| Light Source |
FTL |
Mercury |
Sodium |
CFL |
LED |
| Lumens/ Watt (Source) |
60-90 |
50-65 |
65-105 |
50-70 |
91-130 |
| Lumens/ Watt (Application) |
40-60 |
25-35 |
30-55 |
30-50 |
70-90 |
| CCT |
4,000 - 5,500 |
3,000 - 4,500 |
1800 - 2500 |
3400 - 6500 |
4000 - 6500 |
| Rated Life - 50% depreciate |
4,000 Hrs |
4,000 Hrs |
4,000 Hrs |
5,000 Hrs |
>50,000 Hrs |
| Driver/ Choke Life |
10,000 Hrs |
10,000 Hrs |
10,000 Hrs |
10,000 Hrs |
>50,000 Hrs |
| Eco - Friendly |
Mercury Used |
Mercury Used |
Mercury Used |
Mercury Used |
Eco-Friendly |
| Potential for carbon - Credits |
No |
No |
No |
Yes |
Yes |
No Perfect Artificial Light Source Exists (yet)
|
Incandescent
Pros: Very cheap, great color
Cons:: Very short lifetime, poor energy efficiency
|
High Intensity Discharge
Pros: Cheap, efficient
Cons:: Poor color, long restart, short lifetime |
Fluorescent
Pros: Cheap, energy efficient
Cons:: Can not run in cold temp, difficult/costly to dim, control, Hg |
Compact Fluorescent
Pros: Energy efficient
Cons:: Poor color quality, Can not run in cold, High cost vs. Incand, Hg, Issues of safe disposal |
Halogen
Pros: Great color, focused light
Cons:: Very short lifetime, poor energy efficiency |
LED lifetime and Lumen Maintenance
- Operating under reasonable design conditions LEDS have a projected lifetime of 50,000 hours at 70% lumen maintenance
- LEDs inherently fail “gracefully” – no burn out, catastrophic failure
- Up to 100,000 hours (>11 years continuous life) can be projected