Rosemont Copper Light Pollution Mitigation Project

This television commercial, produced by Rosemont Copper, features Monrad Engineering Inc.

For decades, Monrad Engineering, Inc. and its partner firm, Benya Lighting Design, have provided expertise in the application of outdoor lighting systems in environmentally and astronomically sensitive locales.  Our work includes  shielding considerations, adaptive controls, spectral content selection, glare control, and lighting ordinance compliance activities to minimize spill light, glare, and sky-glow effects.

As a part of our work for Rosemont Copper, we created the renderings (below) which contrast the difference between a well-focused optical system and a standard approach, which creates excessive sky glow from spill light.

In this simulation, the object in the foreground replicates a waste rock dump area with a twenty foot wall placed in the background to help show spill light.  Excessive sky glow above the wall can also be seen.

Standard approach demonstrates spill light
in background and excessive sky glow above.

Focused lighting system with high performance optics illuminates only the simulated waste rock dump area.

Beam shaping and light level tuning to suit the various mine tasks, such as conveyors, grinders, tanks, etc., provides maximum lighting efficacy while minimizing energy use and adverse environmental effects.

The technology of LED also permits “spectral tuning” and specific choices can be made relative to spectral content. For the Rosemont Project, two such specific light sources (Narrow Band Amber and 495nm filtered/2905K, shown in the graphs below) represent most of the lighting for this demanding location.

Narrow Band Amber LED luminaire

(Spectral graph as measured by Monrad Engineering staff)

2905K LED luminaire with
Hoya 495nm long-pass optical glass filter
(Spectral graph as measured by Monrad Engineering staff)