As an environmentalist who is tired of “politically correct” approaches and wants to directly address the issue of overpopulation rather than put around the “20% more efficient light bulbs” while the world falls apart around us, I’d wholeheartedly vote for a serious Eco-Nationalist party. I actually found this article by Googling the term hoping and praying such a platform exists.

Furthermore, LED bulbs often won’t physically fit inside the fixtures used by E27 incandescent/CFL bulbs.

CFL is available in a wide set of color temperatures, all with the same high 82 CRI (some even higher: this is the minimum for CFL): 2700K, 3000K, 3500K, 4100K, 5000K, 6500K.

LED bulbs have poor CRI: typically in the 70s. The more efficient bulbs have this low CRI.

In short: 21st Century pricing, 20th Century technology, and 19th Century efficiency. Back to the future means no future, and there is no future for the LED bulb as a replacement for general-purpose CFL and incandescent.

To succeed as a replacement for the E27 general-purpose bulb, a new type of bulb has to have ALL these characteristics:

1. Low price with a decently quick payback period.

2. Equal or higher efficiency than the best currently on the market.

3. Equal or higher color rendering index value than standard CFL: 82 CRI minimum.

4. Physical dimensions same as a standard E27 60W incandescent or not too much different.

5. A range of color temperatures from 2700K to 6500K.

6. No flicker. The current champion, CFL, uses a high-frequency drive circuit to run at minimum 10KHz., typically at 15KHz.

It is not good enough that it has just SOME of these characteristics. Nobody’s gonna buy a high-efficiency bulb with crappy 70 CRI that makes living flesh look dead, especially one that costs a fortune. Or a warm LED bulb that has decent color but poor lumens/watt efficiency.

There are LEDs and a few LED bulbs that can do one or more of the Big Five requirements - but none that can come close to meeting them all.

The ignorance of manufacturers to the needs of the vast majority of their customers has already foredoomed the LED bulb to the dustbin of history. A scrapheap full of techno-failures.

1) One aspect that isn’t really covered is longevity. I have an original Philips CFL from the late 1980’s with a huge glass exterior cover - it still works. However as CFL bulbs prices have dropped , so has the longevity. I’m changing CFL’s approximately as quickly as I changed older incandescent bulbs. perhaps it’s a case of me buying too chepaer brand of CFL’s , but my impression is that as prices have dropped , so has quality.

2) halogen lighting. 12v or mains voltage (110v or 240v) halogen lighting is very popular . The mains voltage bulbs (GU10) come in 35 or 50 watts varieties and typically these units are installed in the tens in new builds or modernisations. There are CFL bulbs in this form factor, but my experience is that the heat build up in the small area kills the CFL’s quite quickly. I have had a number of Megaman CFL GU10 bulbs last barely a couple of years. I thinks some of the super bright LED GU10 bulbs are starting to be a better alternative in this form factor

As alluded in other comments, the real application of LED bulbs in the home is to replace halogen spotlights, not as a replacement for traditional incandescen bulbs - which are best replaced by CFLs as Ross’s analysis shows. Many modern houses have dozens of halogen spotlights - I counted 45% of the light-fittings in my house need spotlight bulbs rather than the traditional pear-shaped bulb. Because of the physics of existing CFLs, they cannot be made very small, and therefore may never make very good spots. There are a few spot-light shaped CFLs on the market now but a) they are rubbish at making a spotlight beam and b) the output profile of the CFL will mean that they will always substantially reduce efficiency when put inside a small spotlight reflector - a lot of light is inevitably reflected back into the bulb, just heating it up. In contrast LEDs are designed to shine all the light out in more or less one direction, and being very small, it is easy to shape the beam with a curved mirror into almost any beam shape you want - narrow or wide. I dont know why people keep comparing LEDs with CFLs - the clear market advantage is for a replacement of halogen spots. Here are the figures. I take for reference a typical 35W MR16 halogen spot (http://www.1000bulbs.com/product/5060/MR16CG-GU1035.html)

And of course you have that additional glowing feeling inside that you did a little bit to save the planet! Furthermore, in the UK most of Europe where electricity prices are already upwards of $0.17/kWh the savings are even more dramatic. Note however that LEDs will get dimmer over their lifetime, whereas halogens will maintain a much more constant output.

Another comment - if you go into a lighting shop today, you will find many fancy domestic lights that have 6 or more small halogen bulbs in them - for “artistic effect” - they look great, but you could never achieve the same with a CFL. However you could in principle achieve something similar with LEDs. Though I have yet to see such products appearing in my local shops, it is only a matter of time - once manufacturers can agree a standard.

Krisbow (China) has some downlighting that uses high intensity LEDs which only use 3W to produce a decent beam.

PT. Iron Global Indonesia produces LED street lights,flood lights and even tube lights. The tube LED lights (which are made to look like the regular ones) are about $65 each, but the cost savings over the lifetime of the bulb compared to a $6 TL36W tube is substantial enough that within 1.59 years, the bulb has paid for itself (given Indonesian prices for energy). If you want the spreadsheet comparison, email me and I’ll send it to you. That means that, over the expected lifespan of the LED tube (about 50,000 hours, which would be about 11.4 years given usage of 12 hours/day), you’d end up saving about $370. Factor in the cost of not having to replace starters and ballasts (which you’d have to replace probably once or twice in 10 years), and you have an even larger savings. (Figures converted from Rupiahs to Dollars and assumed energy savings are based on Indonesian energy prices.)

You did manage to mention in your response to the CrimsonSnapper that semiconductors require hazardous substances, something that hasn’t been much explored as to its impact on the environment. You failed, however, to mention the large use of electricity and water necessary to manufacture LEDs. (Playing devil’s advocate.)

You could also compare the relative safety of dumping LEDs into a landfill compared to the threat of CFLs and other gas-based lights.

Please also don’t forget that the listed wattage of a light bulb doesn’t actually represent the total usage of the bulb. Components within tubes, CFLs and LEDs consume an additional amount of electricity.

Thank you!

http://www.motiflighting.com/images/simples/100804_Motif_Retail%20WP.pdf

Firstly, thanks for reading the blog!

The motivation behind the post was to put some perspective behind the claims of a household LED manufacturer. I chose to compare the light bulbs from this particular manufacturer since they were putting out a lot of marketing in the blogosphere about how much cheaper their new LED light bulb was, whilst selling a CFL that out-performed it financially. I started crunching the numbers out of personal interest at first, since I’m always looking to save energy at home and was hopeful that the LED bulbs might be approaching a price watershed. I was genuinely surprised and disappointed by the financial differences - perhaps that disappointment showing a little too much in the tone of my post!

To be clear, my company is not in the household lighting marketplace, so this was not a dig at a competitor. We’re also looking at LED in the long term if we can make it work better for the kinds of applications which our clients demand. But at the moment they are not only too expensive but don’t deliver the right light quality either.

For ‘high traffic, safety-driven work environments’ as you say, the raw energy savings from our luminaires and LED sources are usually roughly the same - the last product we came head to head with still had a lower lumens per Watt then Eluma though. Not only that, but LED lighting as a point source is very directional, which in a work environment leads to a lot of scalloping and glare which can make conditions more dangerous and colour rendering worse.

To circumvent this problem, an LED luminaire would need a substantial diffuser in order to spread the light better, but this would then add further losses into the system, reducing the efficiency further. Therefore the raw LED light would have to be a lot more efficient than a T5 lamp, rather than just fractionally or worse. By contrast, T5 luminaires like Eluma can use highly reflective materials to shape the light better (it’s not just clever dimming controls! )

This is one of the main problems with the LED bulb featured in this analysis. It features a diffuser in order to spread the light better, but ends up creating far less light as a result. You make a good point about warm-up times for CFL bulbs if overstated - my CFLs at home certainly don’t leave me scrabbling around in the dark with my daughter whilst they warm up (although your single-mum-block-of-flats scenario made me smile since my wife specialises in residential block management in Cornwall, and most of her clients throw a fit if a communal light is performing sub-optimally). However the above CFL before it warmed up would be putting out around the same amount of light as the LED bulb at full brightness! The challenge for LED lighting isn’t just financial, but shaping the light more effectively too.

Your halogen spotlight v LED example is a great one though. Because of the directionality of LEDs, spotlight applications are perfect right now and perform as desired, and the difference in efficiency make the payback much better.

I’m sorry if you think I’m being overly biased with this article, but LED lighting is still unavoidably in it’s infancy. It’s a fantastic technology when compared to traditional lighting, but isn’t the only new kid on the block and is currently out-performed financially and operationally by modern fluorescents in many situations. This I have no doubt will change, but that is the current state of play.