Low-energy LED lighting heat gain distribution in buildings, part 1: Approach and pilot test

Lighting heat gains are a significant contributor to space cooling load in buildings and it is important to determine the lighting heat gain distribution—specifically, the fraction of convective and radiative heat gains, as well as the fraction of conditioned space and plenum space heat gains. Traditional lighting's heat gain distribution has been determined and the data are available on the ASHRAE Handbook. However, there is a lack of relevant data for the light-emitting diode lighting heat gain. As the light-emitting diode technology and application are rapidly growing, the need to identify light-emitting diode lighting heat gain becomes highly demanded. In this project (ASHRAE RP-1681), 14 commercially available light-emitting diode lighting luminaries’ heat gain distributions were determined through systematically designed experiments. The split between the convective heat gain and the radiative heat gain, and the split between the conditioned space heat gain and ceiling plenum heat gain were determined for these luminaries. This article describes the test approach and pilot test results, and a companion article introduces luminaires selection and analyses the formal test results.