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The amazing progress of LEDs

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Re: The amazing progress of LEDs

#31

Post by joshuahedlund »

RoboTeddy wrote: post #4

One problem with current popular LED bulbs: They emit more blue light than incandescent bulbs [1]. If people light their households with LED lights at night, it might shift their circadian rhythms [2]. Screwed up circadian rhythms can have all sorts of negative health/productivity effects. [1] http://www.designingwithleds.com/measuring-light-quality-phi... [2] https://justgetflux.com/research.html

Interesting link. The contrarian in me says it only looks at a couple bulbs, and in my (limited) experience with a variety of new low-end LED bulbs the light quality varies greatly and has also been improving, so maybe this won't end up being much of an issue on circadian rhythms at all. But it's an interesting factor I hadn't been considering (how do LED's compare in this to the CFL's that have already replaced incandescents for many, I wonder?)

Re: The amazing progress of LEDs

#32

Post by jp555 »

RoboTeddy wrote: post #4

One problem with current popular LED bulbs: They emit more blue light than incandescent bulbs [1]. If people light their households with LED lights at night, it might shift their circadian rhythms [2]. Screwed up circadian rhythms can have all sorts of negative health/productivity effects. [1] http://www.designingwithleds.com/measuring-light-quality-phi... [2] https://justgetflux.com/research.html

Almost all the LEDs in my house are ~2700K, about the same an incandescent lights.

Regarding circadian rhythm, light from near-sleep-time television watching is much more of a concern, but that's been a problem for at least 30 years.

Re: The amazing progress of LEDs

#33

Post by tacoman »

jrapdx3 wrote: post #7
RoboTeddy wrote: post #4

One problem with current popular LED bulbs: They emit more blue light than incandescent bulbs [1]. If people light their households with LED lights at night, it might shift their circadian rhythms [2]. Screwed up circadian rhythms can have all sorts of negative health/productivity effects. [1] http://www.designingwithleds.com/measuring-light-quality-phi... [2] https://justgetflux.com/research.html

That thought occurred to me as well. Circadian phase delay already seems to be a problem re: the increasing brightness of our computing devices, almost all using LEDs. New phones, tablets, TV's, etc. should come with a warning to keep them "dimmed down" in the evening, or better, keep use to a minimum late in the day. Sure, I know, the odds are about zilch people would actually heed such advice, but it ought to be ou…

CRI (or at least what's advertised) has really improved in the last year. It not difficult to find 90+ bulbs at places like Home Depot.

Re: The amazing progress of LEDs

#34

Post by km3k »

jrapdx3 wrote: post #7
RoboTeddy wrote: post #4

One problem with current popular LED bulbs: They emit more blue light than incandescent bulbs [1]. If people light their households with LED lights at night, it might shift their circadian rhythms [2]. Screwed up circadian rhythms can have all sorts of negative health/productivity effects. [1] http://www.designingwithleds.com/measuring-light-quality-phi... [2] https://justgetflux.com/research.html

That thought occurred to me as well. Circadian phase delay already seems to be a problem re: the increasing brightness of our computing devices, almost all using LEDs. New phones, tablets, TV's, etc. should come with a warning to keep them "dimmed down" in the evening, or better, keep use to a minimum late in the day. Sure, I know, the odds are about zilch people would actually heed such advice, but it ought to be ou…

Yes, but there are solutions for brightness/color at least for our smartphones and PCs.

Android: https://play.google.com/store/apps/details?id=com.vito.lux&h...

PC: https://justgetflux.com/

Re: The amazing progress of LEDs

#35

Post by tacoman »

webignition wrote: post #15
seanalltogether wrote: post #5

I'm genuinely curious whether new homes will start wiring lighting for DC to accommodate all these new LED bulbs? I just don't have a good sense whether its more efficient to transform AC to DC at a central hub in the home to distribute to all rooms, or more efficient to do it at the bulb itself.

Interestingly, I'm looking to do exactly this in a new home (new to me, not newly constructed). I'll soon be moving to a park home (a relatively-permanent mobile home) that is in need of a fair amount of renovation. I'll be running all lighting, computers and the TV off 12v DV circuits powered by bank of vehicle batteries and where the batteries are charged from 12v solar panels.

What sort of plugs and connectors are you going to use for this?

Re: The amazing progress of LEDs

#36

Post by Someone1234 »

jp555 wrote: post #32
RoboTeddy wrote: post #4

One problem with current popular LED bulbs: They emit more blue light than incandescent bulbs [1]. If people light their households with LED lights at night, it might shift their circadian rhythms [2]. Screwed up circadian rhythms can have all sorts of negative health/productivity effects. [1] http://www.designingwithleds.com/measuring-light-quality-phi... [2] https://justgetflux.com/research.html

Almost all the LEDs in my house are ~2700K, about the same an incandescent lights. Regarding circadian rhythm, light from near-sleep-time television watching is much more of a concern, but that's been a problem for at least 30 years.

I'd pay good money for a TV with integrated F.lux (i.e. blue gradually degrades with the movement of the sun).

I started using F.lux too many years ago now to count, and honestly it really seemed to help. However getting similar kind of functionality on all of your other devices (e.g. Tablets, Phones, TV, etc) is near impossible right now.

As far as I know the "blue light ruins sleep" research is fairly decent, so hopefully it isn't a placebo.

Re: The amazing progress of LEDs

#37

Post by webignition »

ZoFreX wrote: post #27
webignition wrote: post #15

Earlier quoted context omitted.

Interestingly, I'm looking to do exactly this in a new home (new to me, not newly constructed). I'll soon be moving to a park home (a relatively-permanent mobile home) that is in need of a fair amount of renovation. I'll be running all lighting, computers and the TV off 12v DV circuits powered by bank of vehicle batteries and where the batteries are charged from 12v solar panels.

Converting voltages is trivial with AC, how do you handle devices that require something other than 12v (lots of phones want 5, lots of laptops want 18) with a DC system?

I'll be fitting some 12v-based USB wall sockets, much like the type you can fit in a car. These can then provide power for phones.

Regarding computers, I've so far only considered my desktop. You can get ready made DC to DC ATX power supplies quite easily [1].

[1] http://www.mini-box.com/DC-DC

Re: The amazing progress of LEDs

#38

Post by webignition »

tacoman wrote: post #35
webignition wrote: post #15

Earlier quoted context omitted.

Interestingly, I'm looking to do exactly this in a new home (new to me, not newly constructed). I'll soon be moving to a park home (a relatively-permanent mobile home) that is in need of a fair amount of renovation. I'll be running all lighting, computers and the TV off 12v DV circuits powered by bank of vehicle batteries and where the batteries are charged from 12v solar panels.

What sort of plugs and connectors are you going to use for this?

Could you be a little more specific?

Re: The amazing progress of LEDs

#39

Post by poopchute »

Someone1234 wrote: post #36
jp555 wrote: post #32

Earlier quoted context omitted.

Almost all the LEDs in my house are ~2700K, about the same an incandescent lights. Regarding circadian rhythm, light from near-sleep-time television watching is much more of a concern, but that's been a problem for at least 30 years.

I'd pay good money for a TV with integrated F.lux (i.e. blue gradually degrades with the movement of the sun). I started using F.lux too many years ago now to count, and honestly it really seemed to help. However getting similar kind of functionality on all of your other devices (e.g. Tablets, Phones, TV, etc) is near impossible right now. As far as I know the "blue light ruins sleep" research is fairly decent, so ho…

For Android I use something called "Twilight". It is a good stand in for F.lux, and even has a few extras. For time control, it has the standard sunrise/sunset coordinate system that F.lux uses, as well as Alarm control to set custom bedtime/wakeup.

Re: The amazing progress of LEDs

#40

Post by zAy0LfpBZLC8mAC »

webignition wrote: post #24
crististm wrote: post #18

Earlier quoted context omitted.

Have you considered cabling loses? There is a reason power lines use very high voltages.

I've considered voltage drop over cable length only in as far as I'm aware that it occurs. I haven't tested the level of voltage drop. I currently use 12v circuits in my camper van and haven't experienced any significant drop over cables about 3m in length. LED-based lighting and a 12v fridge operate as expected and the voltage at the point the power reaches these devices is very close to the voltage over the battery…

Just to be sure: You are aware that you have to measure the voltage drop under load? Even with rather thick wires, 20m should give you some noticable voltage drop with any non-minimal load.
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