Circadian Daylight Performance of the Electrochromic Glazing
A workflow for analysis of the EC Window non-visual daylight performance
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Overview
Abstract
Electrochromic windows introduced to building market as a smart glare control solution to provide visual comfort for building occupant. EC glazing can improve human health and comfort, by changing its visual and thermal properties to block glare, heat and balance daylight. The majority of previous studies on the daylight performance of the Electrochromic windows were focused on evaluation of the visual effect of light. However, recent findings on the nonvisual effects of light on human health, confirm the necessity of assessing the circadian light performance of the EC glazing.
This study proposes a framework for evaluating the nonvisual effects of light through the development of an algorithm for measurement of circadian light in the spaces with EC windows. This algorithm is based on modeling eye-level light exposures to analyze the availability of circadian effective daylight stimulus. Since EC glazing in multi-zone configuration can dynamically change its tint pattern, this study investigates the effect of each tint state on filtering the photopic and melanopic light.
EC glazing can be used in a single or multi-zone configuration. This workflow can evaluate the impact of zoning on daylight performance for addressing human non-visual needs. The applicability of the Workflow is demonstrated using an example model: an office space with south-facing window-wall with Electrochromic glazing. The result of the analysis is presented in the format of: hourly interior map of visual and non-visual effective area.
Authors
Ahoo Malekafzali. PhD.
Sr. Technical Solutions Consultant
Sage Glass
ahoo.malekafzaliardakan@sageglass.com
Keywords
Introduction
With the recent research findings that prove the impact of light on human health and wellbeing, the importance of well daylight design in the indoor environment is more clear to
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Background
The human eye has a dual role in detecting light for a range of behavioral and physiological responses separate and apart from sight. The discovery of non-rod, non-cone photoreceptor (ipRGCs)
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Method
Electrochromic glazing dynamically changes its tint state to block glare, balance daylight and transmitted heat. To assess the impact of EC on circadian light a simulation workflow was developed including
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Data
Simulation results for all the daylight hours of March 21st are reported for three test case of Single zone EC, Multi-zone EC and, clear low E glazing systems. For each
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Explanation
In this study a new modeling workflow has been developed for evaluation of the circadian light performance of EC window. Properties of light that impact non-visual photoreception are Wavelength, Intensity
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Conclusion and Future Work
Electrochromic glazing in multi-zone configuration has the best visual and non-visual performance among all tested options. Even though the simulated control strategy was designed to optimize visual comfort, its impact
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Rights and Permissions
Andersen, Marilyne, John Mardaljevic, and Steven W. Lockley. "A framework for predicting the non-visual effects of daylight–Part I: photobiology-based model." Lighting research & technology 44, no. 1 (2012): 37-53.
Andersen, Marilyne, John Mardaljevic, and Steven W. Lockley. "A framework for predicting the non-visual effects of daylight–Part I: photobiology-based model." Lighting research & technology 44, no. 1 (2012): 37-53.
Mardaljevic, John, Marilyne Andersen, Nicolas Roy, and Jens Christoffersen. "A framework for predicting the non-visual effects of daylight–Part II: The simulation model." Lighting Research & Technology 46, no. 4 (2014): 388-406.
Konis, Kyle. "A novel circadian daylight metric for building design and evaluation." Building and Environment 113 (2017): 22-38.
Gronfier, Claude. “Non-visual photoreception: current knowledge”. Institut Cellule Souche et Cerveau, Département de Chronobiologie, Bron, Franc (2014)
Thapan, Kavita, Josephine Arendt, and Debra J. Skene. "An action spectrum for melatonin suppression: evidence for a novel non‐rod, non‐cone photoreceptor system in humans." The Journal of physiology 535, no. 1 (2001): 261-267.
Brainard, George C., John P. Hanifin, Jeffrey M. Greeson, Brenda Byrne, Gena Glickman, Edward Gerner, and Mark D. Rollag. "Action spectrum for melatonin regulation in humans: evidence for a novel circadian photoreceptor." Journal of Neuroscience 21, no. 16 (2001): 6405-6412.
Figueiro, M. G., G. C. Brainard, S. W. Lockley, V. L. Revell, and R. White. "Light and human health: An overview of the impact of optical Radiation on visual, circadian, neuroendocrine, and neurobehavioral responses." Illuminating Engineering Society Technical memorandum, IES TM-18-08 (2008).
Roudsari, Mostapha Sadeghipour, Michelle Pak, and Adrian Smith. "Ladybug: a parametric environmental plugin for grasshopper to help designers create an environmentally-conscious design." In Proceedings of the 13th international IBPSA conference held in Lyon, France Aug. 2013.
Rhinoceros 3-D Modeling Program. http://www.en.na.mcneel.com/contact.htm.
Solemma, DIVA for Rhino. https://www.solemma.com/Alfa.html.
Jakubiec, J. Alstan, and Christoph F. Reinhart. "DIVA 2.0: Integrating daylight and thermal simulations using Rhinoceros 3D, Daysim and EnergyPlus." In Proceedings of building simulation, vol. 20, no. 11, pp. 2202-2209. 2011.
Malekafzali Ardakan, Ahoo, “A Workflow for Assessing Circadian Daylight Performance of the Electrochromic Glazing”, 2018 Building Performance Analysis Conference and SimBuild, September 26-28, 2018, Chicago, IL, USA.