Philips Fortimo LED light system?

[topgear17]

Basically am struggling to design a concept, me and my design team have to present a new project in 12 weeks (give or take) and me as part of a 3 man mechanical design team are struggling with research and developing our idea..

Basically we have to use the modern Philips Fortimo 2 LED, and develop an efficient system, Now we're being pushed down the road of increasing the LED's efficiency by cooling the LED itself, as this will in-turn increase the lifespan of the LED.

"LED's biggest problem is the heat it produces"

Now, one of the design team is really pushing for us to help use a water cooling system, like modern PC's have utilised in the past 5-10 years..


But am really struggling on both sides, i have to either come up with some sort of design that utilises water to cool the LED's, or create a solid argument against the water cooling system, and come up with a more feasible answer..

°As you can probably gather, am very new to this job , and really want to make a good impression as this is my first real project with this company, and I've kind of been thrown in at the deep end°

Thanks in advance for your help

 

[berkeman]

Basically am struggling to design a concept, me and my design team have to present a new project in 12 weeks (give or take) and me as part of a 3 man mechanical design team are struggling with research and developing our idea..

Basically we have to use the modern Philips Fortimo 2 LED, and develop an efficient system, Now we're being pushed down the road of increasing the LED's efficiency by cooling the LED itself, as this will in-turn increase the lifespan of the LED.

"LED's biggest problem is the heat it produces"

Now, one of the design team is really pushing for us to help use a water cooling system, like modern PC's have utilised in the past 5-10 years..


But am really struggling on both sides, i have to either come up with some sort of design that utilises water to cool the LED's, or create a solid argument against the water cooling system, and come up with a more feasible answer..

°As you can probably gather, am very new to this job , and really want to make a good impression as this is my first real project with this company, and I've kind of been thrown in at the deep end°

Thanks in advance for your help

You are correct that liquid cooling is a pretty extreme measure, and will present maintenance and reliability issues of its own.

What environment are you targeting for this LED lighting system? Outdoors? Indoors? Air flow?

If you can rely on some air flow and reasonable ambient temperatures, then your main task will be to get the heat out of the LEDs and to some sort of metal heat sink arrangement. Do the LEDs that you are going to use already come with some metal connections for heat sinks, or are they just 2-lead plastic LEDs?

 

[topgear17]

Thanks, sorry i didn't explain very well, the "system" is a indoor system, directly mainly towards the Education, and Office sectors.

The LED we have to utilise is this the phillips fortimo:

http://www.lighting.philips.co.uk/subsites/oem/product_pages/fortimo_overview.wpd

There are various heat sinks available, but they only dissipate the heat from the LED itself, and don't really cool the system at all..

I was hoping to design a system that cooled the product if possible..
As with most open market heat sinks these LED's in a working environment, when operating produce a heat of between 65'c-85'c now if we could reduce that to 50'c-60'c it would increase the LED's lifespan by 25%.

The challenge is basically to develop a modern, safe, efficient system utilising these Fortimo LED's in an office/ education environment..

Three key points to fit the criteria
1. Control the thermal issues related to LED engine (in my case the fortimo)
2. Lighting comfort, (Basically not an exposed LED, create a device that lights a large area evenly)
3. Product has to be surface, recessed, pendant or wall mounted.

 

[berkeman]

Thanks, sorry i didn't explain very well, the "system" is a indoor system, directly mainly towards the Education, and Office sectors.

The LED we have to utilise is this the phillips fortimo:

http://www.lighting.philips.co.uk/subsites/oem/product_pages/fortimo_overview.wpd

There are various heat sinks available, but they only dissipate the heat from the LED itself, and don't really cool the system at all..

I was hoping to design a system that cooled the product if possible..
As with most open market heat sinks these LED's in a working environment, when operating produce a heat of between 65'c-85'c now if we could reduce that to 50'c-60'c it would increase the LED's lifespan by 25%.

The challenge is basically to develop a modern, safe, efficient system utilising these Fortimo LED's in an office/ education environment..

Three key points to fit the criteria
1. Control the thermal issues related to LED engine (in my case the fortimo)
2. Lighting comfort, (Basically not an exposed LED, create a device that lights a large area evenly)
3. Product has to be surface, recessed, pendant or wall mounted.

Wow, those things are huge!

On the cooling issue, one thing you might explore is liquid cooling versus forced air cooling, and the relative reliability of pumps versus fans (I don't know which is more reliable). Interesting project.

 

[Studiot]

I was just discussing these or something similar today in relation to fire regs with a builder.

How much energy do you loose to the forced cooling system v the gain in efficiency for light output?

 

[topgear17]

If you could utilise a very efficient system for forced air cooling, for example..

Use suspended lighting system, that's all connected on one long track that's like a hollowed out pipe, that partially houses the back of the LED's, and then simply in all four corners have small fans sucking in cold air and pumping it around the sealed system, surely that would bring the thermal values down enough to run the LED's efficiency?

Same with water cooled system.. it wouldn't require fresh water on a regular basis, as because its flowing around the system it would stay reasonably cool, and once the lighting is no longer in use (IE, during strong daylight) the water would cool to ambient temperature?

 

[berkeman]

I was just discussing these or something similar today in relation to fire regs with a builder.

How much energy do you loose to the forced cooling system v the gain in efficiency for light output?

I think the issue is lifetime of the LEDs (and the associated replacement costs), rather than a lowering of efficiency with temperature. But I could be wrong on that.

If you could utilise a very efficient system for forced air cooling, for example..

Use suspended lighting system, that's all connected on one long track that's like a hollowed out pipe, that partially houses the back of the LED's, and then simply in all four corners have small fans sucking in cold air and pumping it around the sealed system, surely that would bring the thermal values down enough to run the LED's efficiency?

Same with water cooled system.. it wouldn't require fresh water on a regular basis, as because its flowing around the system it would stay reasonably cool, and once the lighting is no longer in use (IE, during strong daylight) the water would cool to ambient temperature?

Even with liquid cooling, you need a place to dissipate the heat, like at a radiator with a fan or other forced air cooling.

 

[berkeman]

I think the issue is lifetime of the LEDs (and the associated replacement costs), rather than a lowering of efficiency with temperature. But I could be wrong on that.

Indeed I was wrong on that:

http://www.ledsmagazine.com/features/4/8/1

Increased temperature does decrease light output.

 

[Studiot]

I was comparing the efficiency of LED to other lighting, not to itself at different temperatures. It is interesting to know about the effect of cooling though.

The point is that the electrical power going into LED luminaires either appears as useful light or heat.
With other forms the power going in appears as useful light, nonuseful electromagnetic emission and heat.
So although the LED is more 'efficient' in that a greater % of the input appears as useful light, it also generates a greater amount of heat. This was not fully realized in early designs.

I think (but can't remember) if it was here or at AAC but I posed a thread + link, a few months ago, to a components trade magazine discussing the number of electrical fires caused by LED lights in buildings and the resulting changes needed to the regulations.

 

[topgear17]

Indeed I was wrong on that:

http://www.ledsmagazine.com/features/4/8/1

Increased temperature does decrease light output.

Yea this is exactly why i think if i find a solid efficient method of cooling the LED's it will be a great advantage over other design systems currently in place.


As for the heat loss (wasted energy) i spent a little time trying to think of a logical efficient method to harness this, but its not really feasible within my timescale..

And within my design i have to use the Fortimo LED in the link above.. so i have to try and resolve a solution for its weakness.. HEAT! and 99% of other LED's weakness for that matter...

So.. if i was to go along the water cooled route, i'd still need a radiator or some sort of something to dissipate the heat from the water.. ? Hmmm...

Anyone think this is a waste, going water cooled? or has any better, more feasible ideas? FIRE AWAY

 

[pantaz]

There are scores of hobbyists building high-power LED projects. I suggest looking at how they're dealing with heat dissipation.

http://www.candlepowerforums.com/vb/content.php
http://www.instructables.com/
http://www.makezine.com/

 

[topgear17]

Thanks, i'll check those out tonight :)

 

[Studiot]

Here are some commercially available high power LED lumieres that address the cooling issue.
Note the cooling ribs on the fitting.

These also have full IP65 / fire ratings


This is not the place for advertising so I can't post more details but the catalogue has all the design information needed.

 

[berkeman]

This is not the place for advertising so I can't post more details but the catalogue has all the design information needed.

I'm okay with you posting links to this info, Studiot. I'm interested in learning more as well.

 

[Studiot]

http://www.halers.com/led_downlights/10765_0c.html

I see the website catalogue is undergoing revision.

 

[topgear17]

Thanks mate..

really useful links :)