Lighting
Lighting is vital for a colony. A colony might have a limited number of windows, so lighting would be required permanantly. Plants in greenhouses might need to be lit artificially to supplement natural light. Rovers must have headlamps for driving at night or during dust storms.
Contents
Types of lighting
Incandescent
Most lightbulbs on Earth are incandescent. Fire and stars produce light via incandescence. In an incandescent light-bulb a metal filament (Usually tungsten, the only metal that can withstand the temperatures) is heated to around 3000C. A glass bulb is fitted around the filament and the air evacuated or replaced by an inert gas, because the filament would otherwise oxidize and burn.
Fluorescent
Halogen bulbs
LED
LED are energy efficient, and produce little heat compared to incadescent, flourescent, and halogen bulbs.
BioLEDS
Uses
Illumination
The primary use of lighting is illumination of a settlement. A well-lit environment is vital for the morale and safety of the residents.
Standard illumination levels in building on Earth are
Agriculture
Most plants require more sunlight than is available on the martian surface. Dust storms can also obscure the sun for months at a time. Artificial lighting is needed to at least augment the natural light.
Health
The proper wavelengths of light are needed by humans to produce Vitamin D.
Certain lights, emulating natural sunlight, are used to treat Seasonal Affective Disorder.
Lighting levels
| Condition | Illumination | Power intensity | |
|---|---|---|---|
| ftcd | lux | W/m2 (W/ft2) | |
| Sunlight | 10000 | 107 527 | 1300 (120) |
| Full daylight | 1000 | 10 752 | 130 (12) |
| Overcast day | 100 | 1 075 | 13-18 (1,3-1,8) |
| Very dark day | 10 | 107 | |
| Twilight | 1 | 10,8 | |
| Deep twilight | 0,1 | 1,1 | |
| Full Moon | 0,01 | 0,11 | |
| Quarter moon | 0,001 | 0,011 | |
| Starlight | 0,0001 | 0,0011 | |
| Overcast night | 0,00001 | 0,00011 |
The table below provides recommended light levels from the IESNA Lighting Handbook and LPD levels from the IECC 2015
| ROOM TYPE | LIGHT LEVEL (FOOT CANDLES) | LIGHT LEVEL (LUX) | IECC 2015 LIGHTING POWER DENSITY
Watts/m2 (WATTS PER SF) |
|---|---|---|---|
| Bedroom - Dormitory | 20-30 FC | 200-300 lux | (0.38) |
| Cafeteria - Eating | 20-30 FC | 200-300 lux | (0.65) |
| Classroom - General | 30-50 FC | 300-500 lux | (1.24) |
| Conference Room | 30-50 FC | 300-500 lux | 1.23 |
| Corridor | 5-10 FC | 50-100 lux | 0.66 |
| Exhibit Space | 30-50 FC | 300-500 lux | 1.45 |
| Gymnasium - Exercise / Workout | 20-30 FC | 200-300 lux | 0.72 |
| Gymnasium - Sports / Games | 30-50 FC | 300-500 lux | 1.20 |
| Kitchen / Food Prep | 30-75 FC | 300-750 lux | 1.21 |
| Laboratory (Classroom) | 50-75 FC | 500-750 lux | 1.43 |
| Laboratory (Professional) | 75-120 FC | 750-1200 lux | 1.81 |
| Library - Stacks | 20-50 FC | 200-500 lux | 1.71 |
| Library - Reading / Studying | 30-50 FC | 300-500 lux | 1.06 |
| Loading Dock | 10-30 FC | 100-300 lux | 0.47 |
| Lobby - Office/General | 20-30 FC | 200-300 lux | 0.90 |
| Locker Room | 10-30 FC | 100-300 lux | 0.75 |
| Lounge / Breakroom | 10-30 FC | 100-300 lux | 0.73 |
| Mechanical / Electrical Room | 20-50 FC | 200-500 lux | 0.95 |
| Office - Open | 30-50 FC | 300-500 lux | 0.98 |
| Office - Private / Closed | 30-50 FC | 300-500 lux | 1.11 |
| Parking - Interior | 5-10 FC | 50-100 lux | 0.19 |
| Restroom / Toilet | 10-30 FC | 100-300 lux | 0.98 |
| Retail Sales | 20-50 FC | 200-500 lux | 1.59 |
| Stairway | 5-10 FC | 50-100 lux | 0.69 |
| Storage Room - General | 5-20 FC | 50-200 lux | 0.63 |
| Workshop | 30-75 FC | 300-750 lux | 1.59 |
Open Issues
- How much light is needed for day-to-day activity? Humans have two types of vision, color and low-light. Once the vision has adjusted to low light, the average human is able to function well in the light of the full moon, but without the ability to see in color.
- How much exposure time is needed for the skin to produce enough vitamin D?
