LED replacement

[Besoeker]

Also, depending on burn time per year and energy cost, the expected payback period assuming common interest rate might not meet expected project ROI.

I agree. That's fairly self-evident. If you have an average operating time of say, 5 minutes a day, it would be hard to make a case for changing. Even on the basis of being a greenie.

However, in the example of my office, the one at home, I normally spend at least three hours in the evening responding to emails, deleting those that are irrelevant, and attending to non-business matters. Say 1,000 hours in round figures.
At current domestic energy costs here, the return on investment for changing to the more efficient technology is about 70% for the first year which vastly outstrips the cost of the money invested in pretty much anything else. In the following years up to the expected lifetime of the unit which could be at least another ten years, there is no investment. So the subsequent savings are free money.

Say you have an old V8 car that gets 12mpg.

Like the V-12 like in my avatar?
Very smooth, very quiet, and very quick.
And very thirsty. With UK fuel prices and a growing family, it had to go.

 

[Electric-Light]

At current domestic energy costs here, the return on investment for changing to the more efficient technology is about 70% for the first year which vastly outstrips the cost of the money invested in pretty much anything else.

Relative to incandescent. Such replacement includes fluorescent. LEDs certainly cost more and are on par with screw-in CFLs and not as efficacious as tube fluorescent in most cases.

 

[weressl]

With respect, I think you might be quite mistaken about that.
The cost of running the LED equivalent downlighters in place of the halogens in my office is about ?50 ($80) less per unit over projected lifetime. Which is about ten times the cost of the LED unit. So even if the halogen cost nothing, which it doesn't, and didn't need replacing, which it would, I'd still save my 50 squid minus the cost of the lamp.
It's a no brainer.

What do you pay for electricity?
What is the cost of each of the different sources?
One time installation cost premium, over replacement of the halogen, needs to be absorbed, right?
What is the heat rejection difference?
Why halogen? What is the life expectancy of that?
Is it still more efficient than a CFL?

 

[Besoeker]

What do you pay for electricity?

For domestic it varies a bit depending on consumption. The first tariff might be around ?0.18 per unit falling to ?0.12 above a given level.

What is the cost of each of the different sources?

The cost or what we pay for it?
What we pay per unit is to the supplier.

One time installation cost premium, over replacement of the halogen, needs to be absorbed, right?

Indeed. That, and subsequent lack of replacements.

Why halogen? What is the life expectancy of that?

Halogen wasn't our choice. They were here in the conservatory and my office when we moved into this house.
About a dozen in total. Along with a fair number of conventional filament bulbs.
All that have failed, and that's most, have been replaced with energy saving units. Not one of which has failed in the six years we have been here.

Anecdotal,I know.

 

[weressl]

For domestic it varies a bit depending on consumption. The first tariff might be around ?0.18 per unit falling to ?0.12 above a given level.

So that's about 2.5-3.5 times of what I pay and considerably more that manufacturers pay. As I understand the UK cost is greatly impacted by the absorbed cost of the N Sea wind generators.

The cost or what we pay for it?
What we pay per unit is to the supplier.

Sorry, I meant the different lightsources.

Indeed. That, and subsequent lack of replacements.

Labor cost will make the difference. Of course if it is your home then it is free labor.:happyyes:

 

[Besoeker]

So that's about 2.5-3.5 times of what I pay and considerably more that manufacturers pay. As I understand the UK cost is greatly impacted by the absorbed cost of the N Sea wind generators.

A lot of things are more expensive here. Cars, fuel, clothes, energy etc.
On-shore and off-shore wind farm projects are subsidised by the government i.e. taxpayers. To what extent, if any, that impacts on the price of electrical energy, I don't know.

Sorry, I meant the different lightsources.

Ordinary incandescent light bulbs, if you can find any, cost about ?0.40
A GU10 50W halogen is ?1.00 each in packs of 10 from a distributor.
I've seen CFLs sold for less than ?2.00
And LED lamps are upwards of ?5.00.

Labor cost will make the difference. Of course if it is your home then it is free labor.:happyyes:

I meant that, by using low energy lamps (CFLs or LEDs) which have a long life, you save on the cost of the replacement lamps you would have with incandescent or halogen.

 

[weressl]

A lot of things are more expensive here. Cars, fuel, clothes, energy etc.
On-shore and off-shore wind farm projects are subsidised by the government i.e. taxpayers. To what extent, if any, that impacts on the price of electrical energy, I don't know.

I have read an analysis that claimed that the original estimates of how much they will produce were significantly higher than the actual production and that themakeup of the shortage is extraordinarily costly. Those were plants to be mothballed and credit were taken for the conomic analysis, so now it hits with a double whammy.

Ordinary incandescent light bulbs, if you can find any, cost about ?0.40
A GU10 50W halogen is ?1.00 each in packs of 10 from a distributor.
I've seen CFLs sold for less than ?2.00
And LED lamps are upwards of ?5.00.

Close enough, but it seems that the LED's are subsidized. (Those prices are even less than you can get them for on e-Bay.)

I meant that, by using low energy lamps (CFLs or LEDs) which have a long life, you save on the cost of the replacement lamps you would have with incandescent or halogen.

Yes-yes, of course.

I have not seen in the economic analysees the total delivered lumen/hours throughout the life of the lightsource used, taking decay into account.

If we thought that fluorescent flickering is annoying wait until you see an LED power supply crow-baring and turning on/off endlessly.:rant:

 

[Besoeker]

I have read an analysis that claimed that the original estimates of how much they will produce were significantly higher than the actual production and that themakeup of the shortage is extraordinarily costly. Those were plants to be mothballed and credit were taken for the conomic analysis, so now it hits with a double whammy.

Far from being mothballed, more are coming on stream, another 15 or so already this year alone, the largest of which with 68 turbines and 156MW capacity just a stone's throw away from where I was born.
The total installed capacity in UK to 6,600MW as of April 2012. With a capacity factor of 30%, which many believe to be optimistic, the output would be about 2,000MW. By way of comparison, Drax power station, coal fired, is 4,000MW capacity and provides around 7% of UK use. From that, you could deduce that wind might be expected account for 3.5%. If they failed to meet expectations and produced half that, the shortage wouldn't be all that huge and, consequently, I can't see why an analysis would conclude it to extraordinarily costly.

The UK government has committed to (unachievable) CO₂ reduction targets which is why wind farm projects are being subsidised. And why you can't easily find incandescent lamps these days.
In the meantime our electrical generation infrastructure is on its knees. The vast majority is from fossils and nuclear and nuclear stations are being decommissioned and, until recently, none new had even got to the planning stage as successive governments sat on their hands and failed to commit to new build - it was not seen as a vote winner. Ironically, in the meantime we are importing from France at about the capacity of the cross channel HVDC link. We evidently didn't want nuclear here but were quite happy to import it from a country that is 70% nuclear.

Close enough, but it seems that the LED's are subsidized. (Those prices are even less than you can get them for on e-Bay.)

Well I did say from ?5 ($8) but yes, some are much more expensive.

 

[TNBaer]

I've run the math on interior LED lighting time and again. When it comes to replacing T8 tubes, LED tubes never produce an ROI. Ever. Period. Also, bear in mind that a single out of warranty failure eats dramatically into your ROI. If a T8 goes bad, you're out $3, if an LED goes bad, you're out $60.

And let's not even get into the UL compliance issues of replacing T8 with LED. In some cases the LED manufacturer claims to be able to use the existing ballast. In other cases to run line voltage to a tombstone. Neither are situations that UL would consider "safe" at this point in time.

 

[Besoeker]

I've run the math on interior LED lighting time and again. When it comes to replacing T8 tubes, LED tubes never produce an ROI.

Care to cite the numbers for your mathematics?

 

[Electric-Light]

I've run the math on interior LED lighting time and again. When it comes to replacing T8 tubes, LED tubes never produce an ROI. Ever. Period. Also, bear in mind that a single out of warranty failure eats dramatically into your ROI. If a T8 goes bad, you're out $3, if an LED goes bad, you're out $60.

Especially not in the NW.
Seattle City Light (90% hydro) and BC Hydro(all hydro) have among the lowest rates in nation. So low that data centers consider BC, CAN a good place to locate.

There's such a thing as a diminishing return effect which LED advocates keep ignoring.

At 12,000 miles a year, at 12mpg you're using 500 gallons or $2,000.
at 24mpg, that's down to $1,000, something a lot of common cars will get.
To double that and get 48mpg, you'll have to get something crazy like Prius but the saving per year now is only $500, yet going from a 24mpg to 48mpg car costs substantially more than 12mpg to 24mpg.

Just because going from 12 to 48mpg eventually produces a break-even point doesn't mean that 24mpg option should be overlooked.

There is some difference in gas prices across the nation, but not to the extent of electricity cost.
When doing retrofit calculation, its like comparing gas cost in US and England, because there's that much difference. Power in WASH DC is MUCH more expensive than power in WA State. Something like four times as much.

 

[Besoeker]

There's such a thing as a diminishing return effect which LED advocates keep ignoring.

I'm neither advocating LED lighting nor ignoring anything.
I can buy a T8 tube for about ?2 and it has an average life of 2000 hours according to my distributor's catalogue.
A GU10 LED has a life quoted as >15000h. And it costs ?5.50. It's a retrofit so no installation required. Other than plugging into the existing fitting, obviously. But that's no different to changing a bulb.
With my 1000 hours a year example I gave earlier, the T8 would have a life of two years and the LED unit fifteen years.
So if I buy the LED unit I have an immediate cost of ?579. Had I chosen not to and invested the ?3.79 difference, it would have maybe accumulated to ?6.00.
The T8 would have had to be replaced about seven times.

At 12,000 miles a year, at 12mpg you're using 500 gallons or $2,000.
at 24mpg, that's down to $1,000, something a lot of common cars will get.
To double that and get 48mpg, you'll have to get something crazy like Prius but the saving per year now is only $500, yet going from a 24mpg to 48mpg car costs substantially more than 12mpg to 24mpg.

The Jaguar in my avatar did about 12 mpg on average. It was an up-market, expensive car. The current XKR is about ?78k here (about $125k) and does about 24mpg. Generally cars here with low fuel consumption are up-market expensive models. And we'd consider 24mpg low fuel consumption.


This was from my previous car:

It isn't a hybrid. It's a comprehensively equipped, four-door, five-seater, with a 130mph+ max speed.
And a third of the price of the XKR.

 

[BullsnPyrs]

I'm neither advocating LED lighting nor ignoring anything.
I can buy a T8 tube for about ?2 and it has an average life of 2000 hours according to my distributor's catalogue.
A GU10 LED has a life quoted as >15000h. And it costs ?5.50. It's a retrofit so no installation required. Other than plugging into the existing fitting, obviously. But that's no different to changing a bulb.
With my 1000 hours a year example I gave earlier, the T8 would have a life of two years and the LED unit fifteen years.
So if I buy the LED unit I have an immediate cost of ?579. Had I chosen not to and invested the ?3.79 difference, it would have maybe accumulated to ?6.00.
The T8 would have had to be replaced about seven times.

Your lighting comparisions are apple and oranges, with a typo thrown in for good measure. Modern t8 tubes are rated for 20,000 hours and more depending upon lamp/ballast combinations. A GU10 Led is more comparable to a compact flourescant lamp. From the Energy Star website.

Lifetime ? To qualify for ENERGY STAR, CFLs must have a rated lifetime of 6,000 hours or greater. The current average rated lifetime for ENERGY STAR qualified CFLs is 10,000 hours. With typical use of 3 hours per day, that?s an average lifetime of 9 years.

Totaly changes the payback. It is very difficult to make LED replacements the best choice based on ROI without very high electric rates.

 

[Besoeker]

Your lighting comparisions are apple and oranges, with a typo thrown in for good measure.

Quite evidently, you are not immune from typos.

Modern t8 tubes are rated for 20,000 hours and more depending upon lamp/ballast combinations.

Accepted.

 

[TNBaer]

Care to cite the numbers for your mathematics?

Sure.

Based on 12 hours a day and .15 cents per KWH T8 still wins. I assumed a two lamp 28 Watt low power ballast T8 system versus a two lamp 18 Watt LED. I also assumed a total of 100 fixtures. That kind of situation should be LED's perfect storm, but it still comes up short.

Here's the link with all of my math.

In short, after 10 years, LED never produces an ROI. LED tubes cost more than $5,200, or 27% more, than a well designed T8 system. And you know what's weird? If I do 24/7 run hours, the numbers get worse for LED! Instead of one replacement in 10 years you need 2!

Also, I didn't even include labor on the LEDs but did for the T8. So, yeah. Financially speaking, LED tubes are a huge waste of cash.

 

[Besoeker]

Sure.

Based on 12 hours a day and .15 cents per KWH T8 still wins. I assumed a two lamp 28 Watt low power ballast T8 system versus a two lamp 18 Watt LED.

You consider those to be comparable?
Just asking.

 

[TNBaer]

You consider those to be comparable?
Just asking.

I do not consider an 18 watt LED tube and a 28 Watt T8 comparable. However, many LED tube vendors use an 18 - 22 watt as a replacement. I am merely echoing their claims. I honestly think you will need a higher wattage than 18, which would make the "payback" even worse.

 

[BullsnPyrs]

Quite evidently, you are not immune from typos.


Accepted.

Not only am I not immune, I am prone to them. big fingers, little keys.

 

[Electric-Light]

I do not consider an 18 watt LED tube and a 28 Watt T8 comparable. However, many LED tube vendors use an 18 - 22 watt as a replacement. I am merely echoing their claims. I honestly think you will need a higher wattage than 18, which would make the "payback" even worse.

It's gonna have to have 127 to 150 lumens per watt to meet that claim as the system efficacy of F32T8/28W is about 100 lm/W.

You'd have to do some creative reporting, like mating fluorescent lamps with a inefficient, but semi-indirect fixture with 50-60% efficiency and comparing against direct lighting provided by LEDs without assistance of fixture optics. The outcome is that you'll get a very hard direct light that casts sharp shadows.

 

[Electric-Light]

http://assets.sylvania.com/assets/d...P XL.bc74ac49-8157-44fa-8138-461c57ffc768.pdf

52,000 @ 12hr cycle on instant start, but if you will cycle them more often, they're rated at 60,000 hrs on programmed start at 3 hr cycle.