Have these caught on in Europe?
They seem so simple to implement - no moving parts, no electricity required. Might want to put a couple of screens on the air inlets however to keep bugs and mold out...
Michael
snipped-for-privacy@gmail.com wrote in news:5d26f5d2-45ae-4c29-b3c0-dd1d4509e975 @i24g2000prf.googlegroups.com:
Would they work in a humid climate? Also, there needs to be a mechanism to control cold Winter drafts/heat loss.
I've experienced the cooling effect in a hot, dry climate - it can be dramatic.
Not sure. I thought the predominant cooling mechanism was warm air cooled by cool rocks in the underground pipe, but water evaporating would cool further too.
Shouldn't be too hard... a simple door?
In a solar chimney, or an evaporative cooler? Where?
Michael
Found in most ancient Navajo and Hopi structures in Arizona.
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Liberals are so cute. Stupid as bricks, but cute.
How effective was Navajo/Hopi HVAC engineering?
Michael
And in swamp coolers. Just watch out not to have any antique furinture or music instruments in the air stream since the moisture can cause wood to swell.
Regards, Joerg
"gmail" domain blocked because of excessive spam. Use another domain or send PM.
snipped-for-privacy@gmail.com wrote in news:24da57d6-cce0-48b3-9515-cc20e7867f35 @v1g2000pra.googlegroups.com:
In the LA Botanical Gardens, tehre is an old stable (moved to the location from somewhere else). We went there one day when it was about
103 deg outside, and inside that ond stable, it actually fely *cold*. Here is the deal: the stable area was very high, about a storey and a half. There was a partial storey of living space above it (one wasn;t allowed to go up there, so I can't couch for what the upstairs was like). On the top was an old-timey cupola - it had angled spats to keep out rain if/when it fell, yet allow hot air to escape. It was shaded inside due to the orientation (the staiway faced south, not the stalls) - I can't recall now whether thre were overhangign eaves, tho' - that was some years ago.In a hot, dry climate, it's easier to use passive cooling because water (including sweat) does evaporate and take heat form the air. When I lived there (about 15-20 inland from Pasadena), I didn't bother with the air contditioning, especially on blissfully dry days (about 5% humidity) until it reached about 95 inside, and at that, the main problem was keeping th ecomputer cool - most times I rode out the hot part of the day by setting a fan infront of one frozen salt-water block (in a container of course, and on a stand on a plate to catch any condensate - it wouldn't evaporate away, so I just refroze it every night); had a similar block on top of the machine.
A simpler form is one I learnd from growing up in NJ without air- conditioning: open teh windows in the basement on the shaded side of the house, and in the upstairs, and fans in the upstairs windows pulling air up and out of the sunny (hot) side. Or, in houses with no basements, the bottom-floor windows on the shaded side.
Tile (ceramic or stone) floors are good for hot climates, also, because they don't hold heat; if the house is on a slab, the tiles will tend to feel cool - you can have a fan situatedto blow the cool air upwards.
OTOH, here in Houston, the humidity is considered "low" when it drops below 60% - in that humidity, passive cooling doesnt' work as well becasue the water vapor itself hold heat, making it harder for the body to shed heat via sweating. You still sweat, of course, but it can't evaporate efficiently. SO, technically, humdity isn't the same as "heat' per se, but it influences how the body sheds (or doesn't shed) heat.
or
oent
True. But the evidence you cite is flawed - you've snipped the thread to attribute a perfectly sensible quote from Joerg - whose head works fine - to Jim (whose doesn't - at least on most subjects outside electronics, though his actual contribution to this thread is uncharacteristically correct).
Far be it from me to decry any criticism of Jim, but in this case we should be lauding his occasional competence in the hope of encouraging him to do better - these opportunities are few and far between and it would be a pity to miss any of them.
-- Bill Sloman, Nijmegen
Everyone wants a permanent "woody" ;-)
Because I actually happen to be somewhat of an expert on evaporative coolers... building a bunch of experimental types from 1980-83 ;-)
If you're willing to commit enough area (in your backyard) to evaporative cooling, it can approach A/C dryness at an operating cost of 1/5 that of A/C.
Tour some Navajo and Hopi ruins to see the basics.
I still have the files if anyone wants to drop by.
What a TURD you are ;-)
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Al Gore is the Pied Piper of "Climate Change"
Soothing you with Bull Shit
While quietly sucking the IQ out of your head
Similar here, sans the ice block. The office often reaches 95F and it doesn't bother me.
After I laid tiles it got worse: They store the heat and after cooling the house to 80F before turning in they heat it right back up after closing the windows. Ok, they are laid on a 2" mud bed which doesn't exactly help.
I have a client there and sometimes when I get proto-units there is liquid rust (!) oozing out of stainless steel hardware. Couldn't believe it. They said it's rather normal there.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
Joerg wrote in news:8D1jk.18668$ snipped-for-privacy@flpi146.ffdc.sbc.com:
But how does your computer fare? Mine have always run hot when I do 3D (yes, teh dreaded CGI ) becasue it streasses both the CPU, and the graphics-card memory, so it gt sluggish and "cranky" when the temp hit about 88 deg F.
Me, tho' I could actually go out and dig up the yard when it was in the
90's, and go for walks even into the low 100's, as long as it was dry out (I just always carried a large bottle of dilute OJ with a pinch of salt). What levels me in Houston is the humidity.Oh...! THere are probably more variables than I realize. ALl I can say is that the house here is on a slab on top of clay ("active soil", has to be kept moist becasue, if it dries out, it shrinks like crazy and will crack your foundation and badly skew your house), but my tiles always feel pretty cool. Of course, I *am* a slug and use air- conditioning, but even when I lived in CA, tile always felt much cooler than carpet.
Yup, pretty much. Wood rots really fast, also, which is why I'd glad that the upper level of this house is at least Hardi-Plank (lower level is brick). I also paid extra to have TyVek between the sheathing and the outer materials - it adds a bit more isolation between the outside humidity, and the framing/interior materials (tho' it still gets pretty humid inside). THat bit of additional isolation, tho', along with the TechShiled in the roof, do definitely help reduce the electrc bills (highest cost is air-conditioning, not heating). Now, if only the HOA would allow solar, and some modesty-sized PacWind-type vertical wind turbines... ;)
Seriously, tho', humidity is an important consideration when planning passive cooling, because it's not only a matter of whether the techniques will work in high humidity, but also, how well will the materials (that are used in the system) hold up.
In Arizona, solar trumps HOA's
Wouldn't work here, at least where I am, in Arizona. It's dead calm to a few MPH around here most of the time.
Get a deep enough cave ;-)
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
The Democrats lost their souls a long time ago.
It must have happened when they had their spines removed.
[snip]
Though the airport is reporting 8MPH right now. Is that enough to extract useful energy?
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Liberalism is a persistent vegetative state
=46rom the OT: Atheist Joke thread on Mar 29 2006
"Since you have exhibited extreme anti-American behavior here in this newsgroup I simply pointed out said behavior to ICE and a few of my friends within the FBI.
By your own mouth you are a terrorist."
Quite why he thinks I'm a terrorist, I've never worked out - he certainly never bothered to post the quote to which he imagined he was referring. And his idea of extreme anti-American behaviour must refer to my pointing where American society falls sort of perfection - which is scarcely anti-American, unless you have to be a rich Republicans to be "real" American - and their short-sighted social policies don't even work to their own advantage in the long run.
-- Bill Sloman, Nijmegen
Blather all you want, lets see you get thru security...
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Liberals are so cute. Stupid as bricks, but cute.
control cold Winter drafts/heat loss.
The solar chimney will work OK on the very rare days when the UK has enough sunshine to drive it. Yesterday was one of them. Wind based passive ventialtion is a lot more effective here. We have plenty of that.
But for airconditioning the UK only really needs it for badly designed all glass office buildings (and power hungry computer suites). Most homes don't need it at all. In continental Europe there is a bit more of a case especially further south. But living in Belgium I never found a need for it. Living in Japan it was essential although I found
26C and reduced humidity to 70% about the most comfortable setting when outside was >38C and 95%+.The UK BRE (Building Research Establishment incorrectly called "British") is quoted in the Wiki article as having been designed to utilise the solar chimney. And there are quite a few modern office blocks with more sensible, less greenhouse like properties in summer and better behaviour in winter with passive ventilation.
Yesterday was the hottest day of the year here with 28C peak outside. My house has such thick walls and huge thermal inertia that by the evening the interior temperature in the hottest part had just about reached 24C. Windows open in the evening allow it to cool at night. Today the sun has not yet burnt through the sea fret at 10am.
So the domestic need for aircon isn't significant. We may get a dozen days that warm in a year if we are lucky. And usually for no more than a week at a time. Yesterday was the first Saturday this year where it did not rain on village fetes and festivals in my area.
UK is not a hot dry climate. It is a mild damp one and a long way north.
Regards, Martin Brown
I don't think going from 15% humidity to 30-40% or whatever preffered humidity is going to do much. They used to call them air conditioners. Stores would then advertise they had refrigerated air on the front door.
greg
In , Martin Brown wrote in part:
You don't get that anywhere. The world record for dew point in the atmosphere (on a weather scale, as opposed to something localized like above a pot of boiling water) is 35 C. That occurred in Saudi Arabia. Dew points past 30 C tend to be mainly around the Red Sea and Persian Gulf.
Too many people remember what the RH was in the morning and then think it stays there when the temperature goes up 10 degrees C or more as the day goes on.
- Don Klipstein ( snipped-for-privacy@misty.com)
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