The GOOD LED Light Bulb thread

[Gumby]

Quote:

Originally Posted by target2019 $54.97 at the homedepot? OMG!!!

At my Home Depot, that is the price for a two-pack. Still expensive, but not as bad as you think.

[travelover]

Quote:

Originally Posted by MRG Isn't that the British standard? Or is this a Brit living elsewhere? MRG

Do you feel a tug on your leg?

[NW-Bound]

An electric shock at 110V is nothing compared to 220V!

Been there, done that...

[Animorph]

Quote:

Originally Posted by walkinwood I've been thinking for some time, that our 110V house wiring is obsolete. We should have 12V DC supply everywhere alongside the 110V. In our living room, bedroom & office/dens - there really is no need for 110V any more.

All you have to do is wire your house with outdoor Malibu lights. The systems exist at least. I think some track lights also use a remote 12v supply.

[MRG]

Quote:

Originally Posted by travelover Do you feel a tug on your leg?

Guess so. Well I've bit on sillier things:-)

MRG

[walkinwood]

The detailed knowledge available on this forum on just about any topic always amazes me.

[NW-Bound]

I do not know about this DC thing. It's far better to keep the AC, even at 110V instead of going to 220V. Other countries use a higher voltage to reduce copper wiring cost. We are rich, we don't care!

However, going from 60Hz to 400Hz like aircraft power makes sense, don't you think?

Transformers are smaller, and motors run better, although more motors are now are of the brushless DC types.

Even power supplies inside modern electronics get better with smaller capacitors, which also applies to the power supplies for the brushless motors already mentioned.

[travelover]

Quote:

Originally Posted by NW-Bound ........However, going from 60Hz to 400Hz like aircraft power makes sense, don't you think? ........

If we went to 400 Hz, I don't know if this old wiring could keep up that pace.

[TOOLMAN]

Quote:

Originally Posted by walkinwood The detailed knowledge available on this forum on just about any topic always amazes me.

After following this thread, I went to HD and bought a few LED bulbs. They had a $5 off sale.

Then I got to thinking... my house is all electric, and an incandescent bulb produces 95% heat, so I might as well use up those cheaper incandescent bulbs in the winter months. I'll save the LED for the summer.

If and when I get to an age when I start considering not buying green bananas, I think a 20 year LED bulb will be a hard sell. :-)

[explanade]

Well the good thing is LEDs are so much more power efficient.

Four of them for a moderate sized room uses less than 40 watts (even less with a dimmer) and is as bright as a couple of 75 watt incandescents, maybe brighter.

[explanade]

Quote:

Originally Posted by TOOLMAN After following this thread, I went to HD and bought a few LED bulbs. They had a $5 off sale. Then I got to thinking... my house is all electric, and an incandescent bulb produces 95% heat, so I might as well use up those cheaper incandescent bulbs in the winter months. I'll save the LED for the summer. If and when I get to an age when I start considering not buying green bananas, I think a 20 year LED bulb will be a hard sell. :-)

But bulbs are not the most efficient way to heat your house. You're using more electricity to reach a given level of brightness.

Plus those LEDs are suppose to last as long as 20 years so you're not saving much out of their life by waiting a few months.


With $5 off the cheapest LED bulb was $5?

[travelover]

Quote:

Originally Posted by TOOLMAN ........ my house is all electric, and an incandescent bulb produces 95% heat, so I might as well use up those cheaper incandescent bulbs in the winter months. ..........

Is your house heated with resistance heating or a heat pump? There is a big difference in efficiency. An incandescent bulb is just a resistance heater.

[calmloki]

OT here, but CostlyCo has 4 packs of little bitty 60W equivalent CFLs, 2700K color (warm color rather than hard white) for $4.99 with a $2 discount applied at the register. $3/pack? $0.75/bulb? After buying 25 4-packs of incandescents @ $1.28 I splurged on 15 packs of the CFLs. At about twice the price of the cheapest resistance bulbs they make sense, burning 1/4 of the juice and liable to last at least twice as long, if not the vaunted 10,000 hours marketing claims....

I now return you to discussion of the bulbs that cost, at best, more than six times that amount and burn the same amount of juice as the CFLs.

[TOOLMAN]

Quote:

Originally Posted by travelover Is your house heated with resistance heating or a heat pump? There is a big difference in efficiency. An incandescent bulb is just a resistance heater.

I have a heat storage system. I noticed they were popular in Europe, so when I built my house I imported them.
Basically it heats up a box or rocks during off peak rates then it releases the heat during on peak.

[travelover]

Quote:

Originally Posted by TOOLMAN I have a heat storage system. I noticed they were popular in Europe, so when I built my house I imported them. Basically it heats up a box of rocks during off peak rates then it releases the heat during on peak.

OK, so this is resistance heating with a twist. The heat from the light bulbs would be paid for at the rate in force when you needed the light.

[travelover]

Quote:

Originally Posted by calmloki .........I now return you to discussion of the bulbs that cost, at best, more than six times that amount and burn the same amount of juice as the CFLs.

Are you saying that LEDs have the same efficiency as CFLs? I don't think so.

Compare: LED Lights vs CFL vs Incandescent Lighting Chart

[TOOLMAN]

Quote:

Originally Posted by travelover OK, so this is resistance heating with a twist. The heat from the light bulbs would be paid for at the rate in force when you needed the light.

Makes sense. BTW the heat storage is 220v and saved us about 2k per year for the last 20 years vs resistance heating alone.

[travelover]

Quote:

Originally Posted by TOOLMAN Makes sense. BTW the heat storage is 220v and saved us about 2k per year for the last 20 years vs resistance heating alone.

I believe it, electrical resistance heating is about the most expensive way to heat.

[calmloki]

Quote:

Originally Posted by travelover Are you saying that LEDs have the same efficiency as CFLs? I don't think so. Compare: LED Lights vs CFL vs Incandescent Lighting Chart

The equivalent LEDs I've looked at are pretty close in electric consumption to the CFLs.
For instance:
Cree 13.5W TW Series Soft White LED Bulb - Smart home - CNET Reviews

Or the first LED in this thread:

Home Depot Ecosmart 9 Watt (65W) BR30 Soft White (2700K) LED Flood Light Bulb
650 Lumen, Life 22.8 years based on 3 hrs./day
SKU184-441, UPC 887437000694, $15.88 and still the same price today in HD stores

The FEIT CFLs I referenced from Costco:
13W 900 Lumen, average life 10,000 hours (@ 3 hours/day = 9.1 years) 2700K, advertised as RoHS compliant, contrary to your chart's assertion on CFLs. $0.75/bulb

So the Ecosmart LED puts out 72% of the lumens but only uses 69% of the energy and lasts 2.5 times as long? But costs 21 times as much?

If instant on is really important and your bulbs are not at risk and they are located in really awkward locations for changing and you believe the LED lifespan claims then by all means have at 'em.

I'll defer to Fermion's comment early in the thread:

Not that it probably makes a difference or many of you care, but it is the electronics that are failing in the LED bulbs, not the LED element itself. I opened up 7 failed bulbs and found the LED elements to be perfectly fine. They are wired as a series string of about 12 LEDs per string...sometimes two parallel strings of 12 LEDs. It takes about 22 volts for most of these to get to the knee in the diode conduction curve and they run on around 36V DC.

The buck converter which takes in 115VAC and outputs the 36V DC uses things like capacitors with a 1000 hour or 2000 hour typical life for rated spec (and this is usually for moderate temperatures...shorter life at higher temps). All of the units were potted and I was too lazy to try and dig out the potting to figure out exactly what failed, but I am guessing it was these capacitors degrading, causing some sort of change in the buck converter. This either blew the converter chip or perhaps popped a non-resettable fuse in the lamp guts.

Sorry if this was TMI. I love the LED lights but I buy them expecting only to get 2000 to 3000 hours out of them. I am going to make a huge 5000 watt LED spotlight someday out of all of these broken elements.

[samclem]

Quote:

Originally Posted by TOOLMAN I have a heat storage system. I noticed they were popular in Europe, so when I built my house I imported them. Basically it heats up a box or rocks during off peak rates then it releases the heat during on peak.

I recall reading about a system some guy had rigged up that used the waste heat from his AC unit to heat a >big< bin of rocks or water drums. The bin was under the house and well insulated. The bin of stuff got warmer and warmer thoughout the summer as the AC ran. Other waste heat (from clothes drying, etc) could also be added to the bin. In the winter, he extracted heat from it.
Seemed like a good idea in principle, but the payback period would likely be awfully long. It might be practical for a superinsulated home. With many of these schemes (earth tubes, etc) the trick is to control moisture and to avoid the growth of nasty molds and organisms inside the storage media.