02354nas a2200229   4500008003900000245013200039210006900171260001200240300001000252490000800262520159100270653003201861653001801893653001801911653001201929100002101941700001801962700002101980700001802001700002902019856007602048       2013                          d00aAn empirical study of a full-scale polymer thermochromic window and its implications on material science development objectives0 aempirical study of a fullscale polymer thermochromic window and   c09/2013  a14-260 v1163 a<p>Large-area polymer thermochromic (TC) laminated windows were evaluated in a full-scale testbed office. The TC interlayer film exhibited thermochromism through a ligand exchange process, producing a change in solar absorption primarily in the visible range while maintaining transparent, undistorted views through the material. The film had a broad switching temperature range and when combined to make an insulating window unit had center-of-glass properties of Tsol=0.12-0.03, Tvis=0.28-0.03 for a glass temperature range of 24-75°C. Field test measurements enabled characterization of switching as a function of incident solar irradiance and outdoor air temperature, illustrating how radiation influences glass temperature and thus effectively lowers the critical switching temperature of TC devices. This was further supported by EnergyPlus building energy simulations. Both empirical and simulation data were used to illustrate how the ideal critical switching temperature or temperature range for TC devices should be based on zone heat balance, not ambient air temperature. Annual energy use data are given to illustrate the energy savings potential of this type of thermochromic. Based on observations in the field,a broad switching temperature range was found to be useful in ensuring a uniform appearance when incident irradiance is non-uniform across the facade. As indicated in prior research, a high visible transmittance in both the switched and unswitched state is also desirable to enable reduction of lighting energy use and enhance indoor environmental quality.</p>10abuildings energy efficiency10aSolar control10aThermochromic10awindows1 aLee, Eleanor, S.1 aPang, Xiufeng1 aHoffmann, Sabine1 aGoudey, Howdy1 aThanachareonkit, Anothai  uhttps://facades.lbl.gov/publications/empirical-study-full-scale-polymer