Self Sustainability and Energy Saving

I've read dry ice should not be used. There is actually tons of info out there on these as well as a videos folks made showing step by step. Lots of folks using DC fans from batteries and solar panels. Pretty neat actually.

My wife is under the weather so I was aiming to make dinner, really wanted to try a larger fan so I decided to just heat some leftovers up in the microwave. Then went out to get another exhaust style fan.

The first fan was 4", 11 watt; the smallest I could find in a search of a few places tonight was an 8", 35 watt that I think may be too much. Ideally a 6" fan around 20-25 watts is what I think would work best. The airflow with the 8" fan is great but the air temp seems a bit lower, which makes me think a 6" fan would be better or maybe change to a 3" output to give more time on the ice. Since I've already cut out the top of the cooler and installed the 8" fan I will try 3" PVC fittings tomorrow to see how that works.

If anyone is thinking about making one, give me another day or 2 to work out the kinks so you aren't buying multiple coolers and fans. Ice costs 2 peso for one of the sticks, so if you could get by with 15-20 of those at night (when most of us need to be cool to sleep well) you are talking 30-40 peso a day. Obviously there is electric involved for the fan, or the initial investment on a solar panel and battery to use at night. Most folks that use them in the US from what I saw they were freezing a few 2 liter bottles each day to use so that could be cheaper than buying ice but you sacrifice freezer space unless you have a chest freezer or something extra.

Should be an energy savings when you look at the minimum cost to make one and how easy it is.

Shawn

 

Hey Shawn.
If you wan to control the speed of your 8" fan (or any fan) all you need to do is put a capacitor in series with the motor.
I took apart a three speed floor fan and the insides was just a couple of capacitors and the switches.
The caps were something like 1.0 uF and 0.47 uF or something like that. Checkout the guts of your floor fan.
There are a few places around town that can sell you some caps.
cheers
Dave

 

Dave, yep the fans are simple; this post was really about finding some ways to conserve energy while keeping cool.

I don't believe we have had the chance to meet yet, always up to meet folks and a good discussion always works out well.

Shawn

 

I changed the 2" PVC to a 3" PVC outlet and it is pushing air out nicely. I went to Dumaguete today and picked up a 6" exhaust fan while there. I will get another Styrofoam cooler tomorrow and build another one using the 6", 23 watt fan with a 2" outlet so I can compare them.

I was thinking about getting a small cooler so I can use the 4" fan I first bought with a 1" outlet just to see how it would work.

Shawn

 

This has really been a fun experiment. I pulled out the infrared thermometer that I picked years ago when in Korea, new battery and checked the temp on the ice as a base to make sure it was still somewhat calibrated.

I closed up the bedroom earlier so it was d*mn hot with no air flow, around 86-89 and over 90 at the ceiling.

Looking at a 8" exhaust fan with a 3" PVC exhaust against a 6" fan with a 2" outlet. The temps I have read over the past few hours have been fairly consistent, the temps are lower with the 2" outlet but the air flow is a bit less than the other one.

I put 20 pieces of ice in each cooler at 5 PM and with the ambient temps they were putting out air around 74 degrees. To me that is a pretty decent for sleeping.

I'll let them both run through the night (with windows and doors closed) and see how the ice/water is in the morning. My initial thoughts are that they are great when blowing straight on you, I will sleep comfortably tonight, very cheap to build but doubt they could cool anything short of a very small room.

On a side note, the vulca seal product I use on the first one, don't remember the name off the top of my head. It was in a mostly black package with a diagonal cut; anyway it did not react too much with the Styrofoam. The last 2 I did I used the vulca seal and it melted the Styrofoam a bit, not a big deal as you can use a second coat for the exhaust. I used silicon caulk to secure the fan and that had no interaction, so it could be used as well for the exhaust pipe.

Shawn

 

The water in the cooler with the 8" fan and 3" outlet was basically luke warm at noon; the water with the 6" fan and 2" outlet was still ice cold at noon when I dumped out the water...ice cold water for the dogs and the luke warm water for my grape tomatoes.

There was quite a bit of condensation on the bottom of the coolers sitting on the floor last night. I put one up on some 2X2's (just to be sure they are not slowly leaking, which I doubt) I am also trying another little experiment to see if the air flow will cool a beer down faster than a warm beer in the fridge figuring the airflow may make a difference.

Shawn