Solar powered AC air conditioning, a bummer or a challenge?

[billvon]

What about passive cooling? You don't to go down very far before the ground temp drops down to around 50 degrees. Did a trench, lay tubing and pump water through it to a exchanger in the shack with a fan behind it. 50 degrees isn't exactly cold but it is cool enough that it would keep the temperature in the room down.

Earth tubes can work well in good environments (i.e. cold earth) but don't work well in southern climates where the ground is warmer year-round. As with any cooling system you have to be careful with condensate management; if the water is allowed to sit in the tube you get mold and other problems. They also take up a lot of space. You need hundreds of feet of tubing to get good coupling to the earth.

But if you can manage all that you can get very cheap cooling, at least on days that aren't _too_ hot.

[russ]

What about passive cooling? You don't to go down very far before the ground temp drops down to around 50 degrees. Did a trench, lay tubing and pump water through it to a exchanger in the shack with a fan behind it. 50 degrees isn't exactly cold but it is cool enough that it would keep the temperature in the room down.

Sorry Jim but that is a green myth - to get the heat transfer it would take a very long tunnel plus the 50° is an old wives tale. You also end up with a real potential for a mould problem - nasty!

[jimindenver]

What about passive cooling? You don't to go down very far before the ground temp drops down to around 50 degrees. Did a trench, lay tubing and pump water through it to a exchanger in the shack with a fan behind it. 50 degrees isn't exactly cold but it is cool enough that it would keep the temperature in the room down.

[SunEagle]

No room for misguided enthusiasm on this forum.

I wonder if a truck/van air conditioner could be a solution for small rooms. There wouldn't be any inverter efficiency loss in that scenario. Nor would there be the inflated cost of a home DC air conditioner....
Thoughts anyone???

Nice idea but most vehicle air conditioners use the engine to run the compressor not the battery or alternator.

My RV has two roof top units but they will only work when I have the generator running or I am plugged into a grid connection. They are just too big to run off the coach batteries.

[PhillyTitan]

What you think he claims is completely false, and was the point of my intervention. A window shaker is 4 times more efficient than any Peltier unit.

No room for misguided enthusiasm on this forum.

I wonder if a truck/van air conditioner could be a solution for small rooms. There wouldn't be any inverter efficiency loss in that scenario. Nor would there be the inflated cost of a home DC air conditioner....
Thoughts anyone???

[Sunking]

Alan, my point was that the air conditioner you built had a power consumed to btu ratio that was 3-4 times higher than a window unit. I don't see how you can run that entire ship with so little cooling power.

What you think he claims is completely false, and was the point of my intervention. A window shaker is 4 times more efficient than any Peltier unit.

[PhillyTitan]

Hello,

Evaporative cooling (swamp coolers) only work is dry climates... I am basing this in climates with 70% to 80% humidity.

Alan

Alan, my point was that the air conditioner you built had a power consumed to btu ratio that was 3-4 times higher than a window unit. I don't see how you can run that entire ship with so little cooling power.

[Mike90250]

The big problem with the peltier module, is only a 40F difference from the hot to the cold side. Second, is the waste heat that has to be discharged from the hot side. About 70% of the power consumed is simply converted into heat, and only a small amount of heat can be pumped from the cold side.

Then you also have to discharge the condensate water that will collect on the cold side.

[russ]

Ahh. I understand now. My Daughter in law has a fan where you can connect a water hose creating a fine mist which is then blown out. Worked real good during their 4th of July picnic.

In Vegas street cafes use them - an umbrella of the fine mist.

Here they do help

On an industrial basis the dry fog is used for dust suppression in material handling systems. The water droplets are fine enough that you can run your hand through the mist and it comes out dry - hene "dry fog".

It is a high pressure system with special nozzles but nothing exotic.

[SunEagle]

Fresh Fog Fresh Fog Cooling Mist System | 80042-MISTER

http://www.sears.com/fresh-fog-80042...-SPM7555082402

Works best in dry climates but even here with 75% or more humidity it cools well.

Ahh. I understand now. My Daughter in law has a fan where you can connect a water hose creating a fine mist which is then blown out. Worked real good during their 4th of July picnic.

[russ]

dry fog!!!!

Fresh Fog Fresh Fog Cooling Mist System | 80042-MISTER

http://www.sears.com/fresh-fog-80042...-SPM7555082402

Works best in dry climates but even here with 75% or more humidity it cools well.

[SunEagle]

evaporative cooling also includes dry fog.

dry fog!!!!

[russ]

Evaporative cooling also includes dry fog.

[Hkalan]

Hello,

My most sincere apologies !

Evaporative cooling and compressed gas cooling have always been defined as different methods to me.

Sorry to trouble you !

Alan

[Sunking]

[QUOTE=Hkalan;116060]

Evaporative cooling (swamp coolers) only work is dry climates... /QUOTE]Evaporative cooling also means vapor compression of a gas like Freon

Hello!