A new LED luminaire system architecture for energy saving

This study evaluated a new light-emitting diode (LED) luminaire system architecture in low profile to harvest the otherwise wasted heat generated by LEDs for integrative lighting and heating in buildings. A portable calorimeter was built, commissioned and calibrated in a well-controlled Cold Room for measuring the ‘conditioned space/ceiling plenum split’ of the heat generated by LED luminaires. Two prototypes LED luminaires that adopted the new system architecture were tested together with two off-the-shelf commercial LED luminaires with conventional system architectures for comparison. Each luminaire was either ceiling recessed or ceiling surface mounted in the calorimeter, both were evaluated in summer and winter conditions. The measured ‘conditioned space/ceiling plenum split’ was then used as an input in Energy Plus, with two assumptions, for estimation of the annual heating, reheating and cooling energy consumptions of each luminaire once implemented in a primary school classroom. The simulation results revealed that the new luminaire system architecture especially when surface mounted can outperform the conventional architectures to slightly reduce the building annual heating and reheating energy consumptions without significantly increasing cooling energy consumption. This study validated the potential of integrative lighting and heating. Further studies are necessary to overcome several limitations.