What is the next big thig in LED technology?

[Lynx_Arc]

A few years ago when I last really looked into the category, it was impossible to find mains-powered LED tubes at big box home centers.

Hyperikon was a reliable source on the 'zon, but it seems they shut their doors in June 2020. I gather that Satco is a reputable make - they don't sell direct so scouring their site for candidate part numbers to hit up online retailers with is recommended. Note that a great many of their products require ballasts or external drivers so read descriptions carefully. Efficiencies are better than floro, but not mind-blowing - the main benefit is the considerable lifespan increase and the removal of a ballast from the system.


I gather that there are several distinct topologies of electronic ballast and making a LED tube that's nominally compatible with more than one is ... difficult.


If the thing lasts a good 10 years in service, that's arguably a step up on the annual relamp cycle that floros typically demand for 24x7 operation typical in commercial/industrial settings. However such extravagances are seemingly limited to retail and upper-tier office spaces - elsewhere more utilitarian linear fixtures will likely be retrofit continuously until no longer economically feasible or their host building is gutted or demolished.

From what I'm thinking the addition of a ballast in the circuitry would reduce efficiency somewhat, and I agree if you aren't replacing tubes but every 4-5 years or more then retrofitting may be not really be a good investment. It sort of reminds me of when LEDs would be improved from something like an XML to XML2 and so on, upgrading the LED in your light for just efficiency wasn't worth the trouble most of us wanted more than 10-20% increase, for me 50% increase would be a starting point and in the flouro to LED conversion 20 extra lumens/watt doesn't cancel out a lot of work and costlier components. I wouldn't consider 120 lumens/watt worthwhile if It only saves me less than a dollar a year in power because my usage isn't high. When I was considering replacing a 4 foot flourescent T12 fixture with LED I first looked at prices of LED tubes and at $20 for a pair vs about the same for a native LED fixture that was higher output that the tubes were and the fact I have a few t12 tubes I bought used for $1 each from the Habitat for Humanity store about 5 years ago I decided to wait till those tubes or the ballast dies before bothering with it all
The sad thing is you can't get screw in bulbs for decent prices at all with nearly as much efficiency a 4 foot LED tube is a lot better deal than a screw in bulb.

 

[Lynx_Arc]

Having done some modest experimenting with fluorescent fixtures and "retrofit" T8 4-ft. LED tubes I concur it is hit-and-miss. First case, instant-start electronic ballast, none of several brands of LED tubes worked, including Philips; but neither fixture nor tubes were defective, everything brand-new. Makes you wonder how retailers are faring with customer returns which "don't work".

Bothersome trend in my view is fixtures with non-replacable tubes/LEDs. If/when it goes (or even part) the whole thing apparently gets taken down and tossed. Not sure if we should trust their lifetime estimates? I did buy a single-tube equivalent which is scarcely larger than the tube itself (oversized end caps) which is the the least of the evils.

As for LED raw efficacies, according to what I've read, limit could end up closer to 250 lumens/W than 300 or higher. In that case we may be approaching this as a recent Samsung LM301B is spec'ed around 220 lumens/W albeit at low power (0.2W) and CRI (70).

Dave

That is sort of an issue for me, Buying a native LED fixture vs retrofitting a fluoro one with LED tubes. If the cost of the new fixture is cheaper than the price of tubes alone and you don't have to worry about ease of swapping out a fixture and the LED fixture lasts 10-20 years then it may be better to go native especially when the light distribution is more optimal than swapping in LED tubes. The one advantage of LED is you don't have to match flouro fixture sizes to match output so unless you have a drop in ceiling grid that needs to fix right for cosmetic needs you could hang a smaller fixture that has more lumen output and essentially upgrade your lighting. What I would like to see is them to have dimming feature in fixtures for dirt cheap not a lot more cost that way you can turn on a light at 10% or 50% output and run it that way till full output is needed. This would make up for not an overly impressive efficiency difference as a flourescent fixture putting out 5000 lumens could be replaced by one that does from a few hundred lumens to let's say 7000 lumens and running it at 2000 lumens may be plenty most of the time saving you 60% on power. I've been to new construction with new LED lighting that the lights have motion sensors that turn them on and off when you enter which can be power saving but I would like to see instead of on/off immediately turning them down to low for a longer time period before shutting off as (to me) having lights on in one area you are in and looking into a dark room and then it lights up brightly screws with your vision as it has to double adjust from bright to dark to instantly bright again in but a few seconds.

 

[idleprocess]

From what I'm thinking the addition of a ballast in the circuitry would reduce efficiency somewhat

For most, the issue isn't electrical efficiency so much as reliability - the ballast is just something to fail that doesn't need to be there. For a business there's a cost associated with that nuisance, with the labor being greater than the BOM on the invoice.

When I was considering replacing a 4 foot flourescent T12 fixture with LED I first looked at prices of LED tubes and at $20 for a pair vs about the same for a native LED fixture that was higher output that the tubes were and the fact I have a few t12 tubes I bought used for $1 each from the Habitat for Humanity store about 5 years ago I decided to wait till those tubes or the ballast dies before bothering with it all

I can't speak to personal priorities and circumstances, but for me the reliability is the main attraction. I don't like tubes going out randomly nor the unknown lifespan of the ballast (cheaper electronic ballasts seeming not to last as long as old-school magnetic ballasts). i.e. Since I've presently got one two of six tubes out in the garage I might as well upgrade all three fixtures while I'm at it.

 

[JustAnOldFashionedLEDGuy]

What's available at Home Depot is not indicative of the market. Vast majority of tubes are sold through industrial sales for commercial use. A single floor retube couple deplete all the stock at an HD or 3.

 

[Lynx_Arc]

For most, the issue isn't electrical efficiency so much as reliability - the ballast is just something to fail that doesn't need to be there. For a business there's a cost associated with that nuisance, with the labor being greater than the BOM on the invoice.


I can't speak to personal priorities and circumstances, but for me the reliability is the main attraction. I don't like tubes going out randomly nor the unknown lifespan of the ballast (cheaper electronic ballasts seeming not to last as long as old-school magnetic ballasts). i.e. Since I've presently got one two of six tubes out in the garage I might as well upgrade all three fixtures while I'm at it.

My fixtures have old school ballasts in them and I have an extra light fixture and extra tubes so I would have to have 3 tubes fail and 2 ballasts to need to replace the one working light I still have in service.

 

[treebev5]

How is the brightness a problem? Are they too bright or lacking in brightness? The problem you describe was prevalent perhaps 15 years ago when multi 5mm LED lights were norm but LEDs have gotten a lot more efficient and brighter, nowadays there are countless high quality single Emitter LED lights available which offer good throw characteristics. Its true that LED setups will not match incandescent lamps with same overall output in terms of throw since the filament of bulbs is so much smaller then surface area of LED. But even so modern LED throw very well and usually have much highter total output then same size incan flashlight while maintaining constant brightness and good runtime. Single battery LED lights will often advertise thousands of lumen, but those are ANSI ratings and are usually only maintained for 30 seconds to a few minutes without active cooling before step-down. Up to 1000 lumen on a single cell can be maintained quite well with modern LEDs and high cap, high drain Li-ion batteries.

Thank you for replying to my post. So, I would say that they need to be brighter, but, more specifically, that the LED light sources lack singularity--as you mentioned, the light appears from a number of different beads, rather than appearing to come from a point, or a very small volume of space.

I am surprised at the distance placed between the beads, although this is likely due to heating concerns. But the results is a muddy sort of lighting, and without a diffuser plate you can even see multiple shadows cast.

Please note that I mean no disrespect and I am excited about the promise of LED lighting and own several, but I do think people should appreciate the quality of all different sorts of lighting, going back to carbon arc lamps. Thanks.

 

[treebev5]

None of my LED flashlights has more than one LED. As far as quality of light, this is more a marketing issue than a technology issue. Modern LEDs are capable of excellent color rendition, but because those LEDs tend to be less bright or perhaps less efficient than LEDs with inferior color rendition, guess which ones the manufacturers of flashlights use more often?

The Fenix PD36 TAC I just got will run over 10.5 hours at 350 lumens on a 21700 battery. It has a single LED that can produce up to 3000 lumens maximum. I've never before owned a flashlight with this much sustained brightness, and I find the light quality acceptable.

That's a great point. I wasn't aware that many LED flash lights are powered by a single LED. I guess my concern is, why haven't those LEDs migrated to, say, architect swing lamps with LEDs?

 

[treebev5]

Next big thing I'd like to see is run time catch up to lumens. A real 500 lumens for 10hrs in a general purpose sized light would be a good goal.

I doubt our LEDs are nearly as efficient as they are bright. Or if that's not the case less power loss as heat at the higher out puts. At least then peak out put could be more than a marketing point. ( Side note a better FL1 standard where run times are based on start up to a loss of 10% of brightness instead of only 10% of brightness left would be nice) Still that would likely lead to problems as a 4K/L light w a 5K/mah 21700 would eat batteries like candy.

Maybe the next big thing are better control boards. Either way we shouldn't overlook how good we have it right now

I don't know much about what you're talking about. Do you mean that we should test the bulbs in one run until they emit 90% of brightness instead of to when they're only at 10% brightness?

Also, I saw a swing-arm lamp that had some vents in the top, as well as some lamps that have holes in the middle to move heat away from the LEDs. How about a little fan in the lamp to blow heat away?

 

[idleprocess]

That's a great point. I wasn't aware that many LED flash lights are powered by a single LED. I guess my concern is, why haven't those LEDs migrated to, say, architect swing lamps with LEDs?

LEDs being more efficient at lower currents, triples and quads are pretty common whenever throw isn't a priority.

 

[treebev5]

Reasonable ANSI standard would be to 70% total output after 1 hour. Drop to 70% is likely imperceivable to vast majority of users, less then that quickly becomes noticeable. 4k lumen cannot be maintained on single 21700 without active cooling for longer then few minutes. In this case more thermal mass and passive cooling fins will increase runtime but not by a lot. Modern lights can maintain over 1000 lumen quite effectively, there is rarely need for more brightness.

If I keep the room cold, would I get better performance out of the LED? Or would it have different effects on different parts of the housing, and it is a toss-up?

 

[Olumin]

If I keep the room cold, would I get better performance out of the LED? Or would it have different effects on different parts of the housing, and it is a toss-up?

Cooling helps a lot. How much cooling will help is depended on the lights ability to transfer heat energy, which is mostly dictated by the surface area of the head, then comes air flow and ambient temperature. Super bright LED power-throwers and flooders will sometimes have in-build fans combined with extensive cooling fins/ribs to help with heat dissipation.