Overview: Lighting typically consumes 25-35% of the total energy used in a facility, so it’s well worth looking for energy efficiencies in this area. Older lighting fixtures (see Lighting Types) are grossly energy-inefficient and prone to substantial decay in light output over time, which means you probably have 30-40% less light now than you did when they were installed.

Productivity: Replacing older fixtures can yield significant energy savings as well as harder-to-measure, but nonetheless real, improvements in productivity. Often you don’t realize how bad the light has become until new lighting is installed. If you haven’t replaced your lights in the last 3 years or so, recent advances in lighting technology make it well worth your while revisiting the issue.

No single fixture or lighting system suits every purpose. As a result, the lighting industry has several hundred manufacturers of ballasts, bulbs, fixtures and controls distributing their products through a myriad of architects, engineers, lighting designers and lighting distributors.

Lighting Efficiency: The quality of light enjoyed by workers is critical. In a perfect world, you want:

• The best quantity and quality of light for the task at hand - delivered to the work surface
• The lowest total cost of ownership, which doesn’t necessarily mean the lowest initial cost

Total Cost of Ownership: Just like buying a car, initial cost is only part of the equation. Since ceiling heights can vary widely, often requiring use of a elevated platform, labor costs to replace burned-out lamps and ballasts can be substantial. The main components of TCO are:

• Initial cost: Typically 4-6% of annual cost of operation
• Energy efficiency: Especially dimmability – 85-90% of annual cost of operation
• Maintenance: Labor can be 8-12% of annual cost of operation
  • Lamp longevity: Ceiling temperature-dependent
  • Ballast longevity: Ceiling temperature-dependent
• A/C Load: Lower temperature lamps will reduce A/C load
• Disposal Costs: Certain lamps (e.g. HID) require specialized disposal

Payback: The good news is that, in many instances, it is possible to improve both light quality and energy consumption simultaneously, with rapid paybacks - frequently less than 2 years. Even better, in some states there are substantial incentives (grants and loans) that can reduce the capital cost and accelerate paybacks significantly.