Efficient lighting strategies for office rooms in tropical climates

The “Green Lighting” research project, initiated at the Solar Energy and Building Physics Laboratory (LESO-PB) of the Swiss Federal Institute of Technology in Lausanne (EPFL), is aiming at an energy efficient integration of advanced daylighting and electric lighting systems. This communication presents the latest developments within this project and discusses possible consequences for offices in tropical climates. A computer model of a Singapore office room equipped with an Anidolic Integrated Ceiling, for which daylight autonomies have recently been calculated at National University of Singapore, has been developed using the RELUX Vision lighting software. An appropriate complementary electric lighting system for this office room is suggested and its performance in terms of visual comfort is discussed. It is shown that this electric lighting system would lead to a lighting power density lower than 5 W/m² and would consume less than 1 kWh of electricity per day.