[MD]

We've all lived through the switch from incandescent to CFL and now LED technology. I haven't tallied the energy savings but given the following facts, the global impact should be significant.

-CFL provides three times the lumens (light "volume" per watt) than incandescent.
-LED's are marginally better than that.
-There are BILLIONS of light bulbs glowing around the planet that are being rapidly switched over.
-Manufacturing costs (energy in) for CFL/LED are fast reaching parity with incandescent.

Energy efficiency = opportunity, now and long into the future. The math is simple.

[dolanbaker]

Unfortunately, it's not as simple as that, it appears that as the lights are more efficient more are being used to illuminate the areas than previously. Still a saving but not as great a saving as would have been made in a like for like substitution.

[MD]

Unfortunately, it's not as simple as that, it appears that as the lights are more efficient more are being used to illuminate the areas than previously. Still a saving but not as great a saving as would have been made in a like for like substitution.

Jevon's paradox comes into play, of course, but at the moment the savings are out running new applications, which is expected given a constrained energy supply.

There is a simple economic principle being played out in the energy sector these days. It's called "diminishing returns".

Peak Oil, in other words.

Such a simple yet amazingly abused concept.

[yellowcanoe]

I'm waiting to see how effective the ban on 75 watt and 100 watt incandescent bulbs in Canada that took effect on January 1 will be. The sale of bulbs manufactured before January 1 is allowed so it is possible that distributors stocked up to cater to the pro-incandescent crowd. We did rush out to buy some 100 watt incandescent bulbs to ensure that our 40 year old Easi-Bake oven remains usable!

I do not agree that CFL bulbs should be classified as toxic waste. The amount of mercury they contain is quite minute and even if one of these bulbs breaks in your house I don't think it is something you need to freak out over. Telling people that the bulbs are toxic and cannot be discarded in regular garbage just gives people another excuse to continue using inefficient incandescent bulbs.

[dolanbaker]

We have a Calif. residential requirement on new construction for CFL's in the bathroom/kitchen. It helps I guess? A downside: the fixtures include the ballast and the sockets are double-pin (rather than screw-in) so I don't know if I can convert to LED when they are available, without changing the ballast, if that is even possible?

Where's the national carbon tax?

That sounds like a fairly short-sighted law, in a few years it may well be the case that LED bulbs completely outperform CFL's in the future with builders forced into installing lamps that householders don't want.

[Surf]

dolanbaker wrote:
pstarr wrote:
We have a Calif. residential requirement on new construction for CFL's in the bathroom/kitchen. It helps I guess? A downside: the fixtures include the ballast and the sockets are double-pin (rather than screw-in) so I don't know if I can convert to LED when they are available, without changing the ballast, if that is even possible?

Where's the national carbon tax?
That sounds like a fairly short-sighted law, in a few years it may well be the case that LED bulbs completely outperform CFL's in the future with builders forced into installing lamps that householders don't want.

I live in california and My understanding is that the law does not require a spacific type of pulb. You can meet the requirement with CFL, LED, or room ocupancy sensors that automatically turn off the lites when you leave.

Sylvnia, Phillups and other major manufactures now make LED and CFL that fit conventional light fixtures. I just installed 3 Sylvania LED bulbs that fit light fixtures designed for Par 30 bulbs. So there is no need to buy speical fixtures.

dolanbaker wrote:
Unfortunately, it's not as simple as that, it appears that as the lights are more efficient more are being used to illuminate the areas than previously. Still a saving but not as great a saving as would have been made in a like for like substitution.

Jevon's paradox comes into play, of course, but at the moment the savings are out running new applications, which is expected given a constrained energy supply.

The previous owner of my home was using about 300W of power to light the main living area. When I moved in I put in track lighting and used CFLs when possible. Today it is almost all LED, I am using about 1/3 the power for more light and there are few dark areas of the room.

Yes I could put in 300W of LED lighting but why would I want to wear sunglasses inside?

[careinke]

We have a Calif. residential requirement on new construction for CFL's in the bathroom/kitchen. It helps I guess? A downside: the fixtures include the ballast and the sockets are double-pin (rather than screw-in) so I don't know if I can convert to LED when they are available, without changing the ballast, if that is even possible?

Where's the national carbon tax?

Am I missing something? I didn't know you used ballast with LED's. I like the new LED bulbs, they put out a lot less heat than CFL's, use even less power, have no warm up times like CFL's, and last virtually forever.

As my CFL's burn out, I'm replacing them with LED's.

[dolanbaker]

I expect that there will soon be a new standard for LED installations that will include a low voltage lighting circuit and a central inverter for the whole house and standardized connectors.

It just needs a few more years for the standard to evolve.

[Surf]

dolanbaker wrote:
I expect that there will soon be a new standard for LED installations that will include a low voltage lighting circuit and a central inverter for the whole house and standardized connectors.

It just needs a few more years for the standard to evolve.interesting. like current low-voltage ac lighting with a central transformer and small guage wire

If you reduce the voltage you must increase the current to deliver the same power. If you increase the current you must increase use thicker wire. If you don't use thicker wire will run hot and more power will be converted to heat before it gets to the light. Thicker wire and the transformer and the specal low voltage connectors add expens and offer no real beifit over 120VAC fixtures.

[Loki]

Unfortunately, it's not as simple as that, it appears that as the lights are more efficient more are being used to illuminate the areas than previously. Still a saving but not as great a saving as would have been made in a like for like substitution.

There's always going to be a rebound effect for energy efficiency measures, but it's usually only in the 10-20% range.

As for LEDs, I'm happy with the ones I use, bright warm light that uses minimal electricity. I think they'll be a positive development and will play a useful role in reducing electricity demand (or at least reducing growth of demand). Much better than CFLs as far as I'm concerned.

[Loki]

Thicker wire and the transformer and the specal low voltage connectors add expens and offer no real beifit over 120VAC fixtures.

Yeah, I'm not convinced there be any benefit of 12V lighting in a grid-tied home, I'd need to see the numbers. 120V allows the use of much smaller gauge wires, and the juice coming into the home is already 120V. You'd need a converter to step the voltage down, which will have inefficiencies that could eliminate any efficiency associated with 12V lights.

12V definitely makes sense for off-grid applications, though. I'm still using an inverter and 120V LED lamp for my main lighting, but I plan on experimenting with 12V lighting. Just need too get some 1141 LED bulbs. These bulbs will allegedly produce 280 lumens of warm light using 0.18 amps. The AC lamp with 7W LED I'm currently using produces a rated 450 lumens using 0.58 amps, not including inverter draw (0.27 amps).

So in theory 12V lights will produce the same number of lumens as my current set up using 50% of the amps, plus I may be able to keep my inverter off most of the time. I have a very small battery bank, this will help to limit how often I have to recharge it. The run between the battery bank and the lights is quite short, so wire sizing shouldn't be a problem.

[Keith_McClary]

I expect that there will soon be a new standard for LED installations that will include a low voltage lighting circuit and a central inverter for the whole house and standardized connectors.

It just needs a few more years for the standard to evolve.

interesting. like current low-voltage ac lighting with a central transformer and small guage wire

LEDs are not like incandescents which can be wired in parallel at the appropriate voltage. Each LED requires a current regulator circuit board. When they run on household voltage the circuit board built into the bulb includes the inverter (and reduces the voltage). I doubt whether a central low voltage DC system would be better in cost and energy efficiency.

[Surf]

12V definitely makes sense for off-grid applications, though. I'm still using an inverter and 120V LED lamp for my main lighting, but I plan on experimenting with 12V lighting. Just need too get some 1141 LED bulbs. These bulbs will allegedly produce 280 lumens of warm light using 0.18 amps. The AC lamp with 7W LED I'm currently using produces a rated 450 lumens using 0.58 amps, not including inverter draw (0.27 amps).

There are a lot of 12V halogen lamp fixtures available for homes, and there are companies making LED bulbs that use the 12V halogen G4 or G9 bipin base. The bulb you linked to is for for cars. You would have to make your own lamp fixtures or modify home lamp fixtures. Anid if the manufacture of the pulb you linked to stopped manufacturing them you would not have spares. there is a much larger market for for 12V G4 bipin LED bulbs which are compatable with all current 12V halogen lamp fixtures.

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LEDs are not like incandescents which can be wired in parallel at the appropriate voltage. Each LED requires a current regulator circuit board. When they run on household voltage the circuit board built into the bulb includes the inverter (and reduces the voltage). I doubt whether a central low voltage DC system would be better in cost and energy efficiency.

Not quite true. The minimum needed is a constant voltage source and a resister with the LEDs in series, parallel, or occasionally a series/parallel configuration. Constant voltage source have been used with LEDs for decades and are very reliable. The key is to insure the leds all have the same voltage requirement and that they operate at a stable temperature. Constant current power sources are a little more efficient and and can compensate for changes in power demand that accompany LEDs running at high temperatures.

I have built a LED plant grow lamp with leds wired in a series parallel configuration and it is powered by a 12V power supply and some small resisters. With a 40W power consumption it is painful to look at directly and has no heat sinks and no fans. The key for this type of assembly is to insure that the leds operate at a reasonable and stable temperature. My grow lamp operates at a temperature of about 100F which is well below 130C temperature limit sepecified by many LED manufactures.

[careinke]

I have built a LED plant grow lamp with leds wired in a series parallel configuration and it is powered by a 12V power supply and some small resisters. With a 40W power consumption it is painful to look at directly and has no heat sinks and no fans. The key for this type of assembly is to insure that the leds operate at a reasonable and stable temperature. My grow lamp operates at a temperature of about 100F which is well below 130C temperature limit sepecified by many LED manufactures.

Interesting, how well does your grow lamp work? Would you do it again, or is the payoff too small for the effort? Did you have plans for its construction, or did you design it yourself? Do you happen to know the light spectrum it emits?

Sorry for all the questions, but it sounds like a nice project.

Thanks,
Cliff