TSER vs IRR

[Guest swong2046]

What is Total Solar Energy Rejection (TSER) means?

What is the different between TSER & Infrared Rejection(IRR)? Both also are heat rejection?

Really confuse...

Is there a way to calculate the TSER% if UVR+VLR+IRR % provided?

Anyone?

[Guest ZergRush]

TSER is an industry recognized performance value, infrared rejection is not. TSER is the percentage of all energy from the sun reflected away from a window, as well as the percentage absorbed by the window and released back outdoors.

There are many problems with so-called "infrared rejection", such as the fact companies selectively choose which parts of the spectrum they report and IRR does not include absorption- an important contributor to heat gain. For instance, a certain large company reports this for only a small part of the spectrum which is less than 10% of the actual infrared wavelengths. Some other companies report this at only one wavelength! So they call it "infrared rejection", but really it is only a small part of the total infrared and is not representative of the actual infrared energy. Also, manufacturers of some products that have very high absorption report IRR because it does not count absorption against it. The TSER is the "true" heat rejecting value fo a film, because it takes the entire solar spectrum into account (infrared is only 49% of the solar energy anyway), and also includes the effects of absorption. The National Fenestration Rating Council is the the only third party window rating system. It is recognized by Energy Star, utility companies, and U.S. and Canadian governments. They only recognize SHGC/TSER. They do not recognize IRR.

In short, IRR is a misleading marketing gimmick.

The International Window Film Association also has a memo pointing this fact out, so check their web page out also. Additionally, CPFilms and Solar Gard have each written good white papers explaining why these claims are bogus (found on their technical pages). I highly recommend you read them.

-ZR

Edited March 19, 2010 by ZergRush

[Sisqouc]

ZergRush did a good job and I concur.

You may also have heard some claims that the film they are pitching will reject more heat at angle on hot summer days when the sun is more directly overhead. That claim too is suspect as even untinted glass would bounce some heat at extreme angles.

For some reason their is a rouge group of folks in this one film manufacture who are hell-bent on destroying a household name with bogus claims.

Perhaps they believe we are living in the end of days times.

[masterrider]

So basically make sure your films are NFRC rated and then compare them using TSER (higher is better) or SGHC (lower is better) and ignore all the other stuff if you are just looking at performance.

[Tinitman]

What is Total Solar Energy Rejection (TSER) means?

What is the different between TSER & Infrared Rejection(IRR)? Both also are heat rejection?

Really confuse...

Is there a way to calculate the TSER% if UVR+VLR+IRR % provided?

Anyone?

Yes there is a way to calculate it. I do not remember where I have my notes from 15 years ago but if I remember correctly the formula is from ASHRE.

Why do you need to calculate it? What information are you tryng to retrieve?

And no tser and ir are not percentages of heat rejection. IR is a light wave and at best accounts for a little more than 50% what causes heat. Also, the IR numbers that are listed by the manufacturers, where are they testing it? IR ranges from 750nm to 2500nm. Many manufacturers only test between 900 to 1000nm giving a false performance in my opinion.

Like mentioned above, tser is a more accurate measurement of heat rejection. Actually solar heat gain coeffecient is the best performance number according to the NFRC.

[kats2112]

So basically make sure your films are NFRC rated and then compare them using TSER (higher is better) or SGHC (lower is better) and ignore all the other stuff if you are just looking at performance.

In a nutshell.

[Guest tintjam65]

TSER is calculated using solar absorption, solar transmission and solar reflectance in reference T-sol (total incident solar energy or sun energy at the glass exterior)

Like its been said infrared is only 49% of T-sol, visible light another 49% and converts to heat once it strikes an object, UV <2%

IRR can be calculated using the entire IR spectrum, but also must account for reflectance, absorption and transmittance to be accurate

A prestige film may state 97% IRR but in reality when calculated correctly using all IR wavelengths it = more like mid-60s IRR

[Guest vclimber]

IRR is not a very accurate measurement... it should be IRT if you are going to attempt to quantify a film's ability to filter out that spectrum.

[Guest swong2046]

What is Total Solar Energy Rejection (TSER) means?

What is the different between TSER & Infrared Rejection(IRR)? Both also are heat rejection?

Really confuse...

Is there a way to calculate the TSER% if UVR+VLR+IRR % provided?

Anyone?

Yes there is a way to calculate it. I do not remember where I have my notes from 15 years ago but if I remember correctly the formula is from ASHRE.

Why do you need to calculate it? What information are you tryng to retrieve?

And no tser and ir are not percentages of heat rejection. IR is a light wave and at best accounts for a little more than 50% what causes heat. Also, the IR numbers that are listed by the manufacturers, where are they testing it? IR ranges from 750nm to 2500nm. Many manufacturers only test between 900 to 1000nm giving a false performance in my opinion.

Like mentioned above, tser is a more accurate measurement of heat rejection. Actually solar heat gain coeffecient is the best performance number according to the NFRC.

I'm trying to compare the specs from diferrent tinted shops but most of them has higher IRR (~90%+) but lower TSER (~60%+). Need to check how to calculate the TSER as it is not correct that I calculated like this:

TSER%= 44% x VLR%+ 3% x UVR%+ 53% xIRR%

Any advice? as I dont want to be con by those supplier

[Tinitman]

Are the brands you are referring to on the NFRC web site? You can search here http://cpd.nfrc.org/search/apd_film/film_search_default.aspx

They rate everything at a 90 degree angle. Some manufacturers boast higher perventages at different angles. But that is a different story.

If you are looking at heat rejection for a building, look at the solar heat gain coeffecient. The NRFC does not identify IR in their calculations.

If the brand you are looking at is not rated by NFRC, most likely the numbers are stretched a tad