Increasing Light Output and Efficacy of Recessed Troffers with Spot Coolers

A potentially energy saving heat sink device for use in common fluorescent luminaires is presented. This heat sink, or Spot Cooler, increases luminaire efficiency by eliminating losses of light output and system efficacy that normally occur when lamps are heated beyond optimal temperatures in the thermally constrictive lamp compartment typical of most recessed luminaires. Unlike cooling devices suggested in the past, the Spot Cooler presented is inexpensive and completely passive, yet maintains an optimum performance level by recovering light losses that can vary from 10 to 25%. While the prototypes presented were designed for and tested with F40T12 type lamps utilized in standard recessed troffers, the design could be modified for any cylindrical fluorescent lamp type utilized in many standard fixture geometries.