With informed good choices, abundant lighting is already a resource available to all, at little cost. Abundant task lighting is crucial to our safety and productivity. Lighting for decor, not wasteful, may be more abundant, interesting and beautiful.
Light, clean air, good potable water and internet broadband are no-cost essentials of a just society in which the potential of every person may be achieved. Of these essentials, "free" light is the nearest to hand, perhaps not corruptible through stupidity and greed. With lighting we are on the verge of considering power draw only as it relates to potential of generation off-grid. Reduced in cost by more than 90% vs. that from dumb incandescent bulbs, we may choose to use light more abundantly, for safety, productivity and better quality of life. The potential is deserving of a global campaign to do away with light bulbs, just as we did with awful CRT computer and television screens. Again, the solution is in durable, flat things. And, let those flat things for awhile include BR30 LED flood bulbs directed from cans, functionally the same as any LED disk downlight.
This post will evolve over several weeks. Please watch it grow. And, know conclusions have already been expressed here over the four or five years largely mis-spent since excellent LED disk downlights became available for home installation. LED lighting will improve global quality of life and productivity, while hugely contributing to saving of grid electrical power used for residential lighting. Only about 10% of the potential has been achieved so far in the USA. Ref: Adoption Report, USDOE, 2017 .
Here are discussions in this blog:
Focus please on the word Brightness of the post title. Go with me to the linked Wikipedia article, and find disastrous confusion sowed by the US Federal Trade Commission in the matter of Lamps, the topic here:
The United States Federal Trade Commission (FTC) has assigned an unconventional meaning to brightness when applied to lamps. When appearing on light bulb packages, brightness means luminous flux, while in other contexts it means luminance. Luminous flux is the total amount of light coming from a source, such as a lighting device. Luminance, the original meaning of brightness, is the amount of light per solid angle coming from an area, such as the sky. The table below shows the standard ways of indicating the amount of light.
Today, dictionary.com has
lamp (noun)
1. any of various devices furnishing artificial light, as by electricity or gas.
There can not be a justification by FTC, to imagine and apply only light bulb point sources as lamps. And, of course an LED light bulb is not a point source. An LED bulb hemispherical lens glows to the side with task lighting efficiency of less than 30% of total lumens. About 70% of typical A-type LED bulb illumination is sent from a circuit board parallel with the base; a nasty and dishonest trick when upright in a table lamp or horizontal in a ceiling fixture. A large fraction of emitted light is lost in the thick diffuser. A wasteful device must not be promoted as other than decoration, without offer of purchase incentives.
A cheap and short-lived A-type LED bulb has sideways illumination like that of the old 100 watt incandescent, and is 40% brighter end-on. If used in a table lamp for reading, 40% of power is wasted.
Here is proof from test stand comparisons . At left "100 watt" incandescent bulb. At right EcoSmart ICES-003/B LED, 800 lumens, 10 watts, 3000°K. At full power. The EcoSmart is turned 90° to illuminate the screen with cast from glow of the lens hemisphere as it might in a table lamp or horizontal ceiling fixture. The EcoSmart side illumination is about 500 lumens, equal to that of a "100 watt bulb."
At left "100 watt" incandescent bulb. At right EcoSmart ICES-003/B LED, 10 watts, 3000°K. At full power. The EcoSmart is now straight-ahead to the screen and quite superior to a 100 watt bulb, the effect of 800 lumens, not the useful 500 lumens of a 100 watt bulb. Judge that the EcoSmart if placed upright in a table lamp or horizontal in a ceiling fixture is with usefulness ratio 500/800, about 40% energy waste.
We must go back to the correct usage of brightness as luminance, to inform our decisions, as we develop and select luminaires that ever-better, make light a cost-free resource to enrich human activity. Luminance is first a measure of the illumination to our eyes, of tasks at hand. Nearly as important, it is the test of glare as we gaze upon the luminaire. Glare as a nuisance or hazard, is not regulated and not listed in competition for purchases. Lights continually cheapened and glaring, discredit the switch to LEDs for energy conservation. Where best LED lights will serve essentially forever, we can afford that they be built without weak electronics, easy to look at.
Following the FTC mis-direction, we are taught that lumens count, luminous flux in all directions, is the modern way to compare lighting choices.
Here is an example:
C/Net, Smart Home
Watts vs. lumens: How to choose the right LED light bulb
Article by Alina Bradford, May 9, 2017
These comparisons are meaningful only for light in antique candle form, as point source illuminating a beam angle of about 320°. Achievable brightness of such old-fashioned bulbs actually can't exceed that of the well-known "100 watt bulb." Wiring that fed a 150 watt bulb was usually destroyed by heat. The table perhaps consciously under-values LED lighting, where LED tricked to look like point-source incandescent and CFL bulbs, has not been offered at more than about 15 watts. All LED luminaires of higher wattage are of other form, as directional flat plates, the natural display from diodes on circuit boards; and do not belong in this table. Disregard as ridiculous, "corn" LED bulbs at the high end of table wattage. Striped light thrown about a room by a corn bulb, is ugly.
About half of point-source light is fully wasted where the purpose is task illumination as in reading. The comparison prevails where something is sought to fill A-Series light bulbs with their global confusion of sockets, in USA and other countries with 110 volt mains, E26 threaded.
We have long had point-source lighting that is not dissipated as point-source, confusing a relationship of watts to potential task illumination. Extremely shiny back reflection within a light bulb does the job most simply, forming a downlight from a ceiling whether or not the bulb is recessed, or displayed upon a pendant with or without a decorative shroud.
Again, before LED lighting became practical, interim CFL flood or spot bulbs, muddied watts as a measure of brightness, where a mammoth point-source has lots of internal mis-direction and waste. Worst for waste with simple CFL bulbs, is common practice of setting point-source light in cans that hide more than half of the light output.
The wrong teaching is in failing to distinguish lumens count from directional light, most clearly understood where it might be uniform, flat OLED, from wastefully-thrown light of point source bulbs.
From a human perspective, the Sun is a uniformly-bright disk. Brightness within that disk sets the example of other luminance examples, in the table that follows. A luminance value 0.05 lumens/mm2 is evident as a luminaire-design target.
Hereafter let Luminance be a controlling factor in luminaire planning and design.
Look at luminance numbers for some existing edge light LED examples:
Cooper SLD6: 0.064 lumens/ mm2
Conturrent 4": 0.074
Lithonia WF3: 0.228
Lithonia WF4: 0.124
EiKO 5": 0.059
Try imposing a uniform lens luminance limit of 0.05 lumens/ mm2.
Tabulate lumens and lens diameter at this limit:
Let there be greater lens luminance, to get about 500 lumens from a 4", 100 mm lens diameter.
These are candidate lumens targets for a range of lens and called size-of-light, in inch, 25 mm increments.Let suggestion of luminaire description by a "brightness number", instead be a series of round-number lens sizes. And, let those size numbers not be those of the lens rim outside diameter.
Please look at last, for discipline in luminaire offerings, those volunteered by China factories without global leadership, and by specifiers everywhere, for competition upon reasonable glare numbers. For greatest number of directional lumens with typically 120° beam angle, we will choose uniform-glare OLED, or edge light luminaires with proven effective 90° downward turn of light.
Where edge light lumens might be proportional to strip diameter and circumference and luminance is then related to square of diameter, LED edge light strips will be intelligently related to square of diameter, rather than to diameter.
Efficacy based on task illumination will easily be with more than 90% reduction from energy cost with LEDs, vs. cost from A-type point source incandescent bulbs. Improvement will not be the 75% reduction imagined with A-type LED bulbs that look like A-type incandescents and fit in any old luminaire. If LED strip edge lights become the production standard, I hope the diode strips will have a salting of phosphor colors, to better resemble sunlight effects in human vision. Notice to a wished manufacturer: Better, with edge-light luminaires employing LEDs on flexible strips, choose RGB diode strips for full-spectrum, tunable white.
This just in 2-7-2018:
Offered at Gordon Electric . But, I can't find these except through email links, among the vast forest of distributor offerings.
Do can light retrofits compete with an edge light surface mount simple future?
All of these Sylvania offerings are with circles of uniform brightness, here presumed 4" diameter.
All of these are too-aggressive cramming of light, unmindful of hurtful glare. Can lights must not be used for more than "65 watt incandescent equivalent." I bet that 16-watt offering runs quite hot, and I won't buy to try. For residential installation, there is no virtue in such large light concentration. In recessing deep within a can to not see the glare, expect that about 20% of the light energy is thrown away.
In support of this post, and for decision upon lighting selection in my own kitchen remodel, I have purchased several candidate LED edge lights. I will look for useful consistencies in arrangements and sizing, not expecting to find exactly what I want. I want pretty 500 lumens LED edge lights with 4". 100 mm active lens area. Here is that remodel scheme:
Now in March, 2018, I have planned to use fewer lights of larger size. I thought to use available Nicor DLS10, but they are configured only for individual constant current drivers. Choose edge lights that, like all tape LED lighting, are configured for a constant voltage driver. To employ a common driver, luminaires must connect in parallel. I believe that light engine circuit boards are generally wired to want a fixed current.
My kitchen remodel has been lighted so far with only the two lights of Circuit 1, an out of the box Nicor DLS10, and a still-excellent first-generation 6" Glimpse bought in 2012 as Home Depot T91. It is in further circuits that I want innovation, allowed as trial, in my own home.
Switching as follows is fully tested, operating only Circuit 1 with 4-way control.
On a second try, I purchased this as a common driver, with constant voltage output, dimmable:
Mean Well PWM-90-36 Report, with installation instructions.
Buy at DigiKey
From the instructions, take the wiring illustration.
Now choose the needed dimmer, with assistance at Lutron.
Buy at Bees Lighting .
Lutron DVSTV Instructions
With this, observe Nicor DLS10 on a remote constant-voltage driver. Draw power through a Kill-A-Watt meter and observe exceptional brightness at dimmer full power.The DLS10 should draw 15 watts without dimming. Instead at full power it draws 28 watts. I think this proves the DLS10, and probably all like luminaires with a coupled external driver, are the feared constant current device, to have shortened life or simply to be fried, on a constant voltage driver. Sellers of drivers have been through this before. I am lucky that my DLS10 may have survived unharmed. I have my answer at last for the driver seller. Already I had lost interest in LED downlight luminaires on circuit boards, because of manufacturer inattention to glare and to dead-bug litter. There is not one such circuit board luminaire on offer now, that I would happily offer to a customer. There is certainly not a winner, flying off store shelves.
I want to move on to our future with LED edge-light luminaires, surface mounted without demand of large ceiling holes, new junction boxes or new can light bodies. I hope I can come up real soon, with means to fill dark spaces in my new kitchen ceiling.
At September 2018, I must at last complete my remodel kitchen lighting. Here is the illumination with only Circuit 1 lights:
Here is my cut-in plan for fifteen more lights generally 500 lumens each, Commercial Electric 74203 . It will come out brighter than 300 Lux. I believe we want always a bit more light as it becomes affordable. Lighting placement in a completed room involves measurements relative to any convenient structure, planned with computer graphics.
I challenge low ambitions for saving of energy in residential lighting, in current rules, 2015 International Energy Conservation Code, IECC, Chapter 4 :
R404.1 Lighting equipment (Mandatory).
Not less than 75% of the lamps in permanently installed lighting fixtures shall be high-efficacy lamps or not less than 75% of the permanently installed lighting fixtures shall contain only high-efficacy lamps.
Exception: Low voltage lighting.
Point source CFLs and other line-source fluorescent lamps are offered as these "high-efficacy lamps," as seen another 2015 IECC statement, Chapter 2, General Definitions :
R202 GENERAL DEFINITIONS
HIGH-EFFICACY LAMPS Compact fluorescent lamps, T-8 or smaller diameter linear fluorescent lamps, or lamps with a minimum efficacy of:
60 lumens per watt for lamps over 40 watts;
50 lumens per watt for lamps over 15 watts to 40 watts; and
40 lumens per watt for lamps 15 watts or less.
These limits mean nothing for residential LED lights, usually less than 15 watts, and efficacy better than 50 lumens per watt. Limits are in ignorance about usefulness of silly point-source LEDs that fill our stores. About half of the lumens of point source and linear lamps are wasted, not at all contributing to task illumination, but perhaps coloring walls and ceilings. The lumens per watt of point and line sources must be reduced by half, roughly, for comparison with directional light broadly aimed at a task, as with large beam angle downlighting. A point-source LED bulb at 50 lumens per watt is useless for task illumination, and is not high-efficacy.
The US Department of Energy seems to be the author of these rules, and does offer improvement for 2018. Here are seven residential energy submittals by US DOE, for 2018 IECC:
https://www.energycodes.gov/doe-proposals-2018-iecc#background
This is claimed for R-5, High-Efficacy Lighting (R202)
Redefine "high-efficacy" to acknowledge the marketplace penetration of LED lamp technologies. The availability of LED lamps is growing rapidly and prices are falling just as quickly. This proposed change attempts to increase the lighting efficiency in homes by encouraging higher efficiency Light Emitting Diode (LED) lamps while still permitting many CFL technologies. LEDs have been steadily gaining popularity over the last few years due to their higher efficiencies, better light quality (relative to Compact Fluorescent Lamps), and remarkably long lifetimes compared to traditional CFLs or incandescent lamps.
Proposal as PDF
R202 GENERAL DEFINITIONS
HIGH-EFFICACY LAMPS Lamps with a minimum efficacy of 75 lumens per watt.
Analysis as PDF
This DOE proposal is progress, but lacks recognition that efficacy is not simply lumens per watt. It also pushes the envelope on achievable directional-LED efficacy at a number of 75, where in 2015, I am not aware of any compliant luminaire on-offer in our stores. I admit that 50 lumens per watt might be just fine until one is trying to pull needed light from a limited-capacity on-home photovoltaic array.
Here is one resource describing an alternative measure of efficacy, a Brightness Number.
Looking For A Reading Light (a printable pdf)
A Brightness Number rates delivered task illumination independent of light form. It assesses this number in side-by-side comparisons of a candidate with a known reference. The judgement is by human eye and by digital camera calibrated to record scenes in keeping with human vision. A 100 watt incandescent bulb is assigned Brightness Number B4. A directional light perhaps called "wide flood," of beam angle greater than 90°, say 120°, is a practical offering, B4 at 450 lumens. If the color temperature of the 100 watt incandescent reference is 3000°K, as I observe, choose a 3000°K LED as human-preferred, at reference B4. A world-accepted measure comparable to this Brightness Number might be at other color temperature, where some people like yellowing "warmth" of 2700°K better. Perhaps the standard and the wish for our home lighting, should be with broader spectrum, where in an LED with a large number of diodes, blue-LED coloring phosphors are a mix of yellow colors. Color-tunable OLED , with variable relationship to now-ancient light forms, will demand some flexibility in a Brightness definition.
The goal in our advance of efficiency in residential lighting shall be that a number of lumens delivered upon a task, shall be achieved at ever-less consumed power and overall measure of operating cost and environmental harm. Point-source lights will never measure up to this goal, and must now fall away from our high-efficacy future. A point source light will always be half as efficient as that beaming from a plate. It is simple physics understandable by anyone. LED and OLED elements are inherently least cost where flat, and that is a blessing. Let us then deploy these elements fully-revealed, a least amount of light blocked by decorative or practical aperture and by obscuring lenses. Let us place them flexibly and artistically, with least holder cost and with ease and safety of change-out. (Handling as to paint a ceiling, or from whim of rearrangement, never failure.) Let them generally be downlights, aimed downward from the ceiling or a lower-elevation pendant. Where LEDs might work essentially forever, let safety include absence of fragile elements that can not tolerate expected dropping, through lens breakage or failure of electronics. Let electronics durability match that of served diodes.
Most-efficient luminaires will not include the needless added expense and generally-awful compromise of a home's shell integrity, of a holder can. The best opportunity is to deploy luminaires in new low-voltage DC circuits, 24 vdc the apparent standard. Advocacy in this is expressed in a Google + Community , and in a Pinterest page .
I have offered this, as one suggested better statement in 2018, submitted to IECC:
Specific new rules of Referenced Standards shall support transition toward distributed local electric power generation and shall promote most-efficient lighting and appliances. At 2016 revision, special attention is given to most-efficient LED downlighting. Mention of passing forms of light is not helpful. In the process of evolution, less-efficient light forms, including all point-source bulbs, will be tolerated and not regulated, only as less-used decor. Market forces including evolving absence of Energy Star recognition will give natural drive toward best luminaire efficiency. Delivery of better luminaires is very important, as inspiration for all other efficiency gains. Lighting used abundantly at little or no cost, is important to productivity and quality of life. We do not develop purpose and hope, in cold darkness.
In reasoning that supports this submitted text, I expressed my understanding of math, to address cost impact of encouraging light forms that do not include can lights. I wish to develop that math, here. Illustration will include real examples from my experimental work as a weatherization contractor. My work is carefully documented and reported, to ensure a process of constant learning of better practices.
First, consider work done in a Southwest Portland Oregon attic, February- March 2014. The home, as usual, is notable as one where other contractors, following the guidance of regional policymakers Bonneville Power Administration , and Energy Trust of Oregon , would have found no work to be offered. The job was first an example in challenge of policies. I have needed to do more with my records, in challenge of existing policies and practices in lighting installation.
Prior posts for this Southwest Portland home are:
Daring To Collapse and Rebuild Crummy Loose-Fill Fiberglass Insulation
and
Math Of Under-R12 Attic Floor Insulation Rule, For Incentives
Photos for this post are in a captioned Picasa web album, Graphics for a can light replacement math study .
The Lighting Innovation:
It's routine. I do this wherever I fix attic insulation, by my own initiative.
I eliminated six Lightolier non-IC can lights. All had large annular gaps unobstructed at topside. If cans had been IC and covered, the insulation would have been fully blackened. The cans themselves were beautifully metal-spun and nearly airtight, high end for 1988 construction. What a waste.
The can annulus diametral clearance was 7” - 6.25 = 0.75”, quite large. The frame was not pushed against the ceiling, and probably did not further constrict the passage of leaking air. Each can light had a gap of up to 7.8 sq in. Apply Insulation Math for a Portland, Oregon home with a common 88%-efficiency furnace. The annual cost of heating lost air is $0.555*Path Area, $4.30 per year. At four places I replaced a 65 watt incandescent downlight with a 750 lumens 14.5 watt LED. Another can that had a long-dead 65 watt incandescent was patched out. At the sixth can, over-sink, I installed a 450 lumens 9.5 watt LED in place of a 150 watt incandescent downlight.
Apply Insulation Math . Completing insulation in the floor should save, at each light:
$2.4 * Baffled Area, sf* (1/3 - 1/50) = $0.75 * Baffled Area, sf
= $1.30 per year for an 18” baffled circle (1.8 sf).
= $3 per year for 4 sf uninsulated over the kitchen sink.
There is about $6 per year typical savings from air sealing and insulating each very leaky non-IC can light.
Here is a sampling of the job photos:
The found conditions are typical, an uneven bed of loose-fill fiberglass originally thought R19, trampled. Non-IC can lights are shrouded against insulation, by floppy R11 batt cylinders.
In thirty minutes, and for cost of about $25, I replace the 7" can hole with a sealed-in drywall patch and RACO 175 junction box, texture matched.
This is the appearance of a can light patch, from the attic, now readily accessible by a wonderful drop-down fire-rated attic ladder.
The loose-fill always misses a band of at least 12" at attic eaves. Here there was no insulation under the batt shroud of a far-out non-IC can, over the kitchen sink.
Mud wasps will hate me.
Conserve electricity, in addition to $6 per year savings through air sealing and completion of insulation at each can light.
Vs. a 150 watt incandescent flood, a 4” Glimpse saves $368 + 1 = $369, over 32 years. Vs. a 65 watt incandescent downlight, a 6” Glimpse saves $380 - 136 = $244 over 32 years. Total savings operating four 6” Glimpse and one 4” Glimpse vs. six found lights, are: $369 + 5*244 = $1589. Divide by 32, for first-year savings: $50. Call this $8 per light. Include the savings from sealing and completing insulation over the light, in the payback study. Those savings, with very-leaky non-IC can lights are about $6 per year. Total savings are $14 per year. It is right that the savings for a light eliminated are included, where new LEDs are much brighter. Five LEDs will give much more light than six old incandescents, and the LED lights might be dimmed most of the time. There might be even more savings, where old lights might have been brighter than needed, much of the time, and were not dimmable.
A savings of $14 in the first year is presented as typical of the opportunity in any can light replacement with a disk LED giving better illumination. The savings will persist indefinitely.This is an energy conservation savings subject to growth with rising cost of electricity. Perpetual energy savings are far more valuable than simple savings of money, as presented in post Perpetuity Math For Energy Conservation .
If the cost of electricity goes up with cost of scarce fossil fuels, a geometric rise of 10% per year , the future savings become far more important than those of an initial period where an investment is simply repaid. If you will use a new light where first-year savings are $14, Present value through twenty years is times-44, or $616. Present Value through thirty years is times-110, or $1548. Please seek a constructive understanding of such reality-based large numbers. First see that a payment of much more than $60 could be offered in exchange for the wealth now-yours, however large you perceive it. Be very happy if someone would do the work right, for $120. My work at $60 will be in short supply. Next, imagine that vs. doing nothing now, you might get your lighting forever after, at no cost, from your off-grid disaster-preparedness rooftop photovoltaic array and battery interface. You will want as much result from your investment as possible, not just some or all of your lighting, but maybe the charging of an electric vehicle off-grid! You will want lights of best-available efficiency, but know that fifty lumens per watt technology , durable and inexpensive since 2011, already gives nearly all of the achievable savings. Don't expect to save more than fifty cents per year for each luminaire, in a doubling of efficacy, from 50 lumens/ watt, to 100 lument/ watt. That's another $22 of present value through twenty years; not nothing, but little enough that one will only lose, waiting to act when better products arrive.
A basis presentation is done, I hope. Get back then to challenge of US Department Of Energy actions toward the 2018-2021 International Energy Conservation Code. The need in better building codes is about equally to save electricity, and to save thermal energy by eliminating awful bulb holders. It is about delivering needed task illumination, with ever-decreasing cost, within a power budget. How about this as High Efficacy definition? Where arrays of luminaires deliver a set amount of task illumination, the lifetime operating cost of high-efficacy luminaires is less than 10% that of 100 watt incandescent bulbs. A decent LED as A19 in a crummy can, will not measure up, since can energy losses must be counted. No point source light will measure up.
Look for that 90% savings vs. 100 watt incandescent, in this table. See that it is achieved now with very inexpensive LED disk lights, including GreenCreative 40834 with AC LED fitting even on a fully loaded ceiling box. No can lights, please. Where LED disk lights might serve for 100,000 hours or more, we already are well beyond 90% reduction, still with "efficacy" around 67 lumens per watt.
As a single parameter defining "high efficacy," Brightness/ Watts > 0.5 works. And maybe Brightness/watts = 1 is an achievable goal of inexpensive luminaires, 450 directional lumens from a 4 watt LED, 125 lumens per watt in useful directions. Brightness Number = Watts? Why not?
> 75 Lumens/watt does not promise efficiency, and seems a mean effort to continue sale of point-source CFLs, that often are ugly and not dimmable. Can CFLs get that efficiency? Why would we try?
