Light Pollution Calculator — Formula
## How to Calculate Light Pollution
Light pollution is wasted light that shines upward or sideways instead of illuminating the intended area.
### Formula
**Wasted Lumens = Fixtures * Lumens * Uplight %**
**Wasted Energy = Total Energy * Uplight %**
### Types of Light Pollution
- **Skyglow**: Brightening of the night sky over populated areas
- **Glare**: Excessive brightness causing visual discomfort
- **Light trespass**: Light falling where not needed
- **Clutter**: Excessive groupings of light sources
Fully shielded fixtures eliminate uplight and reduce waste by 30-60%.
Light pollution is wasted light that shines upward or sideways instead of illuminating the intended area.
### Formula
**Wasted Lumens = Fixtures * Lumens * Uplight %**
**Wasted Energy = Total Energy * Uplight %**
### Types of Light Pollution
- **Skyglow**: Brightening of the night sky over populated areas
- **Glare**: Excessive brightness causing visual discomfort
- **Light trespass**: Light falling where not needed
- **Clutter**: Excessive groupings of light sources
Fully shielded fixtures eliminate uplight and reduce waste by 30-60%.
Exemplo Resolvido
10 fixtures at 4,000 lumens each, 30% uplight, 50W each, running 10 hours/night at $0.15/kWh.
- Wasted lumens: 10 * 4,000 * 30% = 12,000 lumens
- Annual energy: 10 * 50 * 10 * 365 / 1,000 = 1,825 kWh
- Wasted energy: 1,825 * 30% = 548 kWh
- Wasted cost: 548 * $0.15 = $82/year