Daylighting and thermal performance of automated split-controlled blinds

Manual blinds are not often adjusted properly. Consequently, electrical lighting as well as heating and cooling loads are increased. The conventional automated control maintains the same blind tilt angle at a particular point in time. An innovative automated split blind system was developed to improve the daylighting and thermal performance of blinds as an integral part of the other building systems. The research objectives were to develop a simplified control method for the split blinds, and to analyze daylighting performance and energy savings due to the application of the split blinds and the control method. A case study that focused on three automated blind systems (conventional (optimum), split (predicted) and split (optimum)) was conducted to analyze the effectiveness of the control methods and the daylighting and thermal performance of the split blinds. Computer simulations were performed using the software EnergyPlus™ to calculate the illuminance levels and glare in a building, and energy consumption as a result of the application of these three blind systems. The simulation results showed that the split blinds (both predicted and optimum) had a better daylighting performance in the back of the room and caused lower energy consumption, especially in winter times when compared to the conventional blinds. An integration of an effective electrical lighting control system is required to fully utilize the advantages of split blinds in summer.

► We developed and evaluated a new practical control method for split blinds.
► Split blind control methods increase daylight levels and reduce energy consumption.
► Split blinds provide more daylight than conventional blinds in the room depth during wintertime.
► Split blinds cause lower energy consumption for electrical lighting than conventional blinds.
► Split blinds have a better daylighting and thermal performance in winter-dominated areas.