Influences of lighting control and natural ventilation on energy use and overheating for a day-lit industrial building

Overheating in buildings not only causes discomfort to the occupiers but – if it occurs regularly or over a sustained period – also leads to pressure for the installation of mechanical cooling. In addition to the initial cost and ongoing maintenance requirements of such systems there will be an increase in the overall energy use of the building. This paper investigates the thermal performance of an industrial building (retail shed) with rooflights by means of dynamic computer modelling. The effects of lighting control and natural ventilation on overall energy consumption and overheating were performed by using this model. The modelling results clarify that these methods substantially reduce overheating hours as internal heat is dissipated through the openings and lighting heat gains are cut. In addition, overall CO2 emissions can be cut by over 25% by using daylight sensing controls. All in all, natural ventilation at ridges of the roof together with lighting control reduces overheating to commonly acceptable levels without recourse to mechanical cooling.