L Prize (Fail!)

Posted May 13, 2012 // Tagged as Blog // 18 Comments ↓

I have spent the last couple of weeks in San Francisco and taken the opportunity to observe the impact of the Californian ban on incandescent lamps that was implemented in January 2011. Basically it has had zero effect. Standard incandescent lamps are freely available through all retail supply outlets. I have checked corner stores, supermarkets, neighborhood hardware stores and DIY sheds all have a full range of conventional incandescent lamps. The “Energy Saving” options vary considerably. Most stores have a reasonable complement of CFLs some have halogen incandescent replacements but only on hardware store and the DIY sheds carry any LED incandescent replacements and just the DIY shed had the L prize lamp that I was very keen to get my hands on. These LED options are all selling in the range $17 to $24.
the lamp

There has been so much store set by the quality of the L prize lamp that I was very keen to get one as it seems unlikely we will get them in the UK anytime soon. The first thing that surprised me was the extent of packaging for what is supposed to be an environmentally friendly product.

L prize packaging

When first switched on I have to concede that the appearance of the light was OK in comparison to the GE Reveal lamp that it was replacing. The reveal is an incandescent with a slight blue tint.

L prize full on

GE Reveal full on

The difference to the eye was not as marked as the images appear.

As expected when dimmed things changed dramatically:

L Prize dimmed


GE Reveal Dimmed

The L prize got cooler in appearance and the perceived colour rendering became much worse casting a gloomy grey in the space. the lamp also suddenly went out about half way through the travel of the dimmer’s slider, the GE lamp dimmed right down to the minimum setting. What was really alarming was that the L prize lamp would not switch on at dimmer settings below about 70%. This was a serious problem in this location where three way switching was installed.

Really I am somewhat disappointed in a product that cost me $19.75 and does not work reliably at less than full power even when it claims to be dimable. Solutions such as this must be made fully compatible with existing wiring infrastructure.

Another point about the massive cost for these lamps is whether or not the claimed savings are realistic in domestic use. How many people will be using the same lighting after 22 years? How many will still be living in the same house or apartment? At 58 years old I have to question whether I will still be alive to realise these claimed savings! It really is not good enough that the best of these lamp replacement products should be priced so high and fail to meet reasonable performance expectations that at least they do not risk leaving people in darkness! I do feel that the general lamp buying public are being conned into overspending for overcomplicated and ineffective products.

This page from EarthLed shows a dissection of the L prize lamp. It really does question the holistic sustainability of replacing such an elegantly simple device as the traditional incandescent lamp with something that requires computing power that would shame the flight computers of the Mercury and Gemini space programmes and has more electronic components than a transistor radio! All in all the resources used to make this thing are truly excessive for the required functionality.

Kevan Shaw May 12, 2012

It has been brought to my attention that this is in fact not the L prize lamp but Philips lighting own knock -off! I bought this in a Home Depot and asked the staff if this was an L prize lamps and I was told that this is the version that Philips actually sell. It is made in China and it does not have the same design as the L prize however it is what is commonly available. I understand that the real L prize is available at around $70 only from specialist retailers that are predominantly on line. I suppose you can see the reason the Home Depot and similar retailers will not stock a $70 lamp when the predominant market price for LED replacements is already at an extortionate $20+. My main point stands that none of these LED replacement lamps are really fit for purpose.


Kevan Shaw December 27, 2012

18 Responses

  1. peter

    May 16th, 2012 at 14:27

    Good point about dimming effect :
    Unsurprisingly it mirrors CFL problems since these LED types use similar coating (phosphorescent ) to spread the light.

    And dimming after all is also an “energy saving” that ban proponents welcome.

    Dimming and other problems were also highlighted in the official committee test review and designated test lab reports
    “All about the new Philips LED Bulb, and how it won the L-Prize”

  2. Kevan Shaw

    May 16th, 2012 at 15:24

    Apparently what I have is not the L Prize lamps but a confusing look-alike also sold by Philips! This one is a Chinese made version, The L prize version itself is ” Assembled in the USA” . So Philips are knocking off their own products! The L Prize version is obviously too expensive for normal retail and is going out through specialists such as EarthLed!

  3. peter

    May 16th, 2012 at 16:14

    K, re your comment, and purchase of Chinese version from DIY place for $19.75,

    So I wonder if Philips are using L Prize specs highlighted in reviews (eg lumen per watt efficiency)
    and the “kudos” from winning the L Prize,
    to push sales of cheaper inferior Chinese versions in ordinary stores for Joe Public who is assumed not to question quality and specs?

    No! Never! ūüėČ

  4. Tim

    July 22nd, 2012 at 18:49

    That Philips bulb you bought is the cheaper bulb they offer. They have offered it for a year, it is essentially “last year’s model”.

    The L Prize bulb is much more expensive. It is not just the US made version of this, it is designed differently. And it dims very well.

    Although I’m sure you would be able to find complaints with it, at very low dim levels it does change color unexpectedly. However, these dim levels are below the level at which incandescents dim reliably also.

    LED bulbs do not get warmer (redder) as they dim, so your test would have failed with an L Prize bulb no matter what. Honestly I don’t like this “mood lighting” aspect of LED bulbs, but there is at least one company working on an LED bulb that will get warmer as it dims to satisfy people who wish to have this.

    Yes, Peter, Philips is using the marketing from their higher end bulb to also sell lower end bulbs. Who wouldn’t? You do see cheaper GE bulbs next to their Reveals, right?

  5. Kevan Shaw

    July 23rd, 2012 at 06:53

    Tim, I checked out every retail opportunity that people normally use to buy lamps and this was the only Philips lamp that was stocked and sold. I agree that this is not the actual L prize lamp but it is best available product from Philips who are using the L prize as their sales pitch. Have you managed to buy a real L prize lamp retail? If so where?

    As for dimming the lamp, the failure to dim properly and to restart at low dimmer settings are the major problems. Colour change on dimming is another issue. If the same apparent colour was maintained that would be acceptable. Warming up as the lamp dims is desirable and there are LED products in the professional market that can and do achieve that however not in an A lamp form factor. The required complexity of electronic design means that this is not a realistic prospect and certainly not in the retail lamp replacement market.

  6. Consumer tests 1 « Greenwashing Lamps

    July 26th, 2012 at 14:41

    […] Colour temperature: only one appears to have an incandescent-like CCT – the 12W Philips MyAmbiance at 2643 Kelvin, followed by their 9W MyAmbiance bulb at 2804 K. All other LEDs seem way too cold to visually pass for incandescent replacements, and all in the wrong order too: dimmer light should always be more red (lower CCT), not more blue as that is opposite to what happens with incandescent light when you dim it or use lower wattage.¬†(Kevan Shaw recently tried a 12W¬†MyAmbiance¬†and was not at all impressed with its¬†dimming behaviour.) […]

  7. […] Again at ridiculous prices, with more or less appalling light colour, suboptimal colour rendition, dimming problems, heat sensitivity and a promised life that still remains to be […]

  8. More LED issues « Greenwashing Lamps

    August 11th, 2012 at 17:36

    […] Yesterday,¬†finally got to see the famous L-Prize winning 12 W¬†Philips MyAmbiance¬†LED bulb for myself (available only in a few select stores in Sweden).¬†It was¬†very¬†heavy. Probably because of all the electronics inside and the amount of metal needed for heat sink. But¬†I have to say the light looked very incandescent-like from just looking at the lit bulb there in the store, and bright without being glaring. But as I didn’t feel like spending¬†‚ā¨70¬†(!) on a lamp I’m not sure I’ll like at home, or how long it will last, I have yet to see how the light looks in a home environment without all the lit surrounding lamps of all sorts. Maybe I’ll buy one later anyway just to satisfy my curiosity. Meanwhile, here is lighting designer Kevan Shaw’s impression:¬†L-Prize Fail! […]

  9. Alan Drake

    August 12th, 2012 at 02:26

    You did *NOT* get an L-Prize bulb – but an earlier generation that lead to the L-Price bulb.

    Color rendering (CRI = 92) for the L-Prize is significantly better,

    Your version uses a deep blue LED to excite an orange phospher. The L-Prize uses both red & blue LEDs to excite a yellow phospher.

    And you got other stuff wrong as well.

    The L-Prize bulbs do not fail – stress testing that caused 15 CFLs to fail did not take down one L-Prize bulb.

    After 18,000 hours lumen maintenance is just over 100%

    Simply the best bulb in the world !

    940 lumens for 9.7 watts

  10. Kevan Shaw

    August 12th, 2012 at 09:11


    What I got was the lamp that is readily available in USA retail stores and is being promoted as the L prize lamp. I agree that this is not the lamp that won the L prize, it seems to be an inferior Chinese product branded by Philips Lighting. This lamp is not a predecessor to the L prize competition lamp or the subsequent product which is still different from the lamp that was tested for the competition. It is a more recent product being sold by Philips to capitalise on the result of the competition!

    As for the best bulb in the world I still do not thing that the incandescent lamp is surpassed for effectiveness, appearance, colour rendering, dimmability, minimal use of resources in manufacture and benign materials for end of life disposal. All LED and CFL lamps continue to fail on all these factors, succeeding only in delivering more measurable lumens for the same electrical input, and in some situations lasting considerably longer before needing replacement.


  11. […] have electromagnetic compatibility (EMC) issues and .¬†Most are not dimmable, and the ones that are do not dim well. (The reason they’re dimmable is just to make them work with existing installed dimmers […]

  12. Paul

    August 25th, 2012 at 22:32

    About the comment,
    incandescent lamp is not surpassed for effectiveness

    “They impose what seems Efficient, they forget what is Effective”


  13. More on LED « Greenwashing Lamps

    August 27th, 2012 at 18:02

    […] as noticed by¬†Save The Bulb, even the top of the cream L-Prize LED bulb doesn’t dim very well. (I believe the reason some […]

  14. Warm-White LED Review « Greenwashing Lamps

    September 14th, 2012 at 12:00

    […] This week I bought two LED lamps. I picked the ones that looked best in each shop, to see how they would look in a home environment. First up is the older and less effective sibling of the L Prize lamp (previously reviewed by SaveTheBulb): […]

  15. Jeff

    December 26th, 2012 at 22:59

    So, despite several people pointing out that this is not an L-prize bulb, you haven’t seen fit to correct your original review in the 8 months since you posted it. It seems you’re rather more concerned with pushing your preconceived agenda than reporting facts…

  16. Kevan Shaw

    December 27th, 2012 at 10:40

    Mea Culpa. I have been aware of this for some time however I did not get around to updating the post. I think you will find I have now provided an update. As a matter of interest do you actually have an L prize lamp, if so did you buy it, if you did where and what did you pay? If not please feel free to send it to me and I will do a full report on it. As I am in Europe we have not even been shown these products and they will never come to market here. Philips don’t even bother selling the knock-off version just a fairly straight forward LED replacement lamp that looks like all the others.

  17. peter

    January 2nd, 2013 at 19:33

    Re Alan / Jeff comments “that’s not the L-prize bulb”

    Well, since you seem to have missed the earlier comment here about that….

    About the L-prize bulb,
    and yes, it does have several issues as per Government testing, released on Freedom of Information basis

    ‚ÄúAll about the new Philips LED Bulb, and how it won the L-Prize‚ÄĚ
    There are also some updates you can search for

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