Typical harvesting applications are in large facilities with window walls and in commercial and institutional buildings using skylights. For example, a facility manager may recognize that the conference room is used every day from 10 a.m. to 11 a.m. The lighting system could be programmed to dim the lights for the hours that the room is not occupied. Load shedding is used to determine appropriate light levels while minimizing energy consumption and lowering operating costs during peak hours. Utility companies often charge premiums for energy usage during these times.
Facilities operating with set schedules can reduce energy consumption with load schedules.
Maintaining proper light levels and dimming the lighting system when appropriate also support facility energy management. Maintenance is easy on these systems. Most fluorescent electronic dimming ballasts now include circuitry that monitors lamp cathode voltage, which protects lamp life and safeguards the ballast against improper installation. The ballasts also ignite lamps at any pre-set level, so the ballast no longer has to be on 100 percent to ignite the lamp. Dimming models maintain light levels over the life of a system.