Cool tubes

[glenn kangiser]

I'll bite on this one, JRR.

I drilled wells for about 10 years.  A variation of the method you are talking about is usually done with two wells -one for cool water and one for disposal of the water after the coolness or heat is taken from it by a heat pump.  

It sounds to me like you are talking about a version of a swamp cooler recycling air down two pipes in the well - I don't know how well that would work - once all the air was saturated with moisture you would loose the cooling effect it seems.  The well water being fairly static may increase in heat.  Water in the heat pump situation is considered degraded if not by contaminants at least as to temperature.

If you are adventurous you can clean the well yourself with a 3 or 4" light wall pipe with an elbow on top to direct the flow and a 3/4 to 1"air line going to within a foot of the bottom and a winch to raise and lower the pipe. The air line goes into a elbow welded onto the side of the larger pipe making an air lift pump that can be used as a sort of dredge to clean out the bottom.  If you have an interest in this let me know and I can get into more detail and specifics with you.  Be sure to check back with me for more details as it is possible to get hurt doing this-- just common stuff for well drillers though.

[JRR]

Glenn, thanks for info.  I value your insight.

My pipe-inside-a-pipe is nothing more than reconfigured "loop".   The concept would be: Filtered atmosphere would go "down" and atmosphere would return "up" ... hopefully with less water vapor and at a different temperature.

But your comment about the well water becoming contaminated with heat is interesting (disheartening, but interesting).  I was hopeful that even a single shallow well would act more as a "perfect" heat sink.

Not only is there no "free lunch",  ... there's no "reasonably priced lunch"!

[Daddymem]

Geothermal heat pump....that is one thing we looked at since we will already have a well.  It is a closed loop system so no pollutants get discharged back in to the groundwater but there would be a temperature difference.  I don't imagine it would make a difference given the amount of water below ground.  Here are some different configurations: http://www.fhp-mfg.com/geothermal/geothermal.htm

This can be used for heating and cooling.

[glenn kangiser]

I think the amount of heat being put into the well could affect the temperature of the well in varying amounts.  If the water underground is flowing -which is not real common then there may not be much change.  When a well is being pumped you create a cone of depression in which the bottom of the well becomes like a low pressure area and everything flows toward it.  Opposite that if you are putting heat into it the hottest point will be the well itself and the heat will have to dissipate in all directions.  Maybe it would go away fast enough- maybe not.  There are many variables.

Reading the above site it looks like they have taken this into consideration -maybe even have a track record.

[glenn kangiser]

Jonesy-- any progress report on the cool tube experiment

[jonsey/downunder]

Not yet mate, I have been a bit sidetracked over the last few weeks. We have had some decent rain here and the cockies have been breaking tractors flat out, so I have had to do some real work for a change. It's been a bit of a holdup on the building work. I have managed to get some of the deck on and will be updating the page in the next week or so.
jonesy  

[Okie_Bob]

Glenn, as I was reading thru Jonsay's posts I too was getting ready to jump him about the metrics when I got to your last one and you beat me to it!
Thank god, he had sent me his conversion program a few months back so I was one step ahead but still hated to pull it up to convert! How lazy can I get? Yeah, I know, pretty lazy!
Just have one question for Jonsay..how do you keep the guann's out of the buried pipe? I think you are talking about an open ended pipe that comes out of the ground at some point to take in hot air, pull it thru the tubes and discharge it into your house? Here in TX we have a LOT of snakes and you'd be amazed at the small holes they can get thru...how would you keep them out of the tubes and eventually your house?  I'm thinking some type screen but, not coming up with anything I'd feel really save with. Also wonder how you drain the condensation out the inlet if you have like a 90 degree ell coming out of the ground...am I missing something here?
Okie Bob in Texas

[jonsey/downunder]

Hi Bob,
Good to hear from you again mate. I have a blue heeler tied up at the entrance to the tubes and I reckon no goanna is going to mess with him. I think we should be safe enough there.
Na! That's a fib.  
There will be a mesh screen over the end of the tubes and they are sloped away from the house. I have a couple of holes drilled at the low point and have put a bed of sand around that area. Moisture shouldn't be too much of a problem as we have low humidity out here.
BTW I found a couple of mistakes with the conversion table I sent you; there is a better version on the index page of my website if you want to update.
jonesy

[John Raabe]

I don't have much experience with cooling tubes as I'm living in an area where there are only a handful of days a year when the thermometer reaches past 90ºF and then the night usually dips down into the high 60º's.

There might be two nights a year when we don't sleep with a blanket!

At any rate, here is a link for a somewhat elaborate passive air cooling tower.

http://millennium-ark.net/News_Files/INFO_Files/How.To.Stay.Cool.in.Desert.html

Simplified versions of this have been used in the Middle East for centuries. Usually there is some type of wind scoop on the roof pulling hot air out on the leeward side of any breezes (some modern metal ones can rotate while older units are fixed masonry). Then, below at a window on the shady side of the house, incoming air is run through a screen or cloth that is moistened by dripping water.

This is similar to some I saw in Iran and the kids usually had the job of keeping the water reservoirs filled.

These can work quite well in climates where the air has low humidity.

[glenn kangiser]

I was just thinking of adding one of these to my cabin yesterday- I'm at a point where it would be easy to incorporate into the front corner and let it exhaust out the greenhouse above (for a solar chimney).

[Amanda_931]

I want something that works in high humidity, sometimes a lot of hot weather, and maybe not much in the way of breeze.

(I'm afraid it's called a noisy AC unit I've already started this morning (it's for the dogs, of course!)

I do know of someone in West Virginia who has PAHS--the passive annual heat storage.   The person who sent me the air-to-air heat  exchanger plans (that I could forward).  Haven't heard from him in a while, but I recall that he thought it worked pretty well.

[John Raabe]

Yes, AC is the answer to high humidity cooling.  :'(

Refrigeration has made a huge difference in where people can live and where they choose to move to over the last 75 years. (Think dusty Phoenix in 1910).

Seasonal heat storage is doable but very expensive. I have never seen a system that even came close to having a realistic payback. Some of it is just hard work, so if you have a source of free labor (you?) then things like earth tempered air exchange systems can be effective. Especially in dryer climates like Jonesy's.

Some of these conduction systems seem to have problems with drop off efficiencies — that is they don't work as well the third year as they did the first. This may be due to seasonal heat retention in some types of soils.

The ones that really work are higher density water storage systems in insulated tanks. With enough money you could build a house that is 100% solar heated and cooled (run the pumps on PV).

You can also run your AC on solar panels for "free" too  , and maybe someday that will be cost effective.

[Okie_Bob]

John, I believe you are right on about A/C in humid climes such as E TX where I am building.  Glenn and Jonesy don't have the humidity problem Amanda and I have!
For me, I just had Icynene sprayed under my metal roof and inside all exterior walls. Then as soon as I got the sheetrock on the ceilings, I turned on my small window unit and viola! nice and cool. In fact, I turned on the window unit and left for the night, came back in the next morning and was surprised to find I could hang meat inside! Course I'm only talking 16X24 living area but, found I had to turn the A/C down to the point it barely uses the compressor and when it does, it produces enough water flood the yard and should provide enough for a garden! Course that was a day with 100 degree (F) and about 90% humidity.
I did insulate the entire under-roof area...about 50X24 and the cost was $2768. NOT a DIY project as you can't even buy the material unless you have a license with the manufacturer. Can't say enough about the benefits of this product and would be happy to expand on it if anyone is interested.
Okie Bob

[glenn kangiser]

How thick was your insulation and other relevant information, Bob.  No goanna problems I assume

Sounds great at any rate, Bob.  

[John Raabe]

A great example of the power of good insulation!

When you build a smaller house, and then insulate it well as you have, it really doesn't matter where you put in your heating or cooling - and it won't take much of either.

The better a house is insulated the less incentive you have to do some expensive alternative heating or cooling system.

You can hold your head high even if you are using electricity for both heating and cooling as you will only be sipping the juice lightly.

One mistake I see sometimes is that someone will build a small well insulated house and then spend $10,000 on a super efficient radiant, geothermal or other alternative heating or cooling system.

Such a place can likely be heated with two electric baseboards and cooled with a $100 window air conditioner. And, because good insulation (and good windows and doors) give you a uniform heat loss barrier, the temps will be about the same everywhere in the house no matter where the source is located.

Expensive, high-efficiency heating and cooling systems usually only make economic and comfort sense in INEFFICIENT or VERY LARGE houses.

[Amanda_931]

What John says is absolutely right.  And it kind of works in reverse as well.  A small amount of heat or coolth can make up for terribly inefficient structure as well.  Like my 2" of fiberglass, a lot of single-pane, mostly louvered windows.

I expect that I will go ahead and insulate well, even the main room of the guest cottage.  Although it may mean that I will sleep out on the screen porch most of the year.

Friend of mine thinks that icynene is wonderful.  I refuse to have it around until I get positive assurance that there are no isocyanates in it--"poly-" or otherwise.  

It's probably fine for most people who haven't worked with automotive paint, not even everyone who did back in when the formulations had a lot of it ended up sensitive to it, not even sure that I was, although the doctor at the time thought it fairly likely.  Once applied--they occur in the blowing agents for icynene--they disspate rapidly.  Once the stuff has dried, no problems even with someone deathly sensitive to it.

But I did make a heck of a lot of trips to emergency rooms and doctor's offices when I worked where the non--painters got worse doses of paint fumes than the painters (the rules were such that only the paint booths were subject to remediation and prevention).

[glenn kangiser]

I think you lost me, Amanda--   With a small amount of heating or cooling in an inefficient structure, won't you still be excessively hot or cold

[DavidLeBlanc]

A related question about super insulated spaces: what about air exchange? If air can't infiltrate/exfiltrate, sooner or later the air is going to go stale and there will be humidity build up from occupants and their activities. As an asthmatic, this concerns me greatly.

[glenn kangiser]

I think when you have successfully stopped nearly all sources of air movement you open windows and doors for fresh air- especially when you hear someone say, "Who stepped on the duck?"   :-/

[John Raabe]

Yes, good levels of insulation will likely mean some kind of controlled ventilation. In mild weather it can mean cracking a low and high window...

In very cold or very hot climates air sealing (http://www.mme.state.va.us/de/energybook/hbchap2.html) and air to air heat exchangers (http://www.warmair.com/html/air_to_air_exchangers.htm) can be worth the investment. For folks with allergies controlled ventilation can also mean filtered, and UV sterilized air if needed. (http://www.lightyears2.com/FreshAirPump.html)

The alternative is, of course, uncontrolled ventilation —which can have a whole host of other problems in severe climates.

In mild climates, who cares?... Just throw another shrimp on the Barbee.  

I guess the lesson here is that you have to be more anal-retentive in a severe climate. Maybe that explains the Scandinavians!  

[glenn kangiser]

Maybe thats what my uncle on my moms side was talking about-- the family came from Sweden and settled in Wisconsin.  He said Wisconsin winters were so cold you had to wet the bed just to stay warm..... but that was in the old days before the had fiberglass insulation etc.

[Okie_Bob]

Great followup posts everyone!!! And Glenn, I believe Jonsey has the goanna situation under control, at least for his 'cooling tubes'. Still not sure about the potential moisture problem he may have?

Glenn, I had 4" of Icynene blown under the metal roof and filled the 2X4 stud walls with the stuff. Not only is it great for temp but, also for noise control. I have an air compressor in the garage, right on the outside of the inner dividing wall and can't hear it running with the insulation. My wife is a bit unhappy as she loved the sound of the rain on the metal roof and now can't hear it at all!
One other point the contractor told me was that they recommend completely sealing off the attic area...no ventilation at all. I already had a power vent installed in the gable end and vented Hardi Board soffets on all four sides. He wanted to insulate off the soffit vents and close off the power vent fan and build the dividing wall between the garage and apartment all the way to the metal roof and insulate it...completely closing off the attic.
He had pictures with electronic thermometers reading the temp above and below the ceilings with 1/10th degree difference!!! In my current home I'm guessing the temp difference between the living area and attic something on the order of 40 degrees F (again for Jonsey). I thought that was pretty remarkable.
The place has been closed off all week as I have been in town working. Can't wait to see what the room temp is like when I get back down to the lake this evening!
Okie Bob

[John Raabe]

Let us know how this works out. There are some good arguements to be made for the elimination of attic ventilation and cathedral ceiling ventilation when air sealing can be counted on to block the delivery of moisture to the framing. Icynene can do this.

Most code inspectors have to be convinced however, and some parts of the country could be more problematic than others.

[jonsey/downunder]

I thought I might share this with you all. At this stage my tubes are still not hooked up or operating. I am hoping to get onto them in the next couple of weeks so it shouldn't be long until I can give a report of my own. The second e-mail was interesting in that I hadn't realised we could be eligible for carbon credits.


-------- Original Message --------
Subject:     Cool tubes
Date:     Mon, 27 Feb 2006 14:40:23 +1100
From:  Jim Mcknight <e-mail addy removed for privacy>
To:    <jonsey@unowhere.com.au>


Hi, thanks for your very interesting page. I've been following it with interest and was very taken with your discussion of earth tubes.

By way of reassurance, cool tubes do work, amazingly well. I owner built a 700 m2 house near Sydney with six 250mm cool tubes. With the help of the University of Athens SUMMER programme I modelled my site and calculated that I would get 82% of my cooling in lines only 30 metres long.  I buried them in a radial spread 3.5 metres deep in clay which has a year round 18.2C subsoil temperature. I have abundant cooling, virtually no refractory period and can keep the house at any temperature from 24C upwards effortlessly all year round. We completely aircondition our huge house for an overall cost of $15.60 a year the cost of running six blowers.

A problem though is that cool tubes are wonderful dehumidifiers and that with high dehumidification come all sorts of moulds etc. To combat this I use slow release chlorine tablets which knock this stone dead. When working gives a very faint ozone smell in the house which is quite pleasant.  A handful once a season does the job.

Thanks once again for your excellent journal.

Jim



Subject:
RE: Cool tubes
From:
"Jim Mcknight" <e-mail addy removed for privacy>
Date:
Wed, 1 Mar 2006 10:18:18 +1100
To:
"laurence/jones" <jonsey@unowhere.com.au>


Hi Jonsey, make sure you claim greenhouse carbon credits for your
system. This will return you a healthy dividend when you sell them to
Rheem or the other water heater mobs.
In haste, Jim

[glenn kangiser]

Great to hear from someone who is actually using it and it is working.  That is a monster house-- rough guess in my head conversion - I would say over 7000 square feet.

Thinkng about this a bit -putting the cool tubes up a hill sloping toward the house would assist the fans as cool air is heavier than warm air -the falling would pull more warm air down with it like a cooling tower.  Moisture would drain toward the bottom so a drain could take away the water to a collection tank or irrigate a garden.

Won't help much if your land is flat as a pancake, eh, Jonesy-- but then again you could construct your own small mountain with enough room and machinery.