Efficiency of Luxeons v. other lights

[_Wayne_]

I currently use a 300-watt halogen torchiere-style (reflecting off the ceiling) light for the living room. Would it be at all practical to use LS's (1-watt?, 5-watt?) to do the same thing?

If LEDs use 1/3 the power of halogen for the same amount of light (and I don't think they're NEAR that efficient), it's still take 20 5-watt Luxeons, which would be, um, EXPENSIVE.

[paulr]

Yeah, and you probably don't want that phosphor color spectrum. If you do, use a fluorescent light, for heavens sake. It will be far more efficient than the halogen or LED's.

[highlandsun]

Expensive as all heck, yes. I spent $260 on 18 Luxeon 1W stars. It's a solution that really isn't practical (yet) from a bottom-line analysis. You have to really really want them for no rational reason at all (like me) to go this route.

I'm switching a bunch of my incandescents to compact fluorescent. I still have a 300W halogen in the living room and in my bedroom though.

[Jonathan]

If the goal is the production of _white_ light, then there really is no good reason to switch from a 300W halogen to LEDs.

Halogen lamps get more efficient as they go to higher wattages, whereas for LEDs you need lots and lots of heat sinking as you go to higher wattages. The net result is that I'd expect the 300W halogen to be _more_ efficient than the LEDs.

If you really want efficiency for white light production at these scales, then go with metal halide or fluorescent lamps.

But there are aspects of lighting other than efficiency of white light production that make halogen attractive, and these might make LEDs potentially useful.

One of these is operating large halogen lamps at low power levels to get 'mood'. People will regularly turn their big halogen lamp down to 1/4 brightness or less to get just the right 'mood'. The problem is that for a halogen to put out 1/4 brightness, it needs to consume 1/2 power; in other words for 50% power you get 25% output at half the efficiency.

If you do this lots of the time, then perhaps a mix of colored LEDs selected to produce the same 'mood' effect might be much more effective, and efficient, especially when you consider that the red and orange LEDs are about twice as efficient as 'white' LEDs.

Another thing to do, if you specifically want the desirable spectral characteristics of the halogen lamp, is to look for Infra-Red Recovery halogen lamps, which use an IR reflective coating on the inside of the envelope, to reflect some of the IR back to the filament. These are about 25% more efficient than standard halogen lamps. I know that GE makes such lamps for 300W halogen.

-Jon

[_Wayne_]

... since it seems their advantages are ruggedness and efficiency at small sizes.

I have a reading lamp that is definitely some kind of HID. I believe it's MicroSun brand. I'd love to know exactly what kind of technology/bulb it uses to see if the bulbs are cheaper from third parties.

It's just that LEDs are so intriguing in ways that flourescent and HID aren't. Unless maybe they begin putting out Mercedes-style, quick-start technology HID lights that somehow fit in standard fixtures. That'd be cool!