5 ms·

Why the falling cost of light matters (2017)

27 points by okket 8y ago

Double_a_92 8y ago
Nice try Mr. Moth.
sydd 8y ago
Sadly there are a lots of flaws of LEDs, I think they are put in the spotlight a bit too early. While they are a lot better than previous light saving technologies (like CFLs which took a minute or two to warm up), most of the bulbs in the market currently have lots of drawbacks: - Their CRI is pretty low, around 80. - They flicker causing eye strain. There are now LEDs that solve both, its just a pain to find them (and cost 2-10x more than other LEDs.)
- iainmerrick 8y ago
  How do you go about finding high-quality LEDs? Are they easily available in standard bulbs?
  - toss1 8y ago
    Just tinkering, I've found several factors are important. First is the color temp and CRI of the bulb/chip; make sure they match your application. Sometimes mixing bulbs/chips works well to get a more pleasing & usable spectrum. I've also found that the strip LEDs with multiple colors and a tunable controller produce good results. Second, find a power supply/controller that has a very high frequency. LED's don't inherently flicker, and when powered straight from a source like a battery provide a completely steady light. The flicker is typically from a time-chopping brightness controller. Cheap ones may use 60Hz, which the eye can still see, especially in the peripheral vision areas (rod cells, sensing only grays detect motion much better, whereas color-sensing cone cells at the center of the visual field have a slower response so detect flicker less well). Ideally, get a controller well above 25KHz to also eliminate any audio artifacts. I'd very much like to see someone more expert chime in!
    - iainmerrick 8y ago
      Are there any dimmable LED strips that operate by fully illuminating X% of the LEDs? As opposed to time-slicing all the LEDs. I don’t know enough about hardware to know if that would be feasible. The flickering and whining is pretty bad in all the dimmable LED bulbs I’ve used (but I haven’t yet looked hard for high-end ones).
      - dbuder 8y ago
        For long life, LEDs need to be off some of the time, better to run at 20mA 50% of the time than 10mA 100% of the time. That always on warning light on your cheap electronics runs at low power and has a relatively high failure rate. You need to tune or shield the drive to avoid troublesome EMI.
      - thatcat 8y ago
        Yea, my desk lamp does that.
      - OnlineCourage 8y ago
        That severly shortens the lifetime of an LED, like by a factor of 10. So I would guess it is not common because much of the benefit that gets marketed is the longer lifetime. It is possible to build a better dimmer switch which actually works across the full profile of voltage variation but the problem then is you have to pay an engineer money and why do that when you can spend money on booze and dinners to win more sales contracts with your lighting distributors and get a higher ROI? The lighting world is a very consolidated place.
  - lotsofpulp 8y ago
    I haven't had any problems with the GE Classic LEDs: https://www.lowes.com/search?searchTerm=ge+classic+led https://www.lowes.com/search?searchTerm=ge+classic+led
    - sydd 8y ago
      Sorry, they are likely crap. If there is no Ra/CRI value given its 80.
  - sydd 8y ago
    Yes. Just google for stuff like 95 CRI or high CRI bulbs. They are a bit more expensive than normal bulbs though. Some examples of good ones: https://www.waveformlighting.com/home-residential https://www.waveformlighting.com/home-residential https://www.mueller-licht.de/ https://www.mueller-licht.de/ And surprisingly IKEA Ledare bulbs are pretty good too (although not as good as the ones above)
- JohnJamesRambo 8y ago
  The cheap LED light bulbs I get at Walmart seem just fine. Have you bought them recently? I don't notice any flicker and their light renders colors better than my incandescents or CFLs ever did. They grow plants the best too, in my head to head tests.
- OnlineCourage 8y ago
  LEDs do not flicker, it is the pulse width modulation within the control circuit which causes flicker, which ultimately is due to poor design not the LED itself. CRI is based upon the patents held by the semiconductor fab which affect the type of semiconductor which can be used and how the phosphor is applied which varies. Binning (or statistical sampling) of LED chromacity improves over time across the industry. LEDs work great as spotlights actually because the most widely available lens material creates a sharp, direct light as opposed to a diffuse light. ;-)
- lozaning 8y ago
  Do they have LEDs now that only put out light in a small spectrum of filterable wavelengths? The city of Tucson for a long time resisted swapping all their street lights out from the existing sodium lights because local astronomers found it significantly harder to filter out the wide gamut of "junk light" from LEDs.
fabricexpert 8y ago
> Switch off a light bulb for an hour and you are saving illumination that would have cost our ancestors all week to create > But the price of light alone tells a fascinating story: it has fallen by a factor of 500,000, far faster than official inflation statistics suggest. This is a fantastic anecdote in favour of automation, technology, science and research. I can imagine how the sperm whale sailors, candle stick makers and matchbox makers felt when the light bulb started to become commonplace and replace their jobs. We will see the same arguments against progress coming through again and again over the next 100 years, I hope we continue to prevail in our growth and find a solution for those displaced when technology overtakes their job.
- vwcx 8y ago
  > I can imagine how the sperm whale sailors, candle stick makers and matchbox makers felt when the light bulb started to become commonplace and replace their jobs. And now the match industry has an upper-end, boutique product for wealthy millennials. Markets in everything. http://skeemshop.com/apothecary-match-bottles/ http://skeemshop.com/apothecary-match-bottles/
  - nkrisc 8y ago
    Huge, dim "Edison" bulbs also appear to be trendy. The cycle seems to be accelerating.
- henvic 8y ago
  You are probably familiar with... but for those who aren't... Here is something cool to read by Frédéric Bastiat, a French philosopher during the 19 century: http://bastiat.org/en/petition.html http://bastiat.org/en/petition.html

27 points by okket 8y ago

Nice try Mr. Moth.

sydd 8y ago

Sadly there are a lots of flaws of LEDs, I think they are put in the spotlight a bit too early. While they are a lot better than previous light saving technologies (like CFLs which took a minute or two to warm up), most of the bulbs in the market currently have lots of drawbacks: - Their CRI is pretty low, around 80. - They flicker causing eye strain. There are now LEDs that solve both, its just a pain to find them (and cost 2-10x more than other LEDs.)

iainmerrick 8y ago
How do you go about finding high-quality LEDs? Are they easily available in standard bulbs?
- toss1 8y ago
  Just tinkering, I've found several factors are important. First is the color temp and CRI of the bulb/chip; make sure they match your application. Sometimes mixing bulbs/chips works well to get a more pleasing & usable spectrum. I've also found that the strip LEDs with multiple colors and a tunable controller produce good results. Second, find a power supply/controller that has a very high frequency. LED's don't inherently flicker, and when powered straight from a source like a battery provide a completely steady light. The flicker is typically from a time-chopping brightness controller. Cheap ones may use 60Hz, which the eye can still see, especially in the peripheral vision areas (rod cells, sensing only grays detect motion much better, whereas color-sensing cone cells at the center of the visual field have a slower response so detect flicker less well). Ideally, get a controller well above 25KHz to also eliminate any audio artifacts. I'd very much like to see someone more expert chime in!
  - iainmerrick 8y ago
    Are there any dimmable LED strips that operate by fully illuminating X% of the LEDs? As opposed to time-slicing all the LEDs. I don’t know enough about hardware to know if that would be feasible. The flickering and whining is pretty bad in all the dimmable LED bulbs I’ve used (but I haven’t yet looked hard for high-end ones).
    - dbuder 8y ago
      For long life, LEDs need to be off some of the time, better to run at 20mA 50% of the time than 10mA 100% of the time. That always on warning light on your cheap electronics runs at low power and has a relatively high failure rate. You need to tune or shield the drive to avoid troublesome EMI.
    - thatcat 8y ago
      Yea, my desk lamp does that.
    - OnlineCourage 8y ago
      That severly shortens the lifetime of an LED, like by a factor of 10. So I would guess it is not common because much of the benefit that gets marketed is the longer lifetime. It is possible to build a better dimmer switch which actually works across the full profile of voltage variation but the problem then is you have to pay an engineer money and why do that when you can spend money on booze and dinners to win more sales contracts with your lighting distributors and get a higher ROI? The lighting world is a very consolidated place.
- lotsofpulp 8y ago
  I haven't had any problems with the GE Classic LEDs: https://www.lowes.com/search?searchTerm=ge+classic+led https://www.lowes.com/search?searchTerm=ge+classic+led
  - sydd 8y ago
    Sorry, they are likely crap. If there is no Ra/CRI value given its 80.
- sydd 8y ago
  Yes. Just google for stuff like 95 CRI or high CRI bulbs. They are a bit more expensive than normal bulbs though. Some examples of good ones: https://www.waveformlighting.com/home-residential https://www.waveformlighting.com/home-residential https://www.mueller-licht.de/ https://www.mueller-licht.de/ And surprisingly IKEA Ledare bulbs are pretty good too (although not as good as the ones above)
JohnJamesRambo 8y ago
The cheap LED light bulbs I get at Walmart seem just fine. Have you bought them recently? I don't notice any flicker and their light renders colors better than my incandescents or CFLs ever did. They grow plants the best too, in my head to head tests.
OnlineCourage 8y ago
LEDs do not flicker, it is the pulse width modulation within the control circuit which causes flicker, which ultimately is due to poor design not the LED itself. CRI is based upon the patents held by the semiconductor fab which affect the type of semiconductor which can be used and how the phosphor is applied which varies. Binning (or statistical sampling) of LED chromacity improves over time across the industry. LEDs work great as spotlights actually because the most widely available lens material creates a sharp, direct light as opposed to a diffuse light. ;-)
lozaning 8y ago
Do they have LEDs now that only put out light in a small spectrum of filterable wavelengths? The city of Tucson for a long time resisted swapping all their street lights out from the existing sodium lights because local astronomers found it significantly harder to filter out the wide gamut of "junk light" from LEDs.

fabricexpert 8y ago

> Switch off a light bulb for an hour and you are saving illumination that would have cost our ancestors all week to create > But the price of light alone tells a fascinating story: it has fallen by a factor of 500,000, far faster than official inflation statistics suggest. This is a fantastic anecdote in favour of automation, technology, science and research. I can imagine how the sperm whale sailors, candle stick makers and matchbox makers felt when the light bulb started to become commonplace and replace their jobs. We will see the same arguments against progress coming through again and again over the next 100 years, I hope we continue to prevail in our growth and find a solution for those displaced when technology overtakes their job.

vwcx 8y ago
> I can imagine how the sperm whale sailors, candle stick makers and matchbox makers felt when the light bulb started to become commonplace and replace their jobs. And now the match industry has an upper-end, boutique product for wealthy millennials. Markets in everything. http://skeemshop.com/apothecary-match-bottles/ http://skeemshop.com/apothecary-match-bottles/
- nkrisc 8y ago
  Huge, dim "Edison" bulbs also appear to be trendy. The cycle seems to be accelerating.
henvic 8y ago
You are probably familiar with... but for those who aren't... Here is something cool to read by Frédéric Bastiat, a French philosopher during the 19 century: http://bastiat.org/en/petition.html http://bastiat.org/en/petition.html