Energy efficient downlights

Sonnenblumen

Stoner wrote:

JimiMac

the fittings you are looking at are fine. Note that nothing is as bright as a 12V 50W halogen. Personally I'd stick with GU10 CFL lamps, the are a little bit longer then an LED or Halogen lamp, but if you are going for straight down downlights in a recessed ceiling you should be fine. It's true that the mega man fittings are not great. I've seen people buy them and keep the lamp and lamp holder and buying a different fitting/body.

Some of the actual fittings from loweleds are great value for money, they have slightly different fittings with nice finishes (I have some of their nickel coated fittings in my house)

It comes down to price and what you want to do. The CFLs typically wont dim, (however someone (sorry I cant remember who, might have been CJHaughy) produced dimmable CFL lamps from megaman they had four step dimming)

LEDS are nice for colour change, but there are some nice warm CFL colours available,
CFLs take time to warm up, this can be a pain, the LEDs light up like an old light bulb.

I don't know if LEDs will be the only type of light available in a few years. The thing is they keep creeping up in energy consumption, 1W 3W now the one you are looking at is 6W, the CFLs are 7 W and 9W the consumption savings are being eroded IMO. And the CFLs keep getting better with their working hours expectancy.

The initial cost of all these fittings is very high, I would not spend 36 euro per fitting for something that is said to be mainstream in a year, if that the case they will be 12 euro next year.
I have to admit I have not seen the 6W LED in action, I'm going to get a sample in next week, and I'll let you know how it compares (I have many types at home and I put them up one beside the other, this is still the best way to compare lamps, particularly if there is a woman involved in the selection)

Nothing stands still, it's part of evolution or R&D process, you know, things getting better and more efficient. Your views are full of contradictions, eg CFL's take about 1 minute to reach full output, most are faster. CFLs are energy efficient lamps not accelerated light units, and the cost for a 15W with an equivalent light output of 70-75 W makes patent sense from a cost perspective. LEDs though energy user, are not mainstream lighting (except bill boards) and as such given their low light output levels are very limited in terms of application. On the + side they use very little electricity most < 1 or 3W. 6 W is an exception even so a very low energy usage.

Your comparison test is also a bit silly because how can you compare LEDs with CFLs with Incadescent with Halogen with metal halide etc etc? I mean would you compare cars with tractors with trucks to decide on a mode of transport. Anyways its your way but IMO its a nonsensical comparitive test.

There are many options but first you must consider the application because comparing lux level will eliminate some. Running costs or longevity might be another criteria, GU10s have a relatively short life but yet are still used extensively throughout houses even in hard to reach places like soffit boards. Only an idiot would fit such lamps in those places and how does the customer go about replacements??

Finally if you prefer to save potentially € 20 (no real proof either) by waiting a year or alternatively install an inferior fitting, well sorry but that really takes the biscuit for madness.

Assessing lamps is only part of the equation, but I do see an awful lot of poorly installed crap cheap and nasty fittings.

wasim21k

i got mine in B&Q, and they are lovely and in offer 3 for 14€:D

Stoner

Sonnenblumen wrote:

Your comparison test is also a bit silly because how can you compare LEDs with CFLs with Incadescent with Halogen with metal halide etc etc? I mean would you compare cars with tractors with trucks to decide on a mode of transport. Anyways its your way but IMO its a nonsensical comparitive test.
.

I have used and continue to use many types of lamps in both designs and installations, I did a comparison on these lamps as people ask about them from a DIY point of view, they want a straight lamp for lamp replacement. IMO LEDS can't do this yet and CFLs can.

The lux level input from a 50Watt 220Volt halogen and a 50Watt 12Volt halogen lamp are different, the 12Volt unit is far "brighter". Therefore discussing Wattage as an indication of levels of light is not accurate, the levels of light/Lux along with other personal considerations is a more accurate way to approach this.

We use LEDs for emergency lighting and Exit signage and they are very good, they are also great for signage and display.

True my post rambled, point taken, but I stand over its general meaning, this is a DIY question so discussing how good LEDS are for emergency, exit, and signage and to some degree decorative lighting has little value here, people are discussing using LEDs as a direct change to halogen lights, it is my opinion that CFLs are the only real low energy recessed spot light solution at the moment, sure the warm up time is a pain but I pointed that out to people.

Regarding my comparisons, your very well put point applies, but people here are discussing using these different types of lamps (or as you put it tractors, cars etc) for the one application, I commented on this application alone from a DIY capacity.
The thing is some people will put up with lower light levels to save money, some can't stand the warm up time for CFLs, some insist on being able to dim their lights, some don't like warm or cold light, some want their room as bright as possible.
There are many reasons over and above efficiency that form a part of the decision when choosing a lamp, I guess these issues led to some of the contradictions in my post.
Many times in a large development various light fittings with differing lamps are installed by electricians in a mock up environment located in the actual installation site, the interior designer, architect, consultant engineer, client etc. will assess this fitting in place and working and consider the switching methods, aesthetics etc.
My point being that the choice of light fitting and lamp is often made by viewing the light fitting/lamp in its intended environment, as the environment has a huge impact on the final light level and ambience created by the fitting.

I know enough from experience in working in R&D to know that nothing stands still, that’s why I use "yet" and "at the moment"
My knowledge of lighting is not limited to my "experiment" regardless of what you may or may not have assumed about me. Most people here IMO are interested in DIY and what to use in their living room when they get in from a days work.

10-10-20

LED's are going to make the jump from their pigeon-holed 'background' or highly specific applications and into the main-stream quite soon.
Part of the limiting-factor with LED's has been the light intensity per given area and this has been mainly overcome in the newer Luxeons/Cree mounted stars.

I have 3 Seoul P4's sitting on a heatsink on my bench at home and the light output from these devices at 12v & 700mA is unbelievable. The limiting factors are three-fold - the heat dissipation (approx 12w); the blue tint which is still prevalent in the center of the beam; and the power supply and current limitation design (240v AC to 12v DC @ a limited current). Other than these considerations, I have the guts of a working downlighter capable of replacing a 50w GU10.

Don't cast LED's aside!

Stoner

I'd never do that, between these posts I've just received 600 number 5mm
T1-3/4 Clear infrared LEDS for a couple of lamps I'm making myself, a decent coincidence.

10-10-20

Jasus - somebody'd going doing some night-time peepin!

Stoner

yeah, but not me !!! it's for a friend of mine, honest!;)

10-10-20

Just out of interest, what enclosure are you going to house these in and where did you get it? I was thinking about retrofitting basic light fittings from low-cost sources but this can be tricky. Any thoughts?

Stoner

last time I looked, www.besthongkong.com had empty MR16 lamp holders that you can connect your own array of LEDs too.

I am using mine to help with night vision photograhs, I have a 35 LED array in a hex shape design on my home PC, I am simply going to build each light on an 18 x 20 circuit board, and fit it into an eveready torch (about €10 c/w battery), so I'll have the battery and switch etc I'll fix on a connection to allow a 220V in PSU too.

I've copied some other guys array design TBH. I'll forward you the link if you want.

10-10-20

That website is all over the place. I can barely make head-nor-tail of it. I purchase through the German supply chains and they seem to be quite similar to this one. I didn't compare cost though.
Out of interest, send on the link for the flash-light!

I replaced a halogen tube in a vehicle worklamp with an array of 27 standard white superflux leds recently. The output is usable but if I was doing it again I'd use the 4-chip superfluxes at 9 lumens each.

faroutthere

So!..........
After reading all that I still cant decide on cfl or led.
actually are led dimmable?? that might just swing my decision.
Otherwise next to post wins!

Stoner

both CFL and LEDs are dimmable, but its not really that simple, the CFLs dimmable ones are a longer lamp, and you'll need the correct drivers to dim LEDs,

Just make sure you have GU10 lamp holders, buy one of each type of lamp and make your own mind up, it's the best way TBH.

Best of luck with it.

karltimber

Hi Stoner

after reading this thread - only realised it was from 2007 - has much changed wrt lec v cfl ?

I have 30 odd 220v 50w gu10's and wanted to change to a more energy efficient bulb for the coming winter. 15 are only ever on a one time.

any newer opinions on which to go for - led or cfl - try both first ??

thanks

K

Stoner

yes there have been some big changes. CFLs now come in two dimmable ranges, one stepped dimmer and one that has a more uniform dimming system. I don't think either one is great TBH.

LEDs have improved in output, they have more punch, but there are still issues with the spread of light IMO, note there are a number of posters with a special interest in LEDs here, consistantly new lamps are talked up and they do imporve but they are still not as "bright" as an 11W CFL IMHO.

I'd go for a mix, where you can get away with it use LEDs there are some online suppliers named in the sticky on the main electrical page. For areas where you want the most light use CFLs. You are lucky in that you have 50W GU10, not a great lamp IMO so at least you wont have to compare with 12V 50W lamps (a far "brighter" lamp) in the exchange.

The LEDS are better for the environment and the elctrical grid, they will work very well where you want to light a picture or an area where you have a good few spots (or if you don't mind shadows), try the CFLs where you want a more uniform light (and don't mind the warm up) its the warm up time that kills their new dimmable lamp IMO, when you turn the light on you have to wait for it to heat up, so you have to either wait there for it to heat up, or return to it to adjust the dimmer.

A mix would be the best option IMO

faroutthere

well,
I went with the cfl . And to be perfectly honest we are very happy with them . dont find them too white or anything. thanks for the advise stoner