Light Pollution Calculator
Calculate the environmental impact of outdoor lighting, sky glow contribution, and energy waste.
Outdoor Lighting
8 hours
Light Characteristics
Location
19 (higher = darker sky)
Bortle Class
6
Bright suburban sky
~1,000 stars visible
Light Output
21,000
Total Lumens
21,000
Sky Glow Lumens
Shielding Effectiveness0%
Energy & Cost
876
kWh/Year
$105
Annual Cost
806
lbs CO2/yr
Wildlife Impact
Insects (attraction/death)100%
Migratory Birds84%
Sea Turtles80%
Bats35%
Relative impact score based on light intensity, color, and shielding.
Recommendations
Install fully shielded (full cutoff) fixtures
Switch to warm-colored LEDs (2700K or less)
Use timers or motion sensors to reduce operating hours
Consider reducing the number of outdoor lights
Use lower wattage bulbs - often sufficient for safety
Dark Sky Tips
Use only what you need: More light does not equal more safety
Point lights down: Fully shielded fixtures prevent sky glow
Use warm colors: 2700K or warmer reduces ecological impact
Use timers/sensors: Light only when and where needed