LEVEL 3 BUILDING SERVICES TRAINING LIGHTING CONTROLS Appropriate lighting controls can yield substantial improvements in lighting energy efficiency These improvements arise principally from the utilisation of available daylight to reduce electric lighting use and from switching off electric lighting when a space is unoccupied. In addition they can increase user satisfaction by allowing occupants to have more control over their working environment through the use of localised switches. To be energy efficient, lamps must be switched on to provide light only when it is required, and switched off when it is not. Both automatic and manual switching of lamps will adversely affect lamps by shortening their service life. This effect is minimal; the energy cost saved by switching lamps off recovers the cost of shortening lamp life within a few minutes. Provided that lamps are to be left off for periods of more than two or three minutes it is always cost effective to switch off.