Tuesday, August 13, 2013

Making Money With LED Lighting

The money to be made with LED lighting will go far more to the users, than to the sellers. Versus doing nothing, the money to be made depends only on how soon you are bold enough to act. You. Every ordinary person who only is obliged to accomplish things otherwise in darkness. You will be spending the money not saved if you do nothing with such opportunity, Don't fail to act.

This post is aimed at family which recently let me install fourteen Sylvania 70732 LED Disk Lights, $35 each on sale and emptying the inventories of two Lowe's stores in Denver. $490 there. I also spent $100 for involved dimmers, needed where before darkness was suffered. Now there is light to spare sometimes. I told these "investors" they would get their money back in a year. Showing this is not simple. It's a lot of money. I couldn't show them supporting argument from powers that be. A 7.5% sales tax added to the cost. A needless luxury? Denver, like Portland, still offers no rebates for residential LED lighting. No one cares what you do, or how you do it.

Before getting to the math, create a summary of involved Brightness Numbers. Our needs are for useful task illumination, whether just reading a book, keeping out of danger, or guiding a tool. Light intensity upon a task is not measured in lumens. A Brightness Number with standard definition yet to be established, expresses the task light intensity, integrated lumens in a unit work space. I define B4 as the useful task illumination from a 100 watt point-source bulb, and find that fully-presented directional light from a 4" Glimpse light, 300°K, 450 lumens, is matched to the task illumination of assorted "100 watt" point-source bulbs. The Brightness Number for any other fully-presented LED light will be proportional to its measured lumens, whatever the task and location/ size definitions. 

We must become fully aware of a roughly times two advantage that directional light has, in illuminating a task, vs. that old point-source candle. We used point-source light, only when that was all we had. Down lights were a step in the direction of lighting efficiency, if point light really received concentration in a well-directed reflector. The ideal light now is in the natural directionality of a glowing plate, usually left to just beam away without guidance. 

Times-two efficiency vs. point sources is yet to be emphasized in product marketing, but I have one public acknowledgement to share. I think a number like this is inferred in "efficiency" numbers, at page 3 in this Lithonia document. The Lithonia numbers acknowledge that CFL point sources are inferior to incandescent, CFLs beaming very little where needed.

Brightness Numbers appear in the following table of information and math operations.

I replaced a mix of bulbs in the fourteen can lights, mostly foolishly-employed CFL bulbs shining out very little of their light. The change of house cheerfulness is dramatic, especially in bathrooms.

Differences in the column, Savings vs. Reference are directly usable to infer time until investment is recovered. Forget the dimmers investment for now and think only of the bulbs hauled out. Each Sylvania plate LED will save at least $150 in 35,000 hours, more than was saved by just moving on from incandescent bulbs. How long does it take to save just the $35 luminaire cost? Not more than about 8000 hours. That's 2.7 years at 8 hours per day. Some lights will run eight hours a day. Payback time isn't the year I had promised. Maybe I said two years? There were incandescent bulbs replaced. Payback for them, is in less than a year, if operated five hours a day.
In hours, Payback in replacement of any incandescent bulb with the Sylvania luminaire is as:
Payback/35,000 = 19/396.    Payback  = 1679 hours
If used five hours per day, Payback = 0.9 year.

Whatever, and if someone can offer helpful correction of my thinking, payback is better than anyone should expect from money in any other investment, including almost all other forms of "weatherization."

Money back on the dimmers? If a dimmer works only one light, longer payback of the larger investment will bother.

Oh, about that Costco Luminus LED  light at bottom in the table? It's OK. Lots of brightness probably to be dimmed. Same savings. Same 65 lumens per watt technology as the Sylvania 70732. Tight against the ceiling it may be a better block of a leaky can light than the Sylvania 70732. I think the can retrofit is easier with the Sylvania 70732, which does not demand that the can have clips to engage springs. I still want to eliminate attic floor cans, know how to do so in all cases, and want to replace cans with junction boxes. I hope the Costco offering doesn't encourage anyone to newly install a light can. Use a junction box!

Please see all posts on blog subject LED Plate Lights.

Early Adoption Is Good:
At 7/29/2014, add comment on "early adoption." You will not save money by waiting for an improved version of an acceptable product. I have customers still happy with Version One of Sylvania 70732  lights and with 6" Glimpse , both now superseded by better lights. Where a customer is not happy with imperfect dimming or with the mild buzzing of Glimpse lights, I will take them back, credit half the material cost I and they paid, install the improved light at my cost of the light, and will give the returned light with disclosure to another customer.This is good for everyone. I hope other installers will follow my example.

I will not give the less-perfect light to charity, where the deficiency would not be disclosed. I imagine efficient-lighting informed charities, where I might donate even live CFL bulbs and fixtures now unwanted. Where a light might last forever, individuals too will look for means to move on to new products.

Know that where an energy-saving investment survives for twenty years, or sixty, there are important returns because energy costs grow much faster than inflation. Please help me to imagine the more-complete payback math where there is accounting of inflation and present value in energy conservation, of a perpetual return on investment, Perpetuity Math .


steve thumb said...

It was a really informative article. The LED light power holds the future for sure. and, subsidy needs to be provided by the government agencies on LED lights. It will save energy and money both.

Rose Marry said...

Energy Saving is one of the big questions for todays world. By LED Lights you can save mpre energy other then other lights.

justin6case said...

You say "I hope the Costco offering doesn't encourage anyone to newly install a light can. Use a junction box!". Could you describe how you do this? The standard boxes seem too small and not deep enough. I also don't see how to attach the fixture to the box. A blog post about this would be great. I'm finishing my basement and would really love to use the $22 Costco option with a standard box as it would save a ton of cash and provide me with more flexibility as far installation location goes.

Phil Norman said...

Dear justin6case, You may find many examples of LED light placement in deep junction boxes. In this blog, search RACO 175. For your information, I have also placed details that may be useful to you, in a Picasa Web Album:

julian Smith said...

Amazing post, really looking Very nice,

Design Lampen

justin6case said...

Thanks for the reply. My issue with the Costco light, and most other lights made to be retrofits, is the large width and depth of the assembly, most of which usually appears to be a heat sink. Then there is the issue of how to attach a light like the Costco light to a standard junction box, assuming I could get the whole assembly into a deep junction box. Lights like the Glimpse don't have this issue, but they're almost twice as expensive. Since I'm finishing my basement with approximately 30 of these, and that adds a lot to the cost.

There seem to be only a handful of lights designed to be surface mounted as of right now. If you're aware of more than just the Glimpse and the Sylvania 70732, I'd be interested in hearing about them, especially if they were cheaper.

The other issue I had with the Sylvania I recently picked up was the startup delay and the inability to turn on at all with the dimmer below about 1/3 to 1/2. This is unacceptable, but I wonder if this could be solved with different dimmers.

One more thing, I read somewhere that a heat sink is important even for these LED lights. What are your thoughts on this? Obviously, the Glimpse and the Sylvania have foregone the heat sink. Will this significantly impact the life of the unit?