Air conditioning

Submitted by evets on 21 November, 2006 - 10:10.

As promised I have been looking further into eporative air conditioning. This used to work well only in hot dry climates where the latent heat of evaporation cooled the incoming air (basically an evaporative system draws outside air over a 'wet towel' - the water evaporates from the towel and cools the air). Now a lot of work has been done on solar regenerated dessicant (like silica gel) which absorbs moisture from the incoming air making evaporative cooling efficient even in Nica type hot + humid climates. A schematic is here

http://www.americansolar.com/SolarDesEvapCycle.pdf

These systems are at least 80% more efficient than conventional refrigerant based air conditioners.

Another interesting point is the use of DC motors for the fans etc - a DC motor is three times more efficient than an AC one.

I'll be looking at a DIY version of this a/c unit over the next few months.

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that's a nice delta between the . . .

Submitted by webtrainer on 21 November, 2006 - 15:15.

outside and inside temps, 20 degrees!

there is a general passive cooling page to look at here.

Doors of hope fly open when doors of promise shut. -Thomas D'Arcy McGee

great work!

Submitted by Che Guevara on 21 November, 2006 - 10:51.

thanks for looking into this. you deserve a promotion! calling john wayne, i recommend this nicalivinger for promotion.

I second that

Submitted by Former NL Member on 21 November, 2006 - 11:46.

Evets could be promoted to Mr. Cool, the Chillmeister, or something appropriately silly yet appropos.

And to add

Submitted by toms on 21 November, 2006 - 16:45.

My 2 cents I third it...

Hey this is absolutely great and the moisture then returns to earth as pureifyed water later on down the chain...Koolman

Lyin' Farmer John Wayne

is that the

Submitted by Che Guevara on 21 November, 2006 - 18:08.

promotion? KOOLMAN!

Source article

Submitted by evets on 21 November, 2006 - 10:16.

I forgot to include the source article for the schematic

http://www.eere.energy.gov/femp/newsevents/fempfocus_article.cfm/news_id...

an over complex bit of 'energy saving' which must have cost a fortune but the source of some useful links.

I can't spell evaporative either.....

Goood info!

Submitted by RichMcClure on 21 November, 2006 - 11:13.

That's quite a guard shack. Great exposure, to functionally display renewable technologies at the foot of the Pentagon, I love it.

RichMcClure

Thanks all

Submitted by evets on 21 November, 2006 - 11:54.

I'll be back !! A cool beer for me please in the meanwhile

great! ok where do i go

Submitted by Che Guevara on 21 November, 2006 - 15:01.

to get one. on a serious note, who will be likely to go forward on this idea?

me too!

Submitted by dirtbag on 21 November, 2006 - 18:51.

Where might one call to have same installed!

I will take this further

Submitted by evets on 22 November, 2006 - 02:26.

I own a small prototyping company in the UK. We can make almost anything. It looks to me like the only difficult bit is 'the wheel' - a disc of drying agent which slowly rotates so half is in the air supply while the absorbed moisture is baked off the half not in the airstream by solar heat.

The example in the diagram is over complex, I don't see a need to have the heat collecting tiles and hot air supply to dry the wheel in a tropical country, I think it can be dried in a more direct way.

The absorbent disks are becoming available on the open market as replacements for commercial units (lifetime seems to be several years) and that is the only bit not amenable to DIY.

I assume anyone who wants to make a unit could cope with finding blowers and flexible ducting and put the thing in a box so all that-s needed is a simple solution to the 'wheel'- at the moment I'm thinking of a bicycle wheel to support the disk driven by a tiny motor driving via a belt running in the tyre groove but I'll get hold of a real drying disk and work something out.

It will take a while, after Christmas I should think, but I'll be back!

Perhaps we should ask for an 'Alternative Energy' forum heading to pull together wind generators/pumps, solar ice makers, air co and everything else, it would certainly help me.

are you going.....

Submitted by Che Guevara on 22 November, 2006 - 14:41.

to design your house with this evaporative cooling idea in mind? john is an architect and maybe able to help?

If I can afford

Submitted by evets on 22 November, 2006 - 14:57.

his (no doubt) exorbitant fees I will. My plan is to get a really nice palapa in place (see my Granada pictures post) and use that while the house takes shape.

I can do a lot of work on the AirCon while still in Europe but, of course, the trick is to make it work with materials available in Nica.

Maybe Two Tonas

Submitted by Former NL Member on 22 November, 2006 - 15:45.

and I've been known to barter for services.

Coupla points

Submitted by no longer registered on 22 November, 2006 - 15:06.

I don't think John would work for my standard fee of one cold Toña but I don't think he'd clean you right out! However, pay me -- skip the middleman: http://www.palapakings.com/ [sorry John, you can't win them all ;~) ]

Second point: I am familiar with the term of palapa, but can only remember hearing it in Mexico. Everyone I know in Nicaragua (and CR for that matter) call them: ranchos. Is that another example of Nica-speak or just different folks for different strokes?

It"s my Caribbean background

Submitted by evets on 23 November, 2006 - 02:06.

man, everbody dun call dem ting Palapas were I keeps me boat.

i like the way you think.....

Submitted by Che Guevara on 22 November, 2006 - 14:59.

i like that idea of a palapa inplace and then build the house. i will have to follow your lead. hang in there.