Major Lighting Types: To provide detailed information on the hundreds of different types and brands of lighting would be far too large a task. Instead, here are some common-sense ways to evaluate lighting upgrades, as well as an outline of the major categories of lighting and their improvements in energy efficiency over the last few years.

A lighting product or ‘luminaire’ is a system, not a single item. The light output, quality and efficiency depend on how well all the elements of the system work together. These elements include:

• The fixture itself with a built-in reflector, which will determine the output and pattern of light
• The ballast - which may have some intelligence – dimming, communicating with building management systems etc
• The bulb or ‘lamp’, which will put out a certain number of lumens while using a certain number of watts
• Sensors which may be used for detecting daylight (i.e. less artificial light needed on bright days) or occupancy

Considerations for selecting the optimum lighting system include:

• Ceiling height
• Ceiling temperature
• The number and pattern of fixtures – which depends on:
  • the layout of the facility
  • the number and location of people working there
  • the tasks they perform
• Lamp life – which is critical because the labor cost for replacing burned out lamps is significantly greater than the cost of the lamp itself
• Installation – the design of the lighting system (which depends on activities in the facility e.g. offices, warehouse, manufacturing etc) will determine the spacing between fixtures and the cost of hanging them. This can amount to 30%+ of the initial cost

Major Lighting Categories - listed from oldest type to newest type:

• Sodium Vapor with magnetic ballasts
• Mercury Vapor with magnetic ballasts
• High Intensity Discharge - usually distinctive bell-shaped fixtures used for high ceilings, e.g. big box retailers, gymnasiums, stadiums and arenas, multi-story car parks, shopping malls etc.
  • Metal Halide – very bright (40,000 lumens) but requires 5-15 minutes to warm up, and output decays significantly over time (30-40%).
  • High Pressure Sodium - yellowish color light commonly used in parking lots
  • Both types can be retro-fitted with digital ballasts instead of magnetic coils (ballasts). This can save 20-30% of the energy consumed, or the entire fixture can be changed for a more modern fluorescent one.
• Fluorescent Lights
  • Older magnetic ballasts with T-12 lamps (1.5” diameter)
  • Newer electronic ballasts with T-8 or T-5 lamps (1” and 5/8” diameters)
    • Standard Frequency electronic ballasts
    • High Frequency electronic ballasts designed primarily for dimming
• Low voltage lighting & LED lighting are very energy-efficient but are only suitable currently for specialized applications