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2006-05-30 Home Front Economy

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Posted by mhw 2006-05-30 08:48|| || Front Page|| [5 views since 2007-05-07] Top

#1 mhw, be a darling and make sure to let us know when we can start buying these to replace the regular lightbulbs at home? I've gone to compact fluorescents where I can, but am looking forward to enriching your family and fellow shareholders as soon as Mr. Wife can be pursuaded that the pay-out time is reasonable. Thanks for keeping us informed!!

Posted by trailing wife 2006-05-30 09:48|| 2006-05-30 09:48|| Front Page Top

#2 Energy saving bulbs only save energy in summer when the extra heat of filament lights are a waste.

Posted by Bright Pebbles 2006-05-30 11:29|| 2006-05-30 11:29|| Front Page Top

#3 some stuff is already for sale

see: http://www.superbrightleds.com/edison.html

but to be honest they aren't that good yet; the next generation of products will be quite a bit better but will probably require another two years or so to reach the retail market;
also, the compact fluorescents now for sale are pretty good for many applications (e.g., table lamps).

the most promising market for LEDs is commercial - the amount of lighting needed in offices and industrial sites and malls is huge and LEDs can be installed in all kinds of decorator styles; the other bonus is that the air conditioning requirement created by the waste heat of lighting is also huge.

Posted by mhw 2006-05-30 11:32|| 2006-05-30 11:32|| Front Page Top

#4 bright pebbles

that may be true in a residential dwelling with 365 day climate control however,

In many offices, industrial buildings, etc. the heat load from lighting, computers, coffee makers, people, etc. creates a heat surplus most of the year; in southern states the heat surplus is a 10-11 month event

Posted by mhw 2006-05-30 11:48|| 2006-05-30 11:48|| Front Page Top

#5 The cost savings realized by conversion from incandescent lamps to LEDs is so significant that most municipal corporation yards go out and switch over traffic signal indicators even before the incandescent bulb burns out. When you factor in the reduced amount of heat emission (and consequent thermal cycling of the fixture and related equipment) the reduction in detrimental effects to both environment and capital equipment is tremendous.

Posted by Zenster 2006-05-30 11:57|| 2006-05-30 11:57|| Front Page Top

#6 One thing I haven't understood about LED lighting is why they are still individually packing each LED. It seems much cheaper to produce grids of LEDs and use a lens to obtain the desired light pattern.

Posted by ed 2006-05-30 12:01|| 2006-05-30 12:01|| Front Page Top

#7 The other thing most folks don't think about when it comes to lamps is the labor cost. In an office setting, the labor to install the lamp can be 80% of the cost.

High bay lighting that requires scaffolding can be ridiculously expensive to change. Many places will also use a group relamping strategy and just replace all the lamps in a building or floor in one fell swoop. Cheaper than having some guy come out and replace them as they fail one by one.

Posted by Dreadnought 2006-05-30 12:39|| 2006-05-30 12:39|| Front Page Top

#8 It seems much cheaper to produce grids of LEDs and use a lens to obtain the desired light pattern.

Already being done. Exact configuration depends on the application. Check out the LED flashlights next time you go shopping for an example.

Posted by SteveS 2006-05-30 13:17|| 2006-05-30 13:17|| Front Page Top

#9 the long life of LED is, as noted above, a big advantage

in theory, there is no obvious barrier to producing devices with a lifetime of 100 years... there is, however, a barrier to testing devices to assure that they have long lifetimes

one of the marketing/certification problems that CREE and others have to overcome, is to develop a combination of physical testing and simulation that has enough credibility to be used to say that the product has the lifetime they say it has

Posted by mhw 2006-05-30 13:32|| 2006-05-30 13:32|| Front Page Top

#10 mhw, accelerated lifetime device reliability testing already does that and has been in use with well-established results for a very long time. Running a device to end-of-life failure at 125-150% power levels can give you a very accurate assessment of its nominal power lifetime duration.

Posted by Zenster 2006-05-30 13:44|| 2006-05-30 13:44|| Front Page Top

#11 Steve,
All my LED lights are composed of discrete LEDs, each in its own packaging and lens that is then mounted in some pattern through a reflector. That seems expensive and wasteful. I am talking about an LED strip that is in one package/lens combo. Extend that for the 2-D for an area emitter, though a large 2-D emitter will likely heat dissipation problems, a 1-D strip's heat dissipation should be easily manageable. This was done for the semiconductor lasers I used more than 10 years ago.

Posted by ed 2006-05-30 13:45|| 2006-05-30 13:45|| Front Page Top

#12 Well, on my last Space Shuttle trip, heat dissipation wasn't a problem......

Posted by mcsegeek1 2006-05-30 14:41|| 2006-05-30 14:41|| Front Page Top

#13 zen

It is true that you can simulate, say 5 years, by running the device for, say 1 year, at higher than rated power levels and rely on calibration based on a standard test procedure done for 5 years which compared the 5-year normal power and the 1 year extra power.

However, no such calibration has been done to measure a 100-year normal power device against a 2 year test of extra power (not to mention the problem of whether the company will be in business in 100 years to honor its warranty). I may believe an extrapolation from the 5 year/1 year test combined with some other test. You might believe such an extrapolation. The question is whether the wholesaler will believe it.

Posted by mhw 2006-05-30 14:47|| 2006-05-30 14:47|| Front Page Top

#14 Considering how they now have LEDs that successfully operate in the automotive environment (one of the most grueling [i.e., shock, vibration, solvents, thermal cycling etc.] besides deep-space), I'd wager that the relatively benign household applications won't pose too much of a problem. Overall, this is nothing that a nice warranty package can't solve, regardless of actual device lifetime.

Posted by Zenster 2006-05-30 16:24|| 2006-05-30 16:24|| Front Page Top

#15 Time for a dose of reality.

Call me when they are affordable. I can get compact flourecents for a buck each if I shop or get them on sale.

The cost needs to come way down. These devices are just too costly to be realistic as a replacement for current lighting in most cases. Last time I checked I saw one for 25 dollars. It was the cheapest I found. Having not have any real personal income since 1999 this not an item I will be purchasing anytime soon.

Posted by Sock Puppet of Doom 2006-05-30 16:32|| 2006-05-30 16:32|| Front Page Top

#16 The cost needs to come way down.

Capitalism and the economies of scale are your friends here. Think about VCRs or DVD players. The early adopters paid about a kilo-buck. The first consumer models were around $500. Today you can buy one for tens of dollars. Lasers did the same thing as they went from expensive laboratory experiment => solid state device => cheap component in consumer electronics. If there is a buck to be made, it will happen.

Posted by SteveS 2006-05-30 18:52|| 2006-05-30 18:52|| Front Page Top

#17 If there is a buck to be made, it will happen.

This is why I mention a warranty program as the solution to product lifetime issues (think Craftsman tools). Gotta love capitalism.

Posted by Zenster 2006-05-30 20:33|| 2006-05-30 20:33|| Front Page Top

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