Panasonic's New LED Bulbs Shine For 19 Years

Mike writes "As lighting manufacturers phase out the incandescent bulb, and CFLs look set to define the future of lighting, Panasonic recently unveiled a remarkable 60-watt household LED bulb that they claim can last up to 19 years (if used 5-1/2 hours a day). With a lifespan 40 times longer than their incandescent counterparts, Panasonic's new EverLed bulbs are the most efficient LEDs ever to be produced. They are set to debut in Japan on October 21st. Let's hope that as the technology is refined their significant cost barrier will drop — $40 still seems pretty pricey for a light bulb, even one that promises to save $23 a year in energy costs."

Comments

Not impressive lifetime for an LED

[mpoulton]

That's 38,143 hours. Not great for LEDs, actually. Most newer white LEDs are rated for 50k to 100k hours.

Re:Hope they put a capacitor in there

[paul248]

You really think Philips would try selling a half-wave rectified LED emitter for $40? That would be so unbelievably awful, you'd probably see return rates close to 100%.

Hell, even the LED Christmas lights I bought at Wal-mart last year are full-wave.

Re:Light bulb as a service

[EvanED]

till you break them and contaminate the room in mercury. Professional remediation is about $3000.

You forgot to finish your thought with "if you compeletely and unjustifiably overreact.

Re:ROI

[polar red]

I have only CFL's in my house. not one of them has broken since i moved in in june last year. 3 of those i brought with me from my previous house, which i have i used there for nearly 5 years.

Bad mathematics?

[Teun]

$40 still seems pretty pricey for a light bulb, even one that promises to save $23 a year in energy costs

You must be an accountant living on the outdated system of monthly and quarterly figures.
To have an amortisation within 2 years and outright profit for 17 years afterwards sounds like a pretty damn good investment.

Long life bulbs cost versus cost of replacement...

[sl149q]

I was talking to the facilities manager at the local University... about cost to replace bulbs in some of his buildings.. In some cases it is literally in the many tens of thousands of dollars range. They have to bring scaffolding in with a small crew to erect and move around. (Doors too small for a lift.)

He would be more than happy to pay $42/bulb IFF it meant he didn't have to go back in for two decades.

Re:ROI

[Firehed]

The bulb in TFA (I know, I know... but it wasn't in TFS) is rated 6.9w consumption, and is presumably the 60w-equivalent referenced in the summary. Most "60w" CFLs take around 12-15w if memory serves - so these LED bulbs are about twice as efficient. Save $23/yr for 19 years vs $12/yr for 5 years (you say 10, but they're usually rated to five and I've almost never seen one last more than two; they seem very sensitive to older wiring). It pays for itself in less than two years compared to an incandescent, and in four compared to a CFL.

Of course, that's all assuming they actually last that long. I don't doubt the power consumption ratings, but as I said I've never seen a CFL last anywhere near it's rated life. My understanding is that they have a limited number of starts due to the ignition ballast (which is external to the bulb in standard fluorescent tubes); I'd assume that if you have older wiring or other factors that may cause frequent power sags you'll burn through those starts unusually fast. That seems to be the case at my house, or would at least make some degree of sense to me. I could be dead wrong about the reasoning, but CFLs unquestionably die faster than incandescent bulbs around here. Hopefully this isn't an issue with LED bulbs.

Re:Light temperature

[rdebath]

This is because the really bright white LEDs are actually monochrome blue, they have a phosphor that converts some of that blue light into other colours, but not normally enough for a nice (sun like) colour.

There are other techniques that seem to convert the frequencies better; or they could use the old trick of putting different colour LEDs in one bulb. But for the moment if you want highest efficiency you're stuck with lots of blue in the light and a "cold" feel.

One point though, white LEDs are normally closer to the spectrum of the sun than incandescents, it's just that the blue spike is in the opposite direction to the very reduced blues you get from a incandescent. This is a known problem, so the conversions will continue to get better.

This is NOT informative, just plain wrong

[Kupfernigk]

Nobody would ever seriously run a production LED system like this. Typical forward voltage of white LEDs is around 3V. Supplying rectified AC would waste 97% of the energy on US 110V, thus making it less efficient that a halogen bulb and producing lots of heat in the resistor.

The things contain a switch mode power supply, like just about every small mains powered device nowadays. The SMPS converts input to a current output for LEDs, which is what they need for best efficiency. It does this on both halves of the AC cycle. This added complexity contributes to the cost, but not as much as you might think.

Early LED bulbs that ran off cheap transformers used for SELV lighting used series resistors, but the current is very variable and they are, basically, crap. They got away with it because big arrays of cheap LEDs were used. A long term solution really needs not more than two or three high power LEDs in an envelope, because this helps to drive down cost. But this requires an advanced power supply.

Re:This is NOT informative, just plain wrong

[smellsofbikes]

For what it's worth, my job is designing test hardware for LED drivers. As such I spend a lot of time taking apart other people's LED bulbs and seeing what they're doing. A scary number of current LED bulbs consist of a single diode, a big capacitor, and a string of LED's in series with their series forward voltage drop being roughly equal to 150 volts, and then a single current-limiting resistor at the end of the strand. That is the *worst* way I can think of to do the job. (Not to mention the cap they're using to smooth out the ripple is a very cheap electrolytic, with a lifetime of probably about 2000 hours if you're lucky, so that will be what fails.) The nicer low-end bulbs use a full wave bridge rectifier and sometimes even a linear regulator.

Of course, any good bulb worth buying uses an actual LED driver that acts as a constant current source. But even they still often use cheap electrolytics, meaning your LEDs will still have 95,000 hours of life in them when the bulb dies because the crappy caps they're using on the input and output sides of the switcher have failed.

If you're looking at a light and want to know generally what they're doing, see if you can count roughly how many LED's are in the fixture. If there are over 30, chances are it's a series string being run on rectified AC. If there are only a dozen or less, it's got a real driver and should at least give you reasonable efficiency, although no guarantees on lifetime. In an ideal world everyone would design LED drivers and use all ceramic or Nichicon caps, which have lifetimes measured in decades rather than months, but that'd cost a few pennies more and people will always buy the cheapest thing they can buy, particularly when you're working in a price range that's already an order of magnitude more expensive than the (incandescent) competition.