The difference between the yearly cost of energy for your existing system and the yearly cost of energy for the recommended system.
A measure of the light generated by one lamp. Note: Ballast factor is taken into account.
A measure of the actual lumen output for a specific lamp-ballast system relative to the full rated lumen output of the lamp being used. For example, if a lamp's standard output is 3,000 lumens, a 0.90 ballast factor will drive the lamp at 90% output, which is 2,700 lumens. A ballast factor is not a measure of energy efficiency. Although a lower ballast factor reduces lamp lumen output, it also consumes proportionally less input power. Careful selection of a lamp-ballast system with a specific ballast factor allows designers to better minimize energy use by "tuning" the lighting levels in the space.
Total lumens produced by all lamps in the fixture. Note: Ballast factor is taken into account.
The ratio of total light lumens produced to the amount of watts consumed. This is also referred to as the efficacy of the lamp/ballast system.
A fixture where the heat from the lamps can acculumlate around the lamps, such as when the lamps are enclosed or simply surrounded by the fixture on the top and sides. Most office lighting, such as parabolic troffers, fit in this category.
A fixture hanging on or below the ceiling with the lamps fully exposed to the room environment, such as a strip fixture.
A T8 is a fluorescent lamp that is tubular in shape and 8/8ths of an inch in diameter.
A T12 is a fluorescent lamp that is tubular in shape and 12/8ths of an inch in diameter.
The number of lamps used in your fixture.
The average number of days a week the lamps operate.
De-lamping is a great way to save money and lower maintenance costs while still producing a similar amount of light.
This is needed to calculate accurate annual savings, which depend upon statewide commercial utility rates.
Ceiling Recessed or Enclosed A fixture where heat from the lamps can accumulate around the lighting when the lamps are enclosed or simply when they are surrounded on the top and sides by the fixture. Most office lighting fits into this category, including the commonly used parabolic troffers.
Open Air Hanging A fixture hanging on or below the ceiling where the lamps are fully exposed to the room environment. A strip fixture is an example of an open air hanging fixture.
Existing lighting often provides an unnecessary amount of light, and reducing light output can save a significant amount of energy. In fact, light output can be reduced by up to 25% without a noticeable change in light levels.
