The initial photometric performances of street lighting luminaires are compared using different types of sources, and associating the luminous efficiency of the lamp and the useful efficiency of the optics of the luminaire. The analysis shows that the high pressure sodium (HPS) or low pressure sodium (LPS) discharge lamp associated with capable optics can provide useful efficiencies three times higher than luminaires using the mercury vapour (HPMV) and the fluorescent (FL) lamp. The photometric performances should be accompanied by good leak tightness performances of the luminaire to ensure the best possible retention over time of the initial photometric performances. Thanks to these performances, a high maintenance factor can be adopted. A new criterion is proposed quantifying the maintained performances of a street lighting luminaire. (A)
Samenvatting