We have multiple pathways to design and explore the dynamic facades, while the objectives in these different designs are consistent - utilizing renewable energy sources passively or actively, self-regulatorily or power-actuatively, visibly or imperceptibly; incorporating smart material features; responding to external weather stimuli; and maintaining indoor visual and thermal comfort.
Reversible Photothermal Windows
Achieving the low SHGC in summer seasons in these existing dynamic technologies has to be coupled with low visible transmittance and visual appearance (e.g., color, clarity), which may further negatively affect indoor electrical lighting energy use and daylighting and window view benefits to indoor occupants. Comparatively, the reversible photothermal windows designed in this work exhibit a substantial ability to control solar heat gain coefficient with a range between about 0.2 and 0.6 and a stable visible transmittance of 0.32. The parametric energy simulation method was employed in EnergyPlus to take dynamic SHGC models into account and demonstrated that above 18% energy savings can be obtained in mixed climates by using reversible photothermal windows (as compared to DOE prototype models). In hot and cold climates, the energy savings were minor, ranging from 1.2% to 7%.
Jahid, M. A., Wang, J., Zhang, E., Duan, Q., & Feng, Y. (2022). Energy savings potential of reversible photothermal windows with near infrared-selective plasmonic nanofilms. Energy Conversion and Management, 263, 115705.
Penn State Invention Disclosure 2022-5463
Bimetal-based Thermally Responsive Dynamic Glazed Facade
This is a design to modulate the central layer in the double-pane setting, activated by the thermally responsive bimetallic strips. In different seasons, such strips may facilitate the inward-flowing heat converted from the absorbed solar radiation.
Bio-inspired Building Skin
Inspired by natural models that have honeycombed structures and are able to respond to solar radiation in different ambient temperature situations, this conceptual design used BIM parametric methods to develop a kinetic building skin.
Wang, J., & Li, J. (2010, March). Bio-inspired kinetic envelopes for building energy efficiency based on parametric design of building information modeling. In 2010 Asia-Pacific Power and Energy Engineering Conference (pp. 1-4). IEEE.