Skylights....any that pass Visible without IR?

Straw bale, adobe - heck, even car tires can be used to construct a solid, earth friendly, energy efficient house! Share your alternative building experiences and ask for advice here

Skylights....any that pass Visible without IR?

Postby 470rigby » Thu Aug 05, 2010 10:28 am

I have been looking (unsuccessfully) for a solution to the low light problem we have on hot days when the blinds are down and the drapes are drawn.

Our practice is to run the interior lighting...no problem in hot days when the is a surplus of PV energy, but the "trouble & strife" has this thing about it being un-natural.

I have not been able to find Skylights that will pass light in the visible wavelenth range WITHOUT admitting infrared..which is not welcome in an un-airconditioned building on a hot day!

Anybody got any ideas on this?
470rigby
Solar Crusader
Solar Crusader
 
Posts: 129
Joined: Tue Oct 06, 2009 10:57 am

Re: Skylights....any that pass Visible without IR?

Postby australsolarier » Wed Jan 19, 2011 6:26 pm

hi
i put in a sky light in the toilet and measured the temperature with the infra red thermometer: about 2 - 4 degrees warmer on the light than the well insulated ceiling. just install so the sun's rays cannot shin down the tube directly but need to be reflected along the sides. i had the same worries with the heat gain before installation myself.
greetings urs
australsolarier
Solar Crusader
Solar Crusader
 
Posts: 321
Joined: Sun Mar 28, 2010 9:27 am

Re: Skylights....any that pass Visible without IR?

Postby thermalleak » Thu Mar 31, 2011 7:03 am

Hi guys my first post but glad to be here.
Due to an extension I built to my home a couple of years back we lost a lot of light to the rear of the property as the extension basically took away most of the afternoon sunshine. As a result we were left with quite dark areas in a couple of the rooms. A new window was not an alternative due to planning regulations so we fitted a couple of solar light tubes. There are quite a few on the market which and all come in a variety of cost and quality. The ones I fitted were quite expensive but I have to say they do a good job. Some days the rooms are so bright you would never know we ever had a problem with the loss of light previously. They have sort of a plastic dome out on the roof and a diffuser on the inner attached to the ceiling.
They were simple to fit and really didn't cause any mess or disruption the main problem was making the tiles around the roof section fit but they do have various different configurations depending upon you roof covering.
Overall I was a bit sceptical but actually would fit them again if I needed to without hesitation.
I am not sure if they can be fitted with IR filters but I am sure the manufacturers would be able to advise you of this.
Just do a web search for solar tubes or light tubes and you will find loads. Maybe this could help you keep light but not too hot :)
Check out my site at www.thermalleakdetector.org to see if any of my reviews might be able to save you a little bit of money. Every little helps as they say .....
thermalleak
Solar Supporter
Solar Supporter
 
Posts: 2
Joined: Thu Mar 31, 2011 6:44 am
Location: United Kingdom

Re: Skylights....any that pass Visible without IR?

Postby australsolarier » Thu Mar 31, 2011 11:00 am

i find the leaking of rain water in heavy rain is a bit of a problem. however different products might not leak.
australsolarier
Solar Crusader
Solar Crusader
 
Posts: 321
Joined: Sun Mar 28, 2010 9:27 am

Re: Skylights....any that pass Visible without IR?

Postby 470rigby » Thu Mar 31, 2011 11:31 am

thermalleak wrote:I am not sure if they can be fitted with IR filters but I am sure the manufacturers would be able to advise you of this.


Hi thermalleak,

Maybe be in the UK this could happen, but the Skylight installers down here in OZ are basically cowboys that can only manage blank looks (or that "what sort of a nitpicker are you" look!), when you ask about IR transmission.

Strange, when we live in a hot climate, but everyone here runs an AC, so there is no problem!

There are some window installers that use low-e (low emmission) glass, but they can't give any real data on the extent of reduced indoor temperatures.

The other problem I have is Cathedral ceilings which rules out the light tube type of product.
470rigby
Solar Crusader
Solar Crusader
 
Posts: 129
Joined: Tue Oct 06, 2009 10:57 am

Re: Skylights....any that pass Visible without IR?

Postby thermalleak » Thu Mar 31, 2011 10:47 pm

Hi Rigby I understand what you are saying about skylight fitters attitudes - don't worry its not just down in Oz where they have them, we have more than our fair share of blank looks in the UK as well !
I have got a link for you to a site in which it says that solar tubes usually have an IR filter fitted to cut down the IR rays and ambient heat whilst allowing light in where you need it.
I have two installed as I say and have never had any problem at all (fingers crossed) with any sort of rain water leaks and believe me we get a fair bit of rain over here so I wouldn't see that as a problem.
I am not really sure what you mean by the Cathedral roof problem, these tubes are deigned to be very flexible in their design and there are numerous angles etc which can over come most situations. They can be fitted in most situations.
Here is the link to the forum, its in the USA but it gives some good information and may prove helpful to you
http://www.green-energy-efficient-homes ... -tube.html
I hope you get your light/heat problem sorted.
Regards
Gary
Check out my site at www.thermalleakdetector.org to see if any of my reviews might be able to save you a little bit of money. Every little helps as they say .....
thermalleak
Solar Supporter
Solar Supporter
 
Posts: 2
Joined: Thu Mar 31, 2011 6:44 am
Location: United Kingdom

Re: Skylights....any that pass Visible without IR?

Postby 470rigby » Fri Apr 01, 2011 8:51 am

thermalleak wrote: not really sure what you mean by the Cathedral roof problem

HI Gary,
Thanks for your input. With a Cathedral Ceilings there is no roof cavity. My house has exposed rafters with lining boards sitting on top, there is only a small space of about 50mm between the lining boards and roofing (the thickness of the battens), so there is no way that a light tube can be fitted.

Regarding the IR filters that can be fitted to light tubes. With a diffuser fitted, a reflective mechanism simply would not work, so I assume that they are simply material which is opaque to IR (absorbers of IR ...or some of it). If so, the absorbed energy has to be dissipated somewhere. Without some sort of cooling mechanism, I suspect that it would simply be re-emitted both skywards and inwards. In the absence of any data, the net effect could only be conjectured.

Cheers, Rigby
470rigby
Solar Crusader
Solar Crusader
 
Posts: 129
Joined: Tue Oct 06, 2009 10:57 am

Re: Skylights....any that pass Visible without IR?

Postby ghind » Thu Apr 14, 2011 6:01 am

I have a very green 3300m2 commercial bulding I've just finished with 50+ skylights in it.

Being in Tasmania in a supermarket with a negative cooling load (the fridges make it too cold even in summer it is so well insulated) we were not worried about incoming heat transfer. Heat loss is no good for us but incoming heat is no problem.

On our solartube skylights, they came with a special dome which stopped UV light and also captured the morning and afternoon light really well but was actually designed to cut back a bit on the peak afternoon sun.

We ended up changing the domes to let the peaks in, I just want as much light as possible and I don't care about heat gain.

These are excellent systems and I recommend them.

Greg
ghind
Solar Supporter
Solar Supporter
 
Posts: 19
Joined: Thu Jun 17, 2010 6:41 pm

Re: Skylights....any that pass Visible without IR?

Postby sandystone » Thu Apr 14, 2011 10:19 am

For heat- IR control, it might be worth looking at Velux brand.
As far as I know , they are the only ones who have options for Low-E, double glazed, argon filled, integrated blinds and the rest.
The good thing with these skylights, is that they can release heat from the warmest part of the room- the ceiling.
(no I don't collect any money in relation to this )
sandystone
Solar Supporter
Solar Supporter
 
Posts: 23
Joined: Tue Apr 12, 2011 11:28 am

Re: Skylights....any that pass Visible without IR?

Postby ghind » Thu Apr 14, 2011 10:34 am

roof.JPG

Here is a picture taken in March of my roof. The solar tube stuff is very good, I don't think they have shutters etc but the energy efficiency of it is excellent. It is a very tidy soltuion so there are two brands you can now look into.
ghind
Solar Supporter
Solar Supporter
 
Posts: 19
Joined: Thu Jun 17, 2010 6:41 pm

Next

Return to Alternative Building

Who is online

Users browsing this forum: No registered users and 2 guests

new solar power specials