For most applications, lamps can be divided into four categories:
At one extreme is the incandescent lamp, the least expensive to buy, but the least efficient in converting energy to light. Its main benefits are low cost, good color rendition, and ease of installation. At the other extreme is the low pressure sodium lamp, which is fairly expensive to purchase, has no color rendering ability, but is extremely efficient at producing light. The other light sources fall between these extremes.
While efficiency alone should not be your only consideration in the selection of lamp type, it is an important characteristic. In most cases, a more efficient light source can be substituted for a less efficient source with little if any loss in task visibility or color rendition. The total annual owning and operating cost (life-cycle costing) savings achieved will help lower your electric utility bill.
| Type of Lamp | Lamp Watts | Initial Lumens | Rated Life Hours | |||
| Incandescent |
200 |
4,000 |
750 |
|||
| Fluorescent |
40.7 |
3,250 |
12-20,000 |
|||
| Mercury Vapor |
400 |
23,000 |
16-24,000 |
|||
| Self-Ballasted Mercury Vapor |
450 |
14,500 |
16,000 |
|||
| Metal Halide |
400 |
34,000 |
7.5-15,000 |
|||
| High Pressure Sodium |
400 |
50,000 |
20-24,000 |
|||
| Low Pressure Sodium |
180 |
33,000 |
18,000 |
|||
| LED | Varied |
Varied |
Varied |
And Furthermore . . .
