The Natural Philosopher wrote:

Ian Stirling wrote:
Dave Fawthrop wrote:
On 20 Nov 2006 10:13:16 GMT, Ian Stirling wrote:

|Dave Fawthrop wrote:
| On Sun, 19 Nov 2006 23:12:53 +0000, Steve Firth
| wrote:
|
| |On 19 Nov 2006 14:33:10 -0800, wrote:
| |
| | Are there any commercialy-available low voltage lights which run cool?
| | Anything other than LEDs?
| |
| |LEDs do not run cool. No form of lighting runs cool. HTH.
|
| Depends what you mean by cool.
| LEDs do not run *cold*, (at ambient temperature) but run at a low lower
| temperature than incandescents, halogens etc, which in my book classes as
| *cool*
|
|They generally produce the same amount of heat for a given amount of
|light - it's just spread out more.

Just not true :-(
Almost all the power used by a 100W incandescent bulb goes into the room as
heat, only a tiny amount as light. Everyone who has burned a hand on a
lit light bulb will know that. A 22 watt energy saving bulb with
equivalent light output to a 100watt incandescent can only emit under 22
watts as heat. They only feel warm to the touch

You specifically mentioned LEDs, and my response was clearly about LEDs.
And the tubes of most CFLs hit 100C.

LEDS die at around 100C. The reason they are used increasingly in
traffic lights is energy efficiency.

Hi

Surely the primary reason for using them in traffic lights is to reduce
ongoing maintainance costs?

Steve