[rockdoc123]

this all seems very climate dependant too me. I live in a place that has cold winters and hot summers. You can't have a house that "breathes" naturally to cool it in the summer as it is impossible to insulate it in the winter. What you can do which is cheaper and more energy efficient than AC is install an electric exhaust fan in your attic or invest in a window reverse circulation fan. I used both in the house we previously lived in and they worked quite well. The attic circulation fan you might turn on for an hour or so just as the sun goes down and it basically evacuates all of the heat that builds up and rises in the house. If you need a quick fix nothing beats one of these reverse circulation fans. Basically you fit the fan into a window where it is perfectly sealed (they come with a expandable frame that fits most window spaces, open a door to let in the cooler air and turn on the fan. It take about a half hour to an hour to fully change out the air in a fairly large home as I remember.
Alternatively if you live in a hot/humid country I think learning from the Spanish settlers is key. They built large haciendas that took advantage of breathable walls (adobe) and natural flow through circulation with large shaded courtyards etc. I've sat in several such courtyards and homes in Mexico and Colombia in 90+ temperatures and it has been quite pleasant.

[skyemoor]

$this->bbcode_second_pass_quote('rockdoc123', 't')his all seems very climate dependant too me. I live in a place that has cold winters and hot summers. You can't have a house that "breathes" naturally to cool it in the summer as it is impossible to insulate it in the winter.

[Ayoob]

Materials:

1. 5 gallon bucket full of ice and water
2. Aquarium pump, stuck to the bottom of the bucket
3. Plastic tubing from aquarium pump to copper tube coil
4. Copper tube coil zip tied to the back of a box fan
5. Larger plastic bucket to catch condensation from the apparatus

Method:

1. Stick aquarium pump to the bottom of the bucket with suction cups
2. Attach plastic tubing to aquarium pump
3. Attach copper tubing to the back of the box fan
4. Attach plastic tubing to copper tubing
5. Plug in aquarium pump and make sure cold water runs through the copper tubing
6. Turn fan on low
7. Enjoy nice cool breeze in the room

I keep about five 2-liters 90% full in the freezer for this situation. I'll fill the bucket with ice and water, and two hours later the ice is all melted and the water's warming up.

Before the last of the ice melts, I slip 1-2 frozen 2 liters in the bucket and let that suck the heat out of the water.

A frozen 2-liter will cool the room off for about half an hour or so. It takes a while for the 2-liters to freeze, so I keep a couple bags of ice handy too. As the day rolls on I probably dump another five or six bags of ice and cycle through all the 2-liters twice.

All told it probably knocks back the heat in my bedroom by about 15 degrees all day. The 105 degree heat becomes 90, which is a fucking godsend.

I only get the heat for 2-3 weeks out of the year and every year I think about blowing $800 on a window AC unit and I just can't pull the trigger on it. Not for 2-3 weeks.

Well, it's kind of like that. I don't cool off the whole house, just one room. I sure wouldn't do the living room/kitchen.. that would be crazy. I cooked breakfast in there, the dishwasher is running, the fridge is in there, etc.

But the bedroom, that I can keep separate.

Also, the fan doesn't blow through water, it blows through the copper tubing.

http://www.instructables.com/files/deri ... MEDIUM.jpg

Kind of like that, but I used a plastic bucket instead of a styrofoam cooler, and my copper tubing is in a relatively tight coil on the back of the fan instead of the rorschach test pattern that guy has.

-----------------------------------------------------------

This is copy/pasted from a thread on another board. Use at your own discretion.

[Novus]

Sounds terribly inefficient and a lot of work. Save yourself the hassle and buy this micro air conditioner for your bedroom. Costs about $140 with taxes and shipping.

Frigidaire

[Tanada]

Instead of all the messing about with a copper tube why not stop by a junk yard and pick up an AC condensor coil from a junk car? They cant be that expensive and they are already designed to transfer heat from fluid to air.

[3aidlillahi]

You're making your own AC so you have enough money for a 50" plasma? How did we ever get in this PO predicament, again?

[Keith_McClary]

$this->bbcode_second_pass_quote('3aidlillahi', 'Y')ou're making your own AC so you have enough money for a 50" plasma? How did we ever get in this PO predicament, again?

[perdition79]

Cool, brings back old memories.

We made things like this homemade a/c when I was in middle school; it was good enough for third place in the science fair. Granted, we used 3 gallons of a 40% rubbing alcohol solution for the fan, ammonium nitrate fertilizer solution chilled with bags of ice and road salt for the heat sink, and copper tubing all around -- ammonium nitrate won't remove heat from water when plastic tubing is used.

That was fifteen years ago. Imagine trying to buy the supplies now! Guys with black suits would be knocking at my door in a matter of minutes, if I even made it out of the feed store!

[alpha480v]

I think I could find a $100 for a cheap window unit instead of going through all that trouble.

[kpeavey]

Gotta think bigger:
try a big tank outside stored in the shade on the north side of the house.
Add a pump in the 30 watt range, plumbed to a radiator/fan combo inside the house, a second radiator outside in the shade on the north side of the house, finally returning to the tank

some math:
150 gallons/hour @ 8#/gallon=1200 pounds/hour, can be increased with more flow/bigger pump.
20 degree temperature change, drawn from the inside air, =24k BTU/hour cooling ability

There are many different ways to configure such a jerry rigged contraption.
-more radiator
-more fan
-more flow
-The earth can be used as the thermal dump instead of the outdoor radiator. Burying some sort of heat exchanger underground at 4-6 feet will offer temperature stability much cooler than the outdoor temperature in the shade.
-The indoor radiator/fan can be part of a central air conditioning system.
-Add a solar thermal hot water system on the roof, get free hot water while removing incoming energy from the house

The only requirement for such a system to work is water at a lower temperature than indoors. The cooler it is (or the greater the difference), the better it will work.

some more math

window AC pulling 1500 watts/hour for 10 hours =15 kWH/day @ 12 cents/kWH=$1.80/day

30 watt water pump
100 watt fan
130 watts/hour for 10 hours=1.3 kWH/day @12 cents/kWH=$0.16/day

I use a similarly designed system to heat the greenhouse, costs me 15 cents/month to operate

[alpha480v]

What's the Cost of the tank, piping labor to dig and install. How much is your time worth? Is all that really cheaper than running a window unit?

[Madpaddy]

Ayoob,

Have you considered a cooling vest. We use similar products for certain jobs in the army and they work well.

http://www.climatechsafety.com/LiteAir.aspx



You can be cool anywhere and this model costs $129.

[pedalling_faster]

i use the wet T-shirt technique, when it gets to 85+.

just dunk a T-shirt in the sink, wring it out, put it on.

when it gets into the '90's - i just take a shower once an hour.

when it gets into the 100's - i lay in the bathtub thinking about Peak Oil.

[Ayoob]

$this->bbcode_second_pass_quote('kpeavey', 'G')otta think bigger:
try a big tank outside stored in the shade on the north side of the house.
Add a pump in the 30 watt range, plumbed to a radiator/fan combo inside the house, a second radiator outside in the shade on the north side of the house, finally returning to the tank

some math:
150 gallons/hour @ 8#/gallon=1200 pounds/hour, can be increased with more flow/bigger pump.
20 degree temperature change, drawn from the inside air, =24k BTU/hour cooling ability

There are many different ways to configure such a jerry rigged contraption.
-more radiator
-more fan
-more flow
-The earth can be used as the thermal dump instead of the outdoor radiator. Burying some sort of heat exchanger underground at 4-6 feet will offer temperature stability much cooler than the outdoor temperature in the shade.
-The indoor radiator/fan can be part of a central air conditioning system.
-Add a solar thermal hot water system on the roof, get free hot water while removing incoming energy from the house

The only requirement for such a system to work is water at a lower temperature than indoors. The cooler it is (or the greater the difference), the better it will work.

some more math

window AC pulling 1500 watts/hour for 10 hours =15 kWH/day @ 12 cents/kWH=$1.80/day

30 watt water pump
100 watt fan
130 watts/hour for 10 hours=1.3 kWH/day @12 cents/kWH=$0.16/day

I use a similarly designed system to heat the greenhouse, costs me 15 cents/month to operate

[kpeavey]

$this->bbcode_second_pass_quote('alpha480v', 'W')hat's the Cost of the tank, piping labor to dig and install. How much is your time worth? Is all that really cheaper than running a window unit?

[Ayoob]

It's not so much about the setup cost or the time, it's about heating or cooling your house independently. If I was so inclined, I would pick up a radiator and use that, but I already had the copper tubing so I just went with that.

I remember calling the power company and asking how much it cost for me to run my box fan one time. I'd turned it on in early June and it was late August. The customer service rep said it was probably about a nickel an hour. The fan was $20, so I figured a nickel an hour is 24 nickels a day... about a buck a day... June, July and August added up to about 90 bucks.

Wow.

So running the fan cost me four and a half times the cost of the fan itself?

I could have picked up a timer and shut the fan off at 9AM (time to go to work) and have it fire up again about 4PM to cool the place off when I got home, and I could have skipped the most expensive part of the juice, AND not even noticed it was ever off. My power bill probably would have dropped by 50-60 percent.

Running a heat exchange system cuts my power bill by 70% or so for heating and cooling, which is a huge savings for me. Now if I can figure out how to use passive solar to heat my bathwater, cooking, dishwashing, etc... I'm in the pink!

All of a sudden, my long-term vision of living an energy-extravagant lifestyle with minimal energy inputs can become a reality. I just have to piece it together one bit at a time.

[smallpoxgirl]

$this->bbcode_second_pass_quote('Ayoob', 'R')unning a heat exchange system cuts my power bill by 70% or so for heating and cooling

[kpeavey]

$this->bbcode_second_pass_quote('spg', 'Y')ou are aware how much heat a 50 inch plasma TV puts out right?

[Keith_McClary]

$this->bbcode_second_pass_quote('Madpaddy', 'A')yoob,

Have you considered a cooling vest. We use similar products for certain jobs in the army and they work well.

http://www.climatechsafety.com/LiteAir.aspx



You can be cool anywhere and this model costs $129.

[aflatoxin]

There are several facilities in Albuquerque that have big (10,000+ gallon) reservoirs that are turned into ice over the course of winter. I'm not sure if they are filled with water of some kind of salt. They are very cold at the end of the winter, as the heat pumps have pulled all of the usable energy out of the fluid.

Then, all summer long, the excess heat in the buildings is put into the tanks, heating the fluid and cooling the building. At the beginning of winter, the heated fluid from the summer is cooled again and the energy is used in the buildings.

I'm told that these setups can cut 25% of annual energy use needed to heat and cool the facilities.