New Air Conditioning System Has Potential to Slash Energy Usage by Up to 90 Percent

[Ed Barrow]

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.

"The idea is to revolutionize cooling, while removing millions of metric tons of carbon from the air," NREL mechanical engineer Eric Kozubal, co-inventor of the Desiccant-Enhanced eVaporative air conditioner (DEVap), said.

"We'd been working with membranes, evaporative coolers and desiccants. We saw an opportunity to combine them into a single device for a product with unique capabilities."


http://www.sciencedaily.com/releases/2010/06/100621071943.htm

[gateley]

1. Excellent!! nt

[HughMoran]

2. My tax dollars at work

Good news.

[WhiteTara]

3. too bad it's 2 or 3 years away

from production! I want one NOW!

[Blubba]

18. More than 2 to 3 years away.

The article said NREL was going to spend 2 to 3 years perfecting the process and miniaturizing the components. Only then will it try to license the technology. It may take several years for a manufacturer to design and thoroughly test a unit of their own to sell.

Call me cynical, but having read plenty of press releases in my day, they always emphasize the good and downplay the bad. For starters this technology relies, in part, on evaporative cooling. Anyone who has used devices that evaporate water, like humidifiers for use in the winter, knows they are prone to developing scale deposits. That means annual or more frequent maintenance. I'm sure NREL is running its device using demineralized water on its prototype to avoid this. Time will tell if they can develop this into something that will work in the real world.

Sorry to sound like a wet blanket. I really hope this is the real deal. But it is almost expected in research to put the best spin on your results and try to capture the public's imagination, the better to secure grants and funding to continue working.

[Hello_Kitty]

4. Awesome! eom

[msongs]

5. great maybe then my solar on the roof will run the AC too. now the AC is too much of a hog nt

[dkf]

6. Doesn't work in humid areas? Darn.

[theophilus]

7. No Darn required. It works great in humid areas. If it will just make it to market.

[eridani]

13. Probably the dessicant will need to be changed more often where it's humid. n/t

[struggle4progress]

14. Then one needs an energy efficient way to recharge the dessicant

Otherwise the whole scheme collapses

[madokie]

15. Without knowing for sure I'd say heat is what does that

again with out knowing for sure I'd say that is part of the reason for the high efficiency of the unit. For every pound of water evaporated around 1200 BTU's are removed.

[struggle4progress]

16. My point is this:

An evaporative cooler works very well with dry air

Here, dry air is produced by demoisturizing air with a desiccant

But the efficiency of the whole system overall must then take into account not only the evaporative cooling; it must also take into account the energy costs of restoring the desiccant

So, in a humid climate, you run air over a desiccant to dry it; perform evaporative cooling and rehumidify the air; but once you have damp desiccant: if you set out to remove the water by evaporating it from the desiccant, I think you require at least an energy input equivalent to the cooling advantage you got by dehydrating with the desiccant. That doesn't mean the idea completely stinks -- for example, it might be possible to dehydrate the desiccant on-site in a solar oven -- but it does mean that some thought is needed is make sure the process is actually advantageous

[LiberalEsto]

8. This system removes the humidity in the air

as part of the cooling process. I can hardly wait to see these become available to residential customers.

[glinda]

11. If it is affordable. Many things people would buy if they were affordable.

[JoeyT]

9. How useful this will be depends on a ton of factors.

There have already been huge leaps in technology that manufacturers don't use as it is because it might shrink their profit margin.
Reciprocating compressors are still the most common kind even though a more efficient compressor was invented in 1905. (The inventor was thinking of steam engines, not ACs). Reciprocating are just cheaper to manufacture and have to be replaced more often.

There's also a question of how effective they are without continuous maintenance. The most efficient ACs around today will more or less stop working entirely when the filter or coil are dirty. And that's a really common problem.

Don't get me wrong: This is great news, but only if they can find a way to make it cheap enough people can afford it and low maintenance enough that people can't screw them up.

[Blubba]

19. As I indicated in a different thread,

since the technology relies partially on evaporative cooling, that means it needs a constant supply of water. As water evaporates it leaves scale behind (unless you use demineralized water, which you can bet NREL is using on its prototypes). In the real world I suspect the units may need frequent maintenance, which if not too onerous would be an acceptable tradeoff considering the potential cost savings.

[JohnWxy]

10. recommended!

[SocialistLez]

12. I'd love for these to be made in the U.S. once they become commercial available. NT

[femrap]

17. I want one

NOW!