GU10 technology
OK, traditional GU10 lamps have several drawbacks. They give off tremendous amounts of heat, which makes them unsuitable for mounting where insulation is present. The light they produce is very narrow. Many lamps dont give off light at more than 60 degrees. Hence the light is very focused and you need a lot of lights to light a small area, or there are a lot of shadows. Stand under these lights and you can feel the heat and the glare too, it is uncomfortable to work under.
Alternative one: LEDs
So lighting manufacturers have been working on alternative methods of compact downlighting. The easiest to manufacture, and the first to come about was the LED GU10. This is a standard size GU10 lamp, with a cluster of LEDs in it. A typical cluster is less than 2 watts, one twenty-fifth the energy used by a 50 watt GU10. LEDs dont get hot, they are cool to touch when in use. They will also fit any standard GU10 fitting. However, LEDs have numerous drawbacks.
1. Light rendition: The light produced by LEDs is a pure colour and is no good for any practical use. I purchased a "white" LED lamp, however, I was less than impessed by its rendition of white. It looks very blue. LED lamps by their nature only produce a VERY limited spectrum of light. Imagine shining a red light on a blue surface. Can you see the blue? No, it appears black due to there being no blue light to reflect off it. Now imagine shining a blue light around your room. Most of the surfaces wont appear the correct colour. This is what happens with white LEDs. Even putting my hand in front of the lamp, it was dimly lit. I think maybe an RGB light might produce a better light for general use, since it gives out red, green and blue, instead of just blue.
2. Beam width: The beam width is very narrow, more so than with halogen GU10s. LEDs are very directional, and I cant help thinking "why not mount them on a curved surface?"
3. Dimming: Not that you'd want to, but its worth a mention, LED lamps cannot be dimmed (or at least its not recommended).
4. Brightness: Finally, LEDs are still not bright enough for general use.
My overall opinion of LED lamps: Still a developing technology, with a long way to go before they are suitable for general lighting use.
Alternative two: CFLs
A more recent development, compact fluorescent GU10 lamps are, in my opinion, the way forward in the near future. Unfortunately, it is impossible to cram a fluorescent tube AND its ballast/electronics into a standard GU10 lamp. CFL versions, therefore are 2cm longer. They will fit most standard fittings, but will stick out of the fitting by 2cm. Two standard wattages are available, 9 watt and 11 watt. The 9 watt version was a more than adequate replacement for a 50 watt halogen.
Thankfully, special fittings are available for these CFL lights. TLC direct is one supplier (click)
And they will fit downlighters with a flylead and retaining ring, as the depth is variable with these.
The benefits of CFLs are numerous:
Better colour rendition: they give off a balanced white light, similar to daylight, which is ideal for working environments. I changed one light in my bathroom to a CFL, and left the other two as standard halogens. I noted that after looking at the CFL end of the room for 5 mins, then looking back at the halogen end, the halogen light looked very orangey, almost dirty. The CFL light is much cleaner. In time, more shades of CFL will become available, as shades of fluorescent tubes are.
Better beam width: the light is spread over a bigger distance. I have fitted these in my bathroom, and found that I only needed 2 of these lights, whereas before i needed 3 standard halogens due to their narrow beam.
Unfortunately, CFL lamps cannot be dimmed, but the technology is emerging for switch-dimmable CFLs, which are dimmed by a succession of switch on-off signals. Its only a matter of time before this technology finds its way into GU10s.
A couple of pictures for comparison:
L-R: Megaman 9 watt CFL, Morrisons 50 watt halogen, Unbranded 1.8w LED lamp.
Final thoughts: Given EU proposals for abolishing standard filament lamps, including halogens, it makes sense to be thinking about other ways of lighting. If you really want downlighters, please consider CFLs and do your bit for the environment, and make it easier to comply with all of the building regulations.
______________________________________________________
If someone would be so kind as to either make this a sticky or put it in the wiki so people can add to it, I would be grateful. Cheers.
OK, traditional GU10 lamps have several drawbacks. They give off tremendous amounts of heat, which makes them unsuitable for mounting where insulation is present. The light they produce is very narrow. Many lamps dont give off light at more than 60 degrees. Hence the light is very focused and you need a lot of lights to light a small area, or there are a lot of shadows. Stand under these lights and you can feel the heat and the glare too, it is uncomfortable to work under.
Alternative one: LEDs
So lighting manufacturers have been working on alternative methods of compact downlighting. The easiest to manufacture, and the first to come about was the LED GU10. This is a standard size GU10 lamp, with a cluster of LEDs in it. A typical cluster is less than 2 watts, one twenty-fifth the energy used by a 50 watt GU10. LEDs dont get hot, they are cool to touch when in use. They will also fit any standard GU10 fitting. However, LEDs have numerous drawbacks.
1. Light rendition: The light produced by LEDs is a pure colour and is no good for any practical use. I purchased a "white" LED lamp, however, I was less than impessed by its rendition of white. It looks very blue. LED lamps by their nature only produce a VERY limited spectrum of light. Imagine shining a red light on a blue surface. Can you see the blue? No, it appears black due to there being no blue light to reflect off it. Now imagine shining a blue light around your room. Most of the surfaces wont appear the correct colour. This is what happens with white LEDs. Even putting my hand in front of the lamp, it was dimly lit. I think maybe an RGB light might produce a better light for general use, since it gives out red, green and blue, instead of just blue.
2. Beam width: The beam width is very narrow, more so than with halogen GU10s. LEDs are very directional, and I cant help thinking "why not mount them on a curved surface?"
3. Dimming: Not that you'd want to, but its worth a mention, LED lamps cannot be dimmed (or at least its not recommended).
4. Brightness: Finally, LEDs are still not bright enough for general use.
My overall opinion of LED lamps: Still a developing technology, with a long way to go before they are suitable for general lighting use.
Alternative two: CFLs
A more recent development, compact fluorescent GU10 lamps are, in my opinion, the way forward in the near future. Unfortunately, it is impossible to cram a fluorescent tube AND its ballast/electronics into a standard GU10 lamp. CFL versions, therefore are 2cm longer. They will fit most standard fittings, but will stick out of the fitting by 2cm. Two standard wattages are available, 9 watt and 11 watt. The 9 watt version was a more than adequate replacement for a 50 watt halogen.
Thankfully, special fittings are available for these CFL lights. TLC direct is one supplier (click)
And they will fit downlighters with a flylead and retaining ring, as the depth is variable with these.
The benefits of CFLs are numerous:
Better colour rendition: they give off a balanced white light, similar to daylight, which is ideal for working environments. I changed one light in my bathroom to a CFL, and left the other two as standard halogens. I noted that after looking at the CFL end of the room for 5 mins, then looking back at the halogen end, the halogen light looked very orangey, almost dirty. The CFL light is much cleaner. In time, more shades of CFL will become available, as shades of fluorescent tubes are.
Better beam width: the light is spread over a bigger distance. I have fitted these in my bathroom, and found that I only needed 2 of these lights, whereas before i needed 3 standard halogens due to their narrow beam.
Unfortunately, CFL lamps cannot be dimmed, but the technology is emerging for switch-dimmable CFLs, which are dimmed by a succession of switch on-off signals. Its only a matter of time before this technology finds its way into GU10s.
A couple of pictures for comparison:
L-R: Megaman 9 watt CFL, Morrisons 50 watt halogen, Unbranded 1.8w LED lamp.
Final thoughts: Given EU proposals for abolishing standard filament lamps, including halogens, it makes sense to be thinking about other ways of lighting. If you really want downlighters, please consider CFLs and do your bit for the environment, and make it easier to comply with all of the building regulations.
______________________________________________________
If someone would be so kind as to either make this a sticky or put it in the wiki so people can add to it, I would be grateful. Cheers.
