@article {57807, title = {U.S. energy savings potential from dynamic daylighting control glazings}, journal = {Energy and Buildings}, volume = {66}, year = {2013}, month = {11/2013}, pages = {415-423}, chapter = {415}, abstract = {

Daylighting controls have the potential to reduce the substantial amount of electricity consumed for lighting in commercial buildings. Material science research is now pursuing the development of a dynamic prismatic optical element (dPOE) window coating that can continuously readjust incoming light to maximize the performance and energy savings available from daylighting controls. This study estimates the technical potential for energy savings available from vertical daylighting strategies and explores additional savings that may be available if current dPOE research culminates in a successful market-ready product. Radiance daylight simulations are conducted with a multi-shape prismatic window coating. Simulated lighting energy savings are then applied to perimeter floorspace estimates generated from U.S. commercial building stock data. Results indicate that fully functional dPOE coatings, when paired with conventional vertical daylight strategies, have the potential to reduce energy use associated with U.S. commercial electric lighting demand by as much as 930 TBtu. This reduction in electric lighting demand represents an approximately 85\% increase in the energy savings estimated from implementing conventional vertical daylight strategies alone. Results presented in this study provide insight into energy and cost performance targets for dPOE coatings, which can help accelerate the development process and establish a successful new daylighting technology.

}, keywords = {Clerestories, daylighting, Dynamic prismatic optical elements (dPOE), energy efficiency, Glare, indoor environmental quality, radiance, windows}, doi = {10.1016/j.enbuild.2013.07.013}, author = {Arman Shehabi and Nicholas DeForest and Andrew McNeil and Eric R. Masanet and Jeffery B. Greenblatt and Eleanor S. Lee and Georgeta Masson and Brett A. Helms and Delia J. Milliron} } @booklet {1213, title = {Electro-Responsive Polymer Glazings For Smart Windows With Dynamic Daylighting Control}, year = {2012}, month = {02/2012}, abstract = {

In the context of alarming phenomenon of global warming with harmful consequences such as increased green house gases beyond predictions, the development of advanced energy efficient technologies became of a primary importance. Since the building sector accounts for 39\% of total US primary energy consumption, fenestration can significantly contribute to lowering the energy use for heating, cooling, and lighting. An estimated 9\% reduction in total US building energy use, or 3.47 Q, could be attained by dynamic solar/thermal control and daylighting if these advanced optical technologies were adopted throughout the residential and commercial building sectors. In spite of the great research and engineering efforts in the fast growing area of smart windows, development of glazing devices able to provide efficient, durable, and inexpensive products for dynamic daylight control is in infancy. Like the electrochromic glazings now emerging on the market, microscale, switchable daylight-redirecting glazings have the potential for widespread application if a low-cost, durable coating can be engineered and manufactured with the proper set of attributes.

Here we report on the development of a new technology using smart materials for switchable daylight-redirecting glazings. The proposed system consists in a prismatic optical element (POE) fabricated by micro-imprinting of an elastic redox-active polymer network capable to change its geometry and thereby its optical properties in response to an external stimulus. It is expected that the prismatic optical element reversibly collapses in response to an applied potential, thereby modulating the fraction of light which is redirected. The fabrication of the dynamic prismatic optical element from simulation-driven design to materials synthesis and device integration will be described. Investigation of specto-electrochemical characteristics of the redox-active grating and challenges encountered with respect to electromechanical induced structural changes will be also presented.

}, author = {Georgeta Masson and Rueben Mendlesberg and Irene Fernandez-Cuesta and Stefano Cabrini and Delia J. Milliron and Brett A. Helms and Eleanor S. Lee and Andrew McNeil and Stephen E. Selkowitz} }