Monday, June 1, 2009

Light Pollution

I've been hitting the subject of light pollution really hard in the last two months and I'm suprised about all I have learned and tried to teach. Light pollution is the easiest form of pollution to get rid of. Just turn out a light and the problem is solved right? This is true if you want to live in darkness. I don't want to live in darkness, however I have installed interesting light fixtures on my house to set an example of what good lighting is. What is good lighting? Good lighting is lighting that doesn't spread out so my neighbors can see it. It is light that never goes into the sky to illuminate clouds and the bellies of birds. If we can all get educated on proper outdoor lighting, then the effects of light pollution won't be seen as much. There will still be a little sky glow from reflected light that hits the ground, but it won't be as bad as a light shining straight up to brighten the sky. Poorly designed lighting is the root cause of light pollution and the ignorance of "More is better." More is not better. This is a myth. If a full cut-off fixture was installed, then most of the light will be shining downward where it belongs and not to the side or up. You will find that installing a full cut-off fixture will provide downward light where it is needed and you can use a light bulb that uses less wattage because the full cut-off fixture allows all the light to shine on the subject. A full cut-off fixture will eliminate glare and wasteful light. Light that shines to the side is called "light trespass" and this affects our vision during the night. It also causes unwanted glare. We as Americans waste approximately one-billion dollars a year to illuminate clouds. Clouds should be dark at night and not glowing orange right? It's a win-win situation for everyone. Astronomers get their stars back, penny pinchers save money, and others eliminate wasteful carbon emissions.
Also, more lighting doesn't cut down on crime. For example, my neighbor has her lights running from dusk to dawn. However, the other night, her vehicle was broken in to. Did these lights help or not? The answer is no. Criminals love lights. They need lights to do their criminal work. Also, overlit areas create glare where a criminal can hide behind the glare. You won't see the criminal because you will be shielding your eyes from the glare. Ever tried driving down the road after work going west? It's hard on the eyes without a sun visor to get rid of the glare isn't it. You may not see the car in front of you if the sun is low on the horizon. Think about it.


  1. I wish more thought the way you / I do. One of the safest times in Houston was right after the Hurricane and there were no lights.

  2. It's something how that works when the lights are shut off. The technology is out there for proper lighting. It's 90% education for people to understand the benefits. Thanks for the comment.