EcoRenovator  

Go Back   EcoRenovator > Improvements > Other Improvements
Advanced Search
 


Blog 60+ Home Energy Saving Tips Recent Posts Search Today's Posts Mark Forums Read


Reply
 
Thread Tools Display Modes
Old 06-12-15, 02:42 AM   #1
Acuario
Apprentice EcoRenovator
 
Join Date: May 2011
Location: Tortosa, Spain
Posts: 204
Thanks: 2
Thanked 61 Times in 38 Posts
Default Cheap efficient overnight cooling

I'm sure this has been done before but maybe will inspire others..

Our summer days can get very hot in Spain but the nights are much cooler. Leaving the Windows open to let cool air in works to a degree but there seems to be little air movement at night so the cooling isn't great.

I'm not a fan of air conditioning so although we have it in the bedroom I've rarely used it and the few times I have it has just been to cool the bedroom before going to bed, I've not left the machine running overnight.

So to capitalise on the lovely cool air I decided to build a window fan system using cheap table top fans. I found some 30cm fans that were very cheap on ebay and then simply cut a piece of foam board to the size of the open window and mounted 4 fans in it. The fans are mounted so they blow from inside to outside, pulling cool air in through any open window. As we have window blinds I can just lower the blind if I don't need to use the fans.

It works extremely well, can be easily regulated (plug in as many fans as I need), and does a great job of pulling in cool air.

Acuario




Attached Thumbnails
Click image for larger version

Name:	20150612_082244a.jpg
Views:	891
Size:	53.8 KB
ID:	5443   Click image for larger version

Name:	20150612_082310a.jpg
Views:	3212
Size:	63.5 KB
ID:	5444  

Last edited by Daox; 06-12-15 at 10:34 AM..
Acuario is offline   Reply With Quote
The Following 2 Users Say Thank You to Acuario For This Useful Post:
AC_Hacker (06-16-15), Daox (06-12-15)
Old 06-12-15, 10:43 AM   #2
Daox
Administrator
 
Daox's Avatar
 
Join Date: Aug 2008
Location: Germantown, WI
Posts: 5,452
Thanks: 1,102
Thanked 362 Times in 294 Posts
Default

Very nice setup!

I do a similar thing where I use a box fan in my upstairs windows. I usually stuff a pillow next to it to get it to seal up better. I like your solution better though.
__________________
Current project -
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.



To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
&
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Daox is offline   Reply With Quote
Old 06-15-15, 05:07 PM   #3
Drake
DIY Guy
 
Join Date: Jan 2011
Location: Mpls,MN
Posts: 315
Thanks: 2
Thanked 17 Times in 17 Posts
Default

A very strict cycle of heavy night time venting with whole house fan and closing up during he day last summer in my very air tight well insulated cabin kept temps well cooler than outside(as comfortable as AC) all day but lead to some heavy mildewing of leather items and some fabrics in storage areas where humidity condensed and air flow was stagnated. So natural night cooling can be overdone. Could use dehumidifier but that is a power demand I would not like to add. May have had more humid period last summer then normal. But I think that I was night cooling to near dew point inside during the day to much.
Drake is offline   Reply With Quote
Old 06-16-15, 09:53 AM   #4
AC_Hacker
Supreme EcoRenovator
 
AC_Hacker's Avatar
 
Join Date: Mar 2009
Location: Portland, OR
Posts: 4,002
Thanks: 303
Thanked 705 Times in 527 Posts
Default

Quote:
Originally Posted by Acuario View Post
...I'm not a fan of air conditioning so although we have it in the bedroom I've rarely used it and the few times I have it has just been to cool the bedroom before going to bed, I've not left the machine running overnight...
I really like this, too. Very elegant solution to a problem that many people are faced with.

I've thought to see if there could be improvement to an already good solution... only things I could come up with would be:

1. Use computer fans for greater energy efficiency

2. Use an acoustically 'dead' mounting board like Medium Density Fiberboard

3. If you really wanted to go over the top, you could hack a temperature controlled PWM speed controller.

Good work Acuario!

By the way, were you ever able to make significant progress on the Inverter Mini-Split compressor controller? Your work went farther than any I know of.

Best,

-AC_Hacker
__________________
I'm not an HVAC technician. In fact, I'm barely even a hacker...
AC_Hacker is offline   Reply With Quote
Old 06-16-15, 10:31 AM   #5
Daox
Administrator
 
Daox's Avatar
 
Join Date: Aug 2008
Location: Germantown, WI
Posts: 5,452
Thanks: 1,102
Thanked 362 Times in 294 Posts
Default

I think building humidity control into the fan controller would be a great idea. I love the idea of cooling the house off with fans, but like Drake, it can get REALLY humid here. I think some sort of dew point calculating controller would be really awesome.
__________________
Current project -
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.



To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
&
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Daox is offline   Reply With Quote
Old 06-16-15, 01:22 PM   #6
Acuario
Apprentice EcoRenovator
 
Join Date: May 2011
Location: Tortosa, Spain
Posts: 204
Thanks: 2
Thanked 61 Times in 38 Posts
Default

Originally, would you believe 10 years ago, when I knew I was moving to Spain I bought a whole load of computer psu cooling fans and made up a 6x6 grid of them to achieve roughly what I have now.

It did work but it was incredibly noisy and needed a separate psu to run the fans + wiring and mounting them wasn't easy as there was little space on them for mounting. I eventually abandoned them but the idea has always been there.

The fans now are mounted on a high density foam panel, the type they use for double glazing and the noise when all four fans are running isn't anywhere close to the old psu fans. The fans also have 3 speed settings so could be varied if necessary but for the moment I'm running them at full speed.

I did think about adding a controller to switch the fans on/off etc. but I wanted to keep it as simple as possible and quite honestly I think it would be somewhat overkill to add much control. Possibly adding a simple 24hr timer to switch them on/off is the most that is needed.

AC - sadly not yet - lack of time! Between the beginning of November and middle of February we demolished the old part of our house and built a new 140m2 (1500 sq ft for the imperial guys!) house for my parents. It is mega insulated (sprayed on expanding polyurethane foam 5cm in all the cavities, 7cm in the roof, 5cm in the floors, solar reflective glass in all the double glazed windows) and has under floor heating/cooling (using a home made air/water heat pump) which works impressively well. - Maybe I should start a thread as it is an on-going project with RS485 wall thermostats feeding back to a central controller to open/close the under floor heating valves, mixed heat pump/solar panel/ last resort oil boiler for heating..the list goes on.

I also invested time (as a necessity) into obtaining my certification for handling refrigerant gasses (it is a European requirement). Without this certificate I could no longer buy refrigerant gasses.

I still have the machine in my workshop and will get back to it at some point.
Acuario is offline   Reply With Quote
Old 06-16-15, 01:26 PM   #7
Daox
Administrator
 
Daox's Avatar
 
Join Date: Aug 2008
Location: Germantown, WI
Posts: 5,452
Thanks: 1,102
Thanked 362 Times in 294 Posts
Default

We'd love to hear about your parent's house build! Sounds great.
__________________
Current project -
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.



To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
&
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Daox is offline   Reply With Quote
Old 06-16-15, 02:48 PM   #8
AC_Hacker
Supreme EcoRenovator
 
AC_Hacker's Avatar
 
Join Date: Mar 2009
Location: Portland, OR
Posts: 4,002
Thanks: 303
Thanked 705 Times in 527 Posts
Default

Quote:
Originally Posted by Acuario View Post
Between the beginning of November and middle of February we demolished the old part of our house and built a new 140m2 (1500 sq ft for the imperial guys!) house for my parents. It is mega insulated (sprayed on expanding polyurethane foam 5cm in all the cavities, 7cm in the roof, 5cm in the floors, solar reflective glass in all the double glazed windows) and has under floor heating/cooling (using a home made air/water heat pump) which works impressively well. - Maybe I should start a thread as it is an on-going project with RS485 wall thermostats feeding back to a central controller to open/close the under floor heating valves, mixed heat pump/solar panel/ last resort oil boiler for heating..the list goes on.
Absolutely!!

Bring it on.

-AC
__________________
I'm not an HVAC technician. In fact, I'm barely even a hacker...
AC_Hacker is offline   Reply With Quote
Old 06-18-15, 09:41 AM   #9
MN Renovator
Less usage=Cheaper bills
 
MN Renovator's Avatar
 
Join Date: Nov 2010
Location: Minneapolis, MN
Posts: 930
Thanks: 41
Thanked 113 Times in 87 Posts
Default

Quote:
Originally Posted by Drake View Post
A very strict cycle of heavy night time venting with whole house fan and closing up during he day last summer in my very air tight well insulated cabin kept temps well cooler than outside(as comfortable as AC) all day but lead to some heavy mildewing of leather items and some fabrics in storage areas where humidity condensed and air flow was stagnated. So natural night cooling can be overdone. Could use dehumidifier but that is a power demand I would not like to add. May have had more humid period last summer then normal. But I think that I was night cooling to near dew point inside during the day to much.
I use the air conditioning if the dew point will be above 55 degrees F otherwise areas this would be an issue for me. Luckily we've had enough nights with dew points under 55 degrees F to where I've only had the house above 76 degrees in the hottest parts three days total so far. We've been lucky with a few 50-55 degree lows at night with dew points under 50 to where this has worked well. Usually this time of year that is out of the question. I find using the dew point forecast that comes with the weather.gov hourly charts to be especially useful and surprisingly accurate for temperature and dew point estimations. Oddly enough they seem to be the most accurate source of rain/snow forecasts that I've been able to find too, granted it isn't perfect because no weather forecast will be but it seems as close as it gets. It seems we are on our final week or two until cooling with windows open is not possible without high dew points and I will resort to air conditioning. ..haven't used it yet though which is the first year since I moved into this place 5 years ago in 2010 where I've been able to stretch it to mid-June without AC to keep the house low in moisture and cool here in Minnesota. It's been a great summer so far, mostly because of the rain keeping the clouds overhead. Not the best for the solar system though, I'm probably 100kwh short for the past 30 days and about the same for the 30 days before that.
MN Renovator is offline   Reply With Quote
Old 06-19-15, 01:19 PM   #10
Drake
DIY Guy
 
Join Date: Jan 2011
Location: Mpls,MN
Posts: 315
Thanks: 2
Thanked 17 Times in 17 Posts
Default

My whole house(cabin) cooling fan is temp controlled(which I overrode last summer to see how cool I could get it). I will use it this summer and try to better match avg dew points. Iwas getting indoor morning temps into the 50's before closing up for the day. Cabin is very tight and insulated/shaded so interior temp stayed very cool well into late day. Which was very welcome as I was working hard outside during the heat of the day underpinning new foundation for new addition. I was pushing the cool beyond normal comfort.

Drake is offline   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 07:55 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.
Ad Management by RedTyger
Inactive Reminders By Icora Web Design