Monday, August 6, 2018

Need shade from the sun to cut down on a/c use

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originally posted, 6.23.17, updated

8.6.18:

Why return to this post?  It seems that I may have found a solution to the puzzle of how to climate control a space with the least energy input.

Reading over this post reminds me that I could use the freezer to make ice that just about eliminates the need for an a/c.  The system that I have now allows me to reduce a/c use to a few minutes a day.

In order to get more margin for error, an a/c may still be desirable.  But for everyday use, an a/c can be eliminated.

One more thing I'd like to try is to make a roof that combines water distillation with cooling the roof.  There is no cover on the roof of the trailer now.  I am thinking a cover that also distills water would dissipate heat, and make it very comfortable in here even without an a/c.

I won't build a roof for the trailer, though.  I will consider one for out west, though.

6.30.17 , 7:30 :

This will be the final update to this post.  I have refined the system as well as I can.  Maybe it could be tweaked here and there for slight improvements.  But I have to think about expenses and such.  I spent about 400 bucks on these projects since I got back.  Well, I don't have that kind of money to spend on anything anymore.  It is mostly make-work-keep-busy type of stuff.

I did accomplish two straight days without using the a/c.  Do I really want to live this way, though?  Not unless I can increase the comfort level.  The a/c is awful tempting.  In fact, after two days without it, I turned it on this morning.

This morning?  Yeah.  For some reason, it doesn't cool all the way down to outside temperature in here.  It stays noticeably warmer, about five degrees.  I cannot explain it.  It is something like you might want to tweak for better performance, but how?  By spending more money?

I need to move on, and so I will.


6.28.17,  23:00 :  


Another experiment today. This one started at about 5 pm, and is continuing as of this writing. The melting ice did not really help much with the heat, as far as I can tell. It is still too hot in here. There needs to be shade.

The sun is too much, in other words.

The ice is nearly all melted, and it is feeling more comfortable now.  But it is only 80 degrees outside, so it should feel more comfortable.

6.27.17, 

20:30 :

I correct the previous statement that the ice lasted nine hours, it lasted seven hours.  The new ice has frozen in the freezer.  This means that it took about twelve hours for it to freeze:  since I replaced the ice taken out this morning with some water that will replace the melted ice in the Coleman on the next experiment.

The bottom line is that a daily swap out is feasible.  It will take less than a day to freeze each batch of water that has to be replaced.

14:30 :  

The ice has melted.  It lasted about nine hours in mild conditions.  The real test comes when it gets really hot again.

10:15 :

After three hours, about half the ice is melted.  Very nice in here.


7:00 :

A test of the "coffin concept" is underway.  It is utilizing about 50 lbs of ice obtained from the freezer, and the passive solar setup from last winter.

The results so far are interesting, to say the least.  It is noticeably cooler in here than in the rest of the trailer, but outside is supposedly cooler outdoors than in here.  For this to be so, an uncomfortable thought just occurred to me.  That is to say, I am heating the trailer with the freezer, and cooling it in here.  Just moving heat around, not out.

The freezer would have to be outside in any serious arrangement.

But it does feel really nice inside here.  I'd say about six degrees cooler than in the rest of the trailer.

A better time to test would be in the late afternoon.  Of course, I had to do it this way. /sarc


6.24.17 :

Boy, was the need for shade confirmed yesterday.  It was supposed to have reached 105 degrees Farenheit.  I fought  a losing battle against it.  Finally had to give up and turn on the a/c when it was 102 inside.  Nothing seemed to help until I called for the cavalry.  Lesson learned.



the original post follows:

This post will go into the Construction sub-series of the off-the-grid main series of posts.  These posts can be accessed from a table of contents and watched individually or in series from beginning to end.

The last time, I was working on the "coffin concept", which is to save on power and electricity through the use of only small areas to climate control.  Now that I have one, I have managed to do a few things that will give me an idea of what I need to do on this to make it work better.

At present, it is not working well.  The swamp cooler is not cooling that well.  The misting system is not helping either.  Even watering down the trailer doesn't help that much.  With everything I could think of being done, I still have to use the a/c for several hours a day.

The next idea is to freeze water with that big freezer I bought a couple years ago.  It will go into the passive heater system.  It will work the same way as the passive solar, because the water is in a closed system.  This system will not divert the water into an outside system, but will keep the water circulating through the heater core and back to the Coleman cooler.  The freezer will keep the water near freezing, and a box fan will circulate the air through the heater core.

My thinking is that to freeze 40 lbs of water won't use that much electricity.  It won't supply as much cooling power either, but it is only 64 square feet.  This matches well with my freezer experiment in 2014.    Only 290 watts per hour for that much area, if everything works out.  That would give about three or four hours of cooling.  Forty pounds would figure about at less than two hours actually.  I don't know how realistic this is yet.  Still experimenting.

Keeping in mind that the whole room doesn't need to be cooled down, just me in my little area.  If it starts at eight pm, by ten pm, it should be cooling down anyway.

Another thing to remember is that there is no shade in this location.  I can make more shade, so I have got that going for me.



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