Why do We Need Dark Light?

No Light May Be Emitted Upwards into the Sky in Street Lighting and in Urban Lighting?

A lot of the outdoor lighting used at night is inefficient, overly bright, poorly targeted, improperly shielded, and in many cases, completely unnecessary. Because it spills into the sky rather than being focused on the objects and areas that people need illuminated, this light and the electricity used to create it are being wasted. 

The dark sky requirements for outdoor urban lighting products that European customers typically consider include:

1. Light pollution control: The requirement is to reduce light pollution and avoid excessive illumination, ensuring that the light only illuminates the necessary areas without leaking into the sky or other unlit areas.

2. Reflection reduction: The requirement is to minimize the reflection and scattering of light, avoiding excessive light pollution caused by light reflection in the atmosphere.

3. Dark sky protection: The requirement is to minimize upward lighting, directing the light predominantly in the horizontal direction and avoiding excessive light projection towards the sky.

“The International Dark-Sky Association recognizes and advocates for natural areas that protect true darkness. These parks ensure the protection of nocturnal species and allow scientists to carry out astronomical research. They’re also preserved for public enjoyment, because we all deserve a front row seat to the galaxy.  

When you live in a metropolis or even a modest town, it may be rare to see more than a few hundred stars each night. A few hundred twinkles may seem good enough, until you’ve seen the rings of the Milky Way light up the zenith.’ (https://mild2wildrafting.com/rafting-blog/what-is-a-dark-sky-park-and-why-you-need-to-visit-one/)

4. Energy efficiency requirements: The requirement is for lighting products to have high energy efficiency, utilizing low-power LED fixtures or other energy-saving lighting technologies to reduce energy consumption.

These requirements aim to protect nighttime air quality, astronomical observations, and the ecological environment of wildlife and plants.

We take ST52 an example.

AGC urban light ST52 post top has direct light and indirect light 2 options.

If you ask for dark sky, advise you please consider direct light.

How to choose those luminaires fulfill the requirement?

Here are our experiences on dark sky luminaires.

1. The dark sky requirement is for upward light to be less than 0.5%.

2. Indirect lighting will definitely not pass the requirement.

3. For direct lighting, it also depends on the color of the luminaire. The darker the color of the luminaire, the better it absorbs light and can meet the dark sky standards. Light-colored luminaires, such as gray, may not pass the requirement as they reflect too much light.