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One result of the success of LEDs is the large reduction in available ceiling fixtures that take replaceable bulbs (incandescent, LED or any other type). I went to Menards to buy a surface mount light fixture the other day, and fixtures with built-in LEDs have largely supplanted fixtures with replaceable bulbs. I really don't want to replace the entire (perfectly good) fixture when a capacitor blows, but that's what is largely being offered for sale. I still wish manufacturers would come up with a standard LED light element for use in fixtures so we could avoid the cost, hassle, and extra landfill waste of throwing away entire fixtures rather than the electronic elements when they fail. I absolutely do not believe we'll see the claimed multi-decade service life for those circuits, but even if we do--why throw the whole thing away?
Agree. I've designed a solution to this (in my head only). The LED element and driver would be separate. The LED elements would have a standard base with 3 pins. One pin is common ("ground"), one is power in, and the third would be a resistor to ground, the value that would indicate to the driver circuit the max current current to provide.
The driver would be a constant current source (which is what LEDs 'want'), with the max current determined by that resistor, and optionally, a dimmer could reduce the current below max.
This would physically separate the driver from the LEDs, so heat from one doesn't affect the other, extending life (more on this below). Placing the driver in the base would actually give the manufacturers more flexibility as the LED element would be smaller, and everyone would benefit from standardization and economy of scale. LED or driver or fixture could be replaced, w/o having to replace any other component. That is good for the environment. I bet those fixtures that get thrown away took more energy to make than was saved by the LED.
LED life - those 'lifetime' numbers on the box are bogus. That's not life at all as we would think of it, that advertised number is based on how long it would take an LED to dim to 80%, based on a short term test (weeks?). That might predict 20,000 hours, but if the driver circuit goes bad after, say 1000 hours (usually because a capacitor goes bad from the localized heat), sorry Charlie, that doesn't count. And that's why it's good to separate the LED element from the driver - w/o needing to cram it all in the space of an old bulb style, they can manage heat much better.
Thanks for that info, I didn't know that the nominal bulb wattage included power for the ballast. That's surprising, since the wattage consumed by the ballast is independent of the bulb (i.e. an old 60 hz magnetic ballast is less efficient in its own operation AND it decreases the efficiency of the bulb compared to a newer, higher-frequency electronic ballast) . The efficiency of the ballast to be used with the bulb can't be known by the bulb manufacturer.
I won't miss CFLs at all--good riddance. I don't intend to dump all my incandescent bulbs, though. ...
And they mention those tests were done at low frequency, so I assume 50/60 Hz line frequency, and they probably haven't updated the test since the old days, so just use the magnetic/transformer ballast. I'd imagine there are newer test for the new ballasts in addition. I'm reading that the electronic 'ballast' are ~ 10% more efficient, considerable since the tubes with old ballast are already rated pretty high (10% of 60%~70% is significant, 10% of 5%, not so much!).
I have some CFLs left, but they get replaced with LEDs as they die.
Another place I need the old filament bulbs is where we have the LEDs on dimmers. Even with dimmable LEDs and LED/CFL rated name brand dimmers, the LEDS act weird on some dimmer settings, the output randomly fluctuates. The manufacturer "solution" it to put their resistor in the fixture (which wastes power!). I had multiple bulbs on each dimmer, so I replaced one of the 2 or 3 with filament, and that created the load the dimmer needed to function correctly.
Makes me appreciate the simplicity of the old filament bulb, but the LED efficiency is nice. And actually, the processes of making that "simple" filament bulb are amazing - they have really engineered and dome materials science to develop that filament and the gasses. The filament is actually a coiled-coil, which gives more surface area/light. It's amazing, if you are into those sorts of things.
-ERD50
