The year of the led bulb. Coming into it's own.

I know this is nothing new but it just amazes me how many new decent led bulb products have made their way into box retail stores in the past year or so.

I haven't stepped into the lighting isle of a store like a Home Depot or a Lowes for over a year at least until today. Of course I myself have had led bulbs and high power led flashlights for years, but it's really different in stores this year than even last year in my opinion. The price of good bulbs is still pretty high, but I was just amazed at how big the led bulb section and advertising is.

It just really makes me happy as not only do I see the market growing, but also the prices coming down significantly in coming years while the quality and output of good led bulbs goes up. What does everyone else think about this. Is the led bulb truly starting to "happen" in a big way finally.

EDIT: I did buy two of the most recent Cree 2700k 800lm soft white high cri bulbs. However I'm noticing how little heat sinking there really is on so many of the current bulbs out there. I understand so many have to fit enclosures, but I also wonder if it's a marketing thing. People want led bulbs that look very similar to older bulbs. The result is tiny heatsinks or basically no heatsinks or fins at the base of bulbs putting out 800 or even 1000-1600 lumens. That's crazy. Sure it might be tested to not catch on fire, but so much for the super long led life span. Those things will surely fry or at least lose brightness a lot faster than led's should. Surely they will be great for years, but it's just something that's very noticeable considering how much heat these bulbs really put out.

EDIT 2: I pulled one of the 800 lm bulbs with base fins out of an open top wall light after a few hours running. The top glass dome of course is not really hot at all, but the fins were literally way to hot to touch against the skin for more than a fraction of a second without causing severe skin burning. That kind of heat is surely not good for the leds over the long term.

The transition to LED has been very apparent at the trade shows like LightFair too. A few years ago LED was mixed in with everything else but now it basically dominates the show. The challenge is to be innovative, high quality, and reasonably priced.

It's really difficult to assess the anticipated lifetime of an LED based product by judging the temperature of the heat sink fins (as a generalization). My understanding is that if the heat sink isn't hot it's either way oversized or simply isn't transferring heat very well. The only way to know for sure if the product will last will be to measure the LED junction temperature. Getting it right takes real effort, skill and engineering. I rarely do consumer product heat sinks! I can make it look pretty and I run a basic surface area requirement calculator but doing it right takes a robust model, good software and the knowledge to run it. The A19 retrofit is a challenge getting the omnidirectional output within the size constraints and aesthetic "requirements". It's easy until you have to cram a power supply in there. Imagine the challenge of the 100W replacements!

I haven't checked in a while (but I will and will correct this if I'm wrong) but I think that EnergyStar requires an L70 of 10,000 hours for an A19 replacement. LEDs will last longer but in this application they don't have to even though many bulbs have an estimated 25,000 hour lifetime or more. I had always asked why we were over designing LED bulbs to last 50,000+ hours when it would drive the price so much higher. A smaller heat sink, fewer LEDs driven harder or more mid-range LEDs crammed in will lower the price and shorten the lifetime of the bulb but it will still meet spec. Personally I would buy a 5000 hour bulb if the price were the same as a halogen equivalent.

martinaee said:

EDIT 2: I pulled one of the 800 lm bulbs with base fins out of an open top wall light after a few hours running. The top glass dome of course is not really hot at all, but the fins were literally way to hot to touch against the skin for more than a fraction of a second without causing severe skin burning. That kind of heat is surely not good for the leds over the long term.

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I don't disagree about trapped heat being bad for LEDs, but remember that if the heatsink on the outside is really hot,
that means that the heat on the inside is getting released to the outside environment.

Oh yeah. I'm very well aware of that. But with how careful it seems high end flashlight makers are about heat to led's it's obvious compromises are having to be made to push high power led tech into a well established form factor.

Of course heat sinks are meant to get hot, but when a heat sink is getting hot enough that you literally can't touch it for more than a split second without burning yourself you know that heat isn't necessarily escaping fast enough from around the emitters and the emitter themselves. The heat will dissipate faster through skin touch than non-moving air so it's not like these bulbs are exactly throwing off the heat at a high rate. These aren't flashlights either where use outdoors helps dissipate heat due to general air flow. I feel that purpose built bulbs that don't conform to preexisting form factor standards would be MUCH better if they had much bigger heat sinks. I'm sure the manufacturers know this though, but they also know they need to make something familiar looking in order to get the market to buy them en masse.

I've been using 800lm led bulbs now and they are either not enclosed at all or enclosed only from the sides with air still able to come from the top and bottom. There is no way I could see these in an overhead fixture without overheating or seriously reducing the life of the bulb... which is what these still very expensive bulbs are meant to do.

From what I've read heat can also change the hue of the bulbs/emitters over time so when these bulbs start turning casting pinkish hues people aren't going to be happy.

It's not that big a deal I know. The benefits of these new led bulbs are amazing and I love them, but just see that there is so much more that could be done with them once people accept that they don't have to look a certain way anymore. It's getting there--- there have already been some crazy designs put out recently.

Well, the copper is good to about 500C, the solder to about 200C, and the LED to 150C. The weak point will be:

1. Capacitor failure. This is the real monster under the LED Lighting bed. Cree probably knows better than to set landmines in the LED Lighting business - That will be their bread & butter for the next few decades. They'll use top-shelf, hot-rated capacitors.
2. Long-term phosphor & diode degradation. This is reasonably-well explored by now.


I have some machinery at work that runs in the heat. Thermocouples, steam valves, etc all are made to operate in very hot environments. It just costs more money. If you put the money into a good driver, and adequate thermal design (The capacitors will be the weak point), then you have a long-lasting LED light. I have a better warm-fuzzy feeling about my DIY lights that don't get 5C over ambient, but then I don't have the same cost vs. risk that Cree does (Adding the fan costs me $5, adding a fan costs Cree $1 x ten million units).

I disagree. LED lighting is still a mess. At our local HD's, there is a dizzying array of LED bulbs I don't need. On other aisles or endcaps, they have the casualties of unsold, outdated LED bulbs, still not marked down enough to be interesting.

Our house, and most homes I know of use 6" cans. Ours uses Lightolier cans, which are not compatible with the HALO type spring loaded retrofits. And I can never find a decently priced BR40 bulb. We use the CREE 47 degree PAR38 floods in a few areas, but mainly continue using incan BR40/PAR38's.

Another issue I have is the CRI. I WILL agree with you only when there are more high CRI options. It is very limited right now. I see Costco has FEIT high CRI, but FEIT gets a bad rep on quality. Almost all retail LED lighting is 80ish CRI. And I won't even open the can of worms about CCT. Myself, I do like 2700K in the home and 4000K in the utility areas, but 2700K at 80 CRI is a let down.

Another problem I see is that designs keep changing. If, in the near future you need to relamp just one of your LEDs, likely you won't find a similar product. In an open fixture it'll be an obvious mismatch.

The heatsink thing....leave that up to the manufacturer. What do you know about the heatsinking needs of their product anyway? Yes, heatsinking makes sense, but does their particular design actually warrant it (at least in the manner that you expect to see)?

As far as I am concerned, the LED market is a mess. Designs keep changing, CRI has been low for a while now, quality is hit or miss, pricing is all over the map.

Stable pricing, better high CRI options, and product designs that have longer shelf life will signal, for me, when the LED bulb comes into it's own.

made in china said:

...Our house, and most homes I know of use 6" cans. Ours uses Lightolier cans, which are not compatible with the HALO type spring loaded retrofits. And I can never find a decently priced BR40 bulb. We use the CREE 47 degree PAR38 floods in a few areas, but mainly continue using incan BR40/PAR38's....

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I was at (Mountain View, Cal) Costco yesterday and they had Feit BR40s for $11.98/each! They also had Feits integrated 5"-6" can retrofit, with claimed CRI of 94, for $13.98. Unfortunately for me, when I replace my incandescent BR40s, I am holding out for 3000-3500K. Even at these prices, we don't use our BR40s enough to justify replacing them on energy usage just yet.

Our local Home Depot has about doubled the amount of shelf space for LEDs in the last month or two. And that is not even counting all the LED fixtures in the Lighting department, various end caps, and cardboard floor displays.

made in china said:

I disagree. LED lighting is still a mess. At our local HD's, there is a dizzying array of LED bulbs I don't need. On other aisles or endcaps, they have the casualties of unsold, outdated LED bulbs, still not marked down enough to be interesting.

Our house, and most homes I know of use 6" cans. Ours uses Lightolier cans, which are not compatible with the HALO type spring loaded retrofits. And I can never find a decently priced BR40 bulb. We use the CREE 47 degree PAR38 floods in a few areas, but mainly continue using incan BR40/PAR38's.

Another issue I have is the CRI. I WILL agree with you only when there are more high CRI options. It is very limited right now. I see Costco has FEIT high CRI, but FEIT gets a bad rep on quality. Almost all retail LED lighting is 80ish CRI. And I won't even open the can of worms about CCT. Myself, I do like 2700K in the home and 4000K in the utility areas, but 2700K at 80 CRI is a let down.

Another problem I see is that designs keep changing. If, in the near future you need to relamp just one of your LEDs, likely you won't find a similar product. In an open fixture it'll be an obvious mismatch.

The heatsink thing....leave that up to the manufacturer. What do you know about the heatsinking needs of their product anyway? Yes, heatsinking makes sense, but does their particular design actually warrant it (at least in the manner that you expect to see)?

As far as I am concerned, the LED market is a mess. Designs keep changing, CRI has been low for a while now, quality is hit or miss, pricing is all over the map.

Stable pricing, better high CRI options, and product designs that have longer shelf life will signal, for me, when the LED bulb comes into it's own.

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Yeah I totally agree. What I generally mean is that it's amazing to me how much bigger LED is as a category in the public eye now, due to being pushed and prices coming down considerably (but not enough). Consistency and better variety of color temps and high cri are definitely needed still though.

Yeah, it is amazing how much LED product is available nowadays. I won't be sad to see CFL's go away.