Peter Ngai, Vice President of Peerless Lighting, based in Berkeley, California, evaluated all three lamp types against a set of objective criteria, including:
– Power
– Efficacy (lumens/watt)
– Optimum operating temperature
– Warm-up time
In his presentation he stated:
– When a T8 lamp is run on a high-frequency electronic ballast, it needs only 28 watts to produce 2,900 lumens. “So the efficacy of the T8 is the same as that of the T5 and 10% higher than that of the T5HO”.
– For two luminaires of the same size, the one with a T5 lamp will have better optical efficiency than the one with a T8.
– In a single luminaire, fitting one T5HO will give better optical results than fitting two lamps (per lamp), because in a two-lamp system the optics have to be adapted considerably, which reduces the efficiency of the luminaire.
– Generally speaking, for indirect lighting applications the T5HO is the most desirable light source, thanks to its small size combined with its high lumen output, which allows luminaire designers to create better light distributions with minimal loss of efficiency.
