The present invention relates to a building. The building includes a distributed power supply and a lighting system for being powered by the distributed power supply. The system includes distributed lights for being coupled to the distributed power supply. Covers are provided for covering respective lights. Photoluminescence is borne by each cover. Advantageously, the light charges the photoluminescence borne by the cover. In turn, the cover passively discharges and provides passive illumination in the dark by virtue of the photoluminescence. The building lighting system provides illuminationfor after-hours personnel in the building after the light is turned off, or in the event of a power disruption when a backup power generator is not present.