Lighting pollution, the benefit/cost approach

Abstract

One of the urban lighting objectives is to extend people’s activities during night. In this case lighting is linked with functions as visibility, safety, security and visual appearance of the surroundings. Considering these aspects, a current design criteria evaluates the benefit/ cost relationship during the life cycle (LC) of the lighting installations. The benefit in this case is associated to quality parameters of the lighting service like lighting level, failure rate, actual switching schedule and appearance. Other factors related to environmental impact like unnecessary energy consumption, lamp disposal and lighting pollution are interrelated and should also be considerate in the design process. Lighting is essential, but it is a source of pollution. Lighting pollution to a certain extent keeps relationship with the energy waste and could be evaluated by means of the benefit/cost relationship. The present paper describes the use of the benefit/cost LC analysis of conventional installations for urban lighting, considering the upper luminous flux emitted directly from lighting installations and emitted by urban surface reflection. In these cases the benefits/ cost relationship is analysed and the results obtained discussed.