What is the economic benefit of T5 systems?
The answer to this question may differ from one case to another. As discussed in Does a T5 lamp give as much light as a T8 lamp, T5 lamp-ballast systems are not significantly more efficacious than T8 lamp-ballast systems. Although the smaller lamp size and use of fewer lamps per luminaire (because of the higher light output of T5 lamps) can improve the optical efficiency of T5 luminaires, the temperature
issue discussed in Do T5 luminaires perform better than T8 luminaires complicates the photometry of T5 systems. The superiority in optical efficiency of T5 luminaires over T8 luminaires may reduce electric energy use slightly. With respect to initial costs, T5 luminaires may have significant benefits if the higher output of T5 lamps leads to a large reduction in the number of lamps and luminaires per project, especially for large commercial projects (see the CASE