failure of my electronics.