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Biden admin moving forward with light bulb bans in coming weeks

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coppice:

--- Quote from: Gyro on April 03, 2023, 09:00:31 pm ---The first time I held a spectroscope up to a bog standard diy store  LED lamp, I was struck by how continuous the spectrum actually is. None of the spectral peaks that you get with a florescent. The phosphors are actually pretty good these days. Obviously as you go towards the cold end of the spectrum colour temperature range, you'll get more of the LED blue fundamental showing through.

--- End quote ---
Fluorescent tubes vary enormously. Most are made for decent efficiency, and compromise on colour. However, that can get you into a lot of trouble in some places. Clothing stores are a good example. Poorly chosen tubes in those places cause a flood of "it didn't look like this when I bought it" returns. An executive in one of the UK's biggest clothing retailers lost his job by screwing up a bulk order for tubes which caused mass clothing returns. For decades the best colour rendition available in a light for artists was a rather inefficient fluorescent tube called "graphic". It used different glass to get a the intensity of those 2 main mercury lines down, and a phosphor mix chosen for accuracy over efficiency. They were generally driven from an electronic ballast, to eliminate flicker.

Nusa:
Several things incandescents are better at:
1) Surviving hot environments, such as providing illumination inside an oven. Or in old fixtures that have ZERO ventilation (the fixture was designed for the heat, but the alternative bulbs die from their own heat -- found out the hard way.)
2) Being used as load resistors, with feedback, also known as a dim bulb tester.
3) When being used for their secondary function, providing heat rather than light. They're rather good at it.

That said, modern LED's have gotten acceptable, and I use them for lights I use regularly. Lights I use less than an hour a year I've never bothered to change. Nearly all the closets still have old-school 100W bulbs in them. Even counting electricity, they aren't cost-effective to change at this time.

SiliconWizard:

--- Quote from: james_s on April 03, 2023, 08:59:24 pm ---
--- Quote from: Zero999 on April 03, 2023, 08:46:42 pm ---I suppose the question is: there may be advantages of incandescent for some, but are they really worth the extra running cost?

Is the law really necessary? If only a tiny minority of people use incandescent, then it's not going to make much difference in the grand scheme of things.

An alternative to banning, would simply tax them so they cost the same as LED.

--- End quote ---

For me, no, the energy savings outweighs the handful of disadvantages, but that's a personal decision that I have no right to make for others.

--- End quote ---

Yeah. I'm more mixed about that. The energy savings are dramatic. That's for sure. I have replaced lots of 50W halogen spot bulbs with 6W LED spot bulbs, and these are actually much brighter. Crazy.

Now I'm not so happy with the light they provide. I have selected warm white ones, but even with those it looks clinically cold. Cold white ones are of course even worse. I haven't found anything that looked "better" for my taste/use cases so far. Or you'd resort to RGB LED bulbs to get the white tone you want but which are much less bright, and more expensive, so not that great of a deal.

Then there's the flickering as you mentioned. Not all are created equal of course, but if you want zero flicker then you have to buy specific stuff, Philips makes such stuff. Still expensive. Constant current DC  LED drivers.

I don't miss the heat coming from halogen bulbs, but I kinda miss the light they emit.

BrianHG:

--- Quote from: james_s on April 03, 2023, 08:53:22 pm ---
--- Quote from: coppice on April 03, 2023, 06:08:28 pm ---Huh? Incandescent lamps flicker. Its 100Hz/120Hz and doesn't go anywhere near zero, but its there. A decent LED has a really steady output.

--- End quote ---

Come on, don't feign confusion, you know what I'm talking about, a few years ago after a similar debate came up and people insisting that the bulbs didn't flicker I connected a photodiode to a scope and demonstrated it. Out of a random selection of LED bulbs I grabbed, most of them flickered, some sharply, some at mains frequency, some at the driver frequency, some both. The flicker form an incandescent lamp is negligible, just a little 120Hz noise on the top of a smooth line, the thermal inertia of the filament provides a great deal of filtering. Next to one of the flickery LED bulbs (the filament type with no space for a proper driver are typically the worst) the difference is like night and day. Maybe I should have used the word "strobe" instead of flicker. Many LED lights strobe, some do not but many do, incandescent bulbs do not, even the cheap ones. For this reason I always buy a sample of a particular bulb so I can evaluate it for my needs before I buy more of them. As I've said many times, I have long been a big fan of LED bulbs, but I don't pretend that they are flawless, the light quality can be good, but it's not better, they simply do not have a full spectrum and even the best cannot achieve a CRI of 100, this is a fact.

--- End quote ---
This depends on the bulb's design.  I can find bulbs with a filament which has a deep modulation due to a thin spaced out long filament VS a tightly wound high wattage thick filament which holds it's temperature by means of slowly fading out when the power is cut.  Also, for the faster cooling filaments, the 100hz flicker is worse in the blue part of the spectrum compared to the red.

coppice:

--- Quote from: BrianHG on April 03, 2023, 11:43:33 pm ---
--- Quote from: james_s on April 03, 2023, 08:53:22 pm ---
--- Quote from: coppice on April 03, 2023, 06:08:28 pm ---Huh? Incandescent lamps flicker. Its 100Hz/120Hz and doesn't go anywhere near zero, but its there. A decent LED has a really steady output.

--- End quote ---

Come on, don't feign confusion, you know what I'm talking about, a few years ago after a similar debate came up and people insisting that the bulbs didn't flicker I connected a photodiode to a scope and demonstrated it. Out of a random selection of LED bulbs I grabbed, most of them flickered, some sharply, some at mains frequency, some at the driver frequency, some both. The flicker form an incandescent lamp is negligible, just a little 120Hz noise on the top of a smooth line, the thermal inertia of the filament provides a great deal of filtering. Next to one of the flickery LED bulbs (the filament type with no space for a proper driver are typically the worst) the difference is like night and day. Maybe I should have used the word "strobe" instead of flicker. Many LED lights strobe, some do not but many do, incandescent bulbs do not, even the cheap ones. For this reason I always buy a sample of a particular bulb so I can evaluate it for my needs before I buy more of them. As I've said many times, I have long been a big fan of LED bulbs, but I don't pretend that they are flawless, the light quality can be good, but it's not better, they simply do not have a full spectrum and even the best cannot achieve a CRI of 100, this is a fact.

--- End quote ---
This depends on the bulb's design.  I can find bulbs with a filament which has a deep modulation due to a thin spaced out long filament VS a tightly wound high wattage thick filament which holds it's temperature by means of slowly fading out when the power is cut.  Also, for the faster cooling filaments, the 100hz flicker is worse in the blue part of the spectrum compared to the red.

--- End quote ---
I'm used to 230V bulbs. US ones probably flicker less. Try looking at the THD in the current waveform or power consumption of a 230V incandescent bulb, when fed with a clean voltage signal. Many are over 20%. That's a clue to much that filament is heating and cooling every half cycle of the mains, and how much the light output is modulated.

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