Office lighting retrofit using dimmable electronic ballasts and occupancy controls

To demonstrate the potential for improved performance from office lighting through retrofit of electronic ballasts and digital controls several floors of a high-rise Government building built in the 1980s were selected for a demonstration project. The retrofit project, funded by the US-AEP, was carried out in two stages. The first stage was a straightforward retrofit on two half-floors of non-dimmable electronic ballasts, replacement lamps, but retaining the basic luminaire. The second stage was a retrofit on one whole floor using dimmable 'digital' electronic ballasts linked to an integrated sensor incorporating constant illuminance, occupancy detection and hand-held remote control. The luminaire itself was modified and T8 lamps installed. Meters were installed for the continuous monitoring of electricity use in the retrofitted floor and a 'control' floor. The meters measured the energy consumption, power factor, and harmonics content for the lighting circuits. Measurements of the lighting level were made before and after the retrofits. Occupants' opinion surveys were also carried out using questionnaires before and after the retrofit. This paper discusses the measured energy savings, a comparison of power quality and occupants' opinions of the retrofits.