LED light bulbs?

[Brian Ellis]

When I bought this house 11 years ago, I put CFLs (with inductive ballasts, at thet time) in the three bathrooms. I had brought these out with me and had been used in Switzerland for a short time previously (probably a year). They were rated at 220-230 V and here the nominal voltage is 240 V, usually slightly higher with peaks of 248 V, so I didn't expect them to last long. I replaced one about 2 years ago after about 10 years estimated total. The other two are still working fine, although are dimmer. I went all-CFL (modern type) about 2 years ago except for a single tungsten bulb (40 W) on the landing, because the appliqué is too small to take a CFL, totalling 17 bulbs. They all work fine, no failures.

[Evildead666]

All CFL's here.

Dim as crap when switched on, but get a lot better quickly...
Have ahd a few of them 'pop' over the years, average life is good tho...

[xortam]

I also don't care for the light off of a florescent. I find it harsh and irritating. My favorite light is halogen on a dimmer. You can get them brilliantly clean white or dim them to a warm low setting.

[Brian Ellis]

I also don't care for the light off of a florescent. I find it harsh and irritating. My favorite light is halogen on a dimmer. You can get them brilliantly clean white or dim them to a warm low setting.

Which colour of fluorescent? There is a wide range from "daylight' (5500 K) to warm (2800 K). You can now get dimmable CFLs, albeit more expensive, although the colour does not change significantly.

[Evildead666]

ooh, didn't know you could get 'dimmable' ones...

I was also wondering, if you have insufficient light, you may be susceptible to rickets.
I know this is mostly for young people growing up and such, but would the light source from CFL or LED's be sufficient to stave off rickets ?

I'm not a medical doctor, so i can only speculate, but it would be interesting to know...

[Brian Ellis]

The short answer is no. The UV radiation from CFLs is negligible and from LEDs is zero.

Careful exposure to sunlight is the best way but vitamin D3 is an alternative. However, I am against the use of vitamin supplements except for very specific medical conditions. A good balanced diet should provide all the vitamins that are required by normal humans.

[xortam]

Which colour of fluorescent? There is a wide range from "daylight' (5500 K) to warm (2800 K). You can now get dimmable CFLs, albeit more expensive, although the colour does not change significantly.

The Greenlite CFLs that I recently used are rated at 2700 K, 1100 lumens. The packaging doesn't state the color though so you have to look on their website. The package just states "Soft White". I didn't know they made dimmable florescents. They still don't compare to the versatility of a halogen bulb for color and brightness though.

I noticed on the packaging of these Greenlite CFLs that they guarantee their product for 9 years (2 years unconditional warranty). I just called them up and they're going to send me a replacement box of 4 18w spirals. I have to hand it to them that they handled the issue quickly and didn't request return of the failed product. They agreed that the cause was probably just a bad batch.

On the original subject of LED bulbs ... So far I don't see LED bulbs advertised on-line that are for use as general area lighting. The LED bulbs are targeted for task lighting and other directional lighting uses (e.g. flashlight). They also have a quite high initial cost. I think there’s still quite a lot of work to do to improve the cost and applicability of LED bulbs for household lighting.

[az]

2700k is pretty warm. The higher the color temperature, the colder the light looks (white-hot is hotter than red-hot, which we associate with the warmth of a fire etc.).

LEDs also do not put ut zero heat. In fact, they put out more heat per light than CFLs (but less than incandescents), because there are only two ways energy can leave them: Either as light, or as heat, and their efficiency determines the ratio. This efficiency is still lower for LEDs than for CFLs.

T5 fluorescent tubes are also more effective than T8s, and thinner. Modern electronic ballasts (which aren't ballasts, but switchmode power supplies) "flicker" at 50-100 kHz, faster than anyone could detect, and fast enough that their light output doesn't decay noticeably between cycles.

Cheap (or old) fluorescents have awful light because they emit light in narrow bands, not across the whole spectrum. Better fluorescent lamps have a color rendition index (CRI) of >80, the best ones >90 (though not yet available at all color temperatures, only from few manufacturers, more expensive and not quite as efficient - still better than anything else, though).

There are "full spectrum" fluoros that do output UV along with the full spectrum of visible light. Their color temperature is quite high (daylight), though.

I like Halogen light the best, as well, but that's hardly efficient. A tad better than Tungsten, but LEDs and especially fluorescent lamps are in a completely different league. Tungsten lamps are actually heating fixtures that get so hot that they start to glow (~2% of the energy used is emitted as light, the rest as heat. With CFLs, that changes to ~8%, LED lighting is somewhere in between).

[Mehen]

Update: my uncle bought us some CFL's he found on sale a few months ago. I'm using one in my bedroom now, took about a month to get used to it (and I'm still not 100% satisfied), but its not bad.

I was going through bulbs like crazy before b/c its in a ceiling fan - the rattling would break the filament pretty easy - I can't see myself going back now. I'm still thinking I might try a LED bulb if the good ones come down further in cost.

[az]

BTW, you can save a bit using Halogen bulbs instead of incandescent, if you don't like/want fluorescents.

[Claymonkey]

ever slightly off topic but a few months ago I bought the LED conversion bulb for my old MAG light. It was one of the first ones and honestly still using the original bulb (the spare is still in the foam wrap in the spring). It work AWESOME but honestly the whiteness of it is even more dead than a flourescent. It's very bright though and the MAG reflects the light just as if it was the original bulb.

[Dr Mordrid]

I have a 30 LED battery powered work light that you dare not look at directly