[Chaos-l] LED lamps replacing LPS and effect on light pollution [was: Thoughts...]

[Jon Stewart-Taylor]

On Aug 29, 2011, at 8:43 PM, walter fowler wrote:

> [...] The real solution to light pollution was enunciated by Jim  
> Morrison:  "When the music's over ...  turn out the lights."

The 5 rules of Only Good Lighting (tm):

1) Only illuminate it IF it needs to be lighted.
2) Only illuminate it WHEN it needs to be lighted.
3) Only illuminate it  AS MUCH as it needs to be lighted.
4) Only Illuminate it FROM ABOVE.
5) Only illuminate IT, nothing near it.

Number 1 makes more difference than anything else, regardless of the  
type of light.

For number 2, LEDs can be turned on and off quickly and efficiently,   
and so might encourage reduced duration of lighting.

Numbers 3-5 could implemented by using new LED fixtures.  Retrofitting  
LEDs lamps into existing fixtures probably won't help much.  But:

#3 could be addressed by reducing the total lumens emitted from the  
new lamps.
#4 could be encouraged due to the low weight of and reduced  
maintenance required by LEDs.
#5 could come free with the directionality of LED lamps, from  
replacing existing fixtures with full-cutoff fixtures, and as a  
byproduct of #4.

I suspect that most scientists would be perfectly happy to trade the  
mono-chromatic light dome from LPS lighting for a broad-spectrum light  
dome 1/2 the size, duration, and intensity.

I know as an amateur, i would be happy.

What i fear is an _increase_ in the intensity (fewer Watts gives more  
Lumens with LEDs), and no change in the duration of illumination or  
the type of fixtures.  A glare-bomb is still a glare-bomb, no matter  
what kind of lamp is in it.

*gets off soapbox*

J.

PS: Kinda cool idea, motion-detector/LED streetlights which are only  
on when there's a car within 10 meters or so of it, and off otherwise.

J.
-- 
Jon Stewart-Taylor:  joncst at earthlink.net
Chapel Hill Astronomy: http://www.rtpnet.org/chaos