Dynamic simulation of blind control strategies for visual comfort and energy balance analysis

The presented study describes a method for evaluating control strategies for shading devices. The method is based on dynamic lighting simulations with RADIANCE and DAYSIM and explores energy, daylight supply and visual comfort parameters at the same time. In order to include the glare aspect more effectively in dynamic building simulations, a simplified glare measure “Daylight Glare Probability simplified (DGPs)” is presented and validated for situations when the sun does not hit the eye directly. For the evaluation of the solar thermal loads, a simplified method based on RADIANCE and DAYSIM is described to calculate dynamically the energy flux through facades for external mounted shading devices. The evaluation of different simulated shading control strategies show that the commonly used manual control strategies hardly activate the shading in summer. Therefore, the solar loads in summer for these strategies are very high and at the same time glare and low contrasts at the visual display unit (VDU) occur. The automated cut-off strategy seems to be a good compromise between energy and comfort aspects, especially in summer.