Well-designed electrochromic (EC) glazing control can improve the energy performance of buildings and visual comfort of occupants in highly glazed buildings. This paper designed and demonstrated a compact integrated EC glazing automation system to control tint states of a split-pane EC window according to variations of sky conditions. The control is based on monitoring the luminance distribution of the sky and real-time lighting computation for a building interior, using an embedded photometric device (EPD). It optimizes tint states of EC glazing to offer sufficient daylight provision and temper discomfort glare for occupants, which potentially mitigates excessive solar heat gain. ’In-situ’ experiments were conducted in a full-scale testbed to demonstrate the daylighting performance under various sky conditions. Experimental results showed 83% of the working time for work-plane illuminance (WPI) and 95% of the time for daylight glare probability (DGP) were constrained in comfort range (WPI∈[500, 2000] lux, DGP ≤ 0.35) by the automated EC glazing (controlled by EPD) under clear skies; 68% of the time for WPI and 94% of the time for DGP in confined range under clear skies with thin clouds; 62% of the time for WPI and 85% of the time for DGP in confined range under partly cloudy skies.
BT - Building and Environment C2 - LBNL-2001231 DA - 08/2019 DO - 10.1016/j.buildenv.2019.106229 LA - eng N2 -Well-designed electrochromic (EC) glazing control can improve the energy performance of buildings and visual comfort of occupants in highly glazed buildings. This paper designed and demonstrated a compact integrated EC glazing automation system to control tint states of a split-pane EC window according to variations of sky conditions. The control is based on monitoring the luminance distribution of the sky and real-time lighting computation for a building interior, using an embedded photometric device (EPD). It optimizes tint states of EC glazing to offer sufficient daylight provision and temper discomfort glare for occupants, which potentially mitigates excessive solar heat gain. ’In-situ’ experiments were conducted in a full-scale testbed to demonstrate the daylighting performance under various sky conditions. Experimental results showed 83% of the working time for work-plane illuminance (WPI) and 95% of the time for daylight glare probability (DGP) were constrained in comfort range (WPI∈[500, 2000] lux, DGP ≤ 0.35) by the automated EC glazing (controlled by EPD) under clear skies; 68% of the time for WPI and 94% of the time for DGP in confined range under clear skies with thin clouds; 62% of the time for WPI and 85% of the time for DGP in confined range under partly cloudy skies.
PY - 2019 EP - 106229 ST - Building and Environment T2 - Building and Environment TI - Split-pane electrochromic window control based on an embedded photometric device with real-time daylighting computing UR - https://linkinghub.elsevier.com/retrieve/pii/S0360132319304391 VL - 161 SN - 03601323 ER -