Active shading devices for eco-efficient buildings

• More energy is spent conditioning our indoor climate (e.g., heating, cooling, lighting) than on any other human activity.
• No building facade technology is capable of dynamic optical reconfigurability for comprehensive climate control because of the constraints imposed by solid-state materials/systems.
• This platform technology is capable of dynamically and independently controlling the amount (intensity), spectrum (wavelength band), and direction (scattering distribution) of transmitted solar radiation, enabling significant improvements in building energy efficiency.

TECHNOLOGY

• Taking advantage of confined fluidic materials, we have developed the first optically-general platform for independently controlling the intensity, spectrum, and dispersion of transmitted solar radiation in buildings.
• Our simple, window-mountable system is comprised of overlapping millimeter-scale channeled structures, milled from a transparent plastic/glass sheet, wherein different liquids can be digitally and reversibly introduced, via pump, in different combinations to achieve a variety of optical/thermal configurations.
• We have developed prototypes up to a size of 0.5x0.5 m2, and tested/validated a range of combinatorial digital optical/thermal responses achievable therein (TRL 4/5).
• Additional embodiments of the device enable more advanced fluid shape-programmability, where the shape/size of several liquid/gas macro-droplets (up to 30 cm in diameter) within an array can be individually controlled for achieving a differential spatial gradient of an optical/thermal response.

BENEFITS

• Traditional solid-state building materials cannot independently tune the intensity, spectrum, and dispersion of transmitted sunlight within a room, resulting in large heating/cooling/lighting energy inefficiencies. Our fluidic system is the first that can individually and dynamically tune these three parameters, enabling configurable optimization of the amount, wavelength, and position of transmitted sunlight over time.
• The level of general optical and thermal tunability that our fluidic system enables annual modelled energy reductions of more than 43% over state-of-the-art existing electrochromic technologies.
• Compared to existing opto-electronic systems that rely on complex electrochemistry (and often toxic components that enable it), our simple fluidic design leverages a palette of replenishable/clean water-based materials, offering green material processing/fabrication.

APPLICATIONS

• Our fluidic multilayer can be applied along, or can be manufactured into, a building window. Its flexible design/application strategy can ease and broaden implementation strategies and use-cases, geared toward any existing or new window system in development.
• The market for energy-efficient building screens/systems is rapidly growing, as governments demand building energy-neutrality by 2030. Optically-reconfigurable window systems will become standard, while existing window systems (of large prevalence in all-glass towers) will require retrofitting.

STATUS

• PCT filed Winter 202
• Work is focusing on scale-up, implementation optimization, and advancing TRL. Near-market prototypes ready for testing within 24 months.
• Seeking strategic partnerships with engineering/manufacturing companies (e.g., window manufacturing), development/construction companies/firms (e.g., building planning/construction), and architecture firms (e.g., building design) to provide venues for testing and facilities for fabrication/design/development.