United States energy and CO2 savings potential from deployment of near-infrared electrochromic window glazings

Abstract This paper presents a simulation study of the energy and CO2 benefits of a transparent, near-infrared switching electrochromic (NEC) glazing for building applications. NEC glazings are an emerging dynamic window technology that can modulate the transmission of NIR heat without affecting transmission of visible light. In this study, a hypothetical NEC glazing is simulated on clear and tinted glass in six building type models in 16 U.S. climate regions using Energy Plus 7.1. The total annual energy consumption for lighting, heating, cooling, and ventilation for the NEC glazings are compared with high performance static windows and conventional tungsten-oxide EC glazings. Using regional CO2 intensities and building stock totals, the results from individual building model simulations are scaled up to national totals. The U.S. national savings from NEC deployment is found to be 167 TWh/yr (600 PJ/yr) compared to the existing building stock, but only 8 TWh/yr (29 PJ/yr) or 1.56 million tonnes of CO2 per year when compared to high performance static glazings with lighting controls installed. NEC performance varied significantly by building type and location. This analysis reveals that 50% of the total energy savings can be realized by deploying NEC glazings in only 18% of the total window stock, and 75% of the savings in only 39% of the stock. The best performing locations include medium offices and midrise residential buildings in northern climates, where energy savings per unit window area range from 50 to 200 kWh/m2-yr.

[1]  Robert Clear,et al.  Advancement of Electrochromic Windows , 2006 .

[2]  Sabine Hoffmann,et al.  Examination of the technical potential of near-infrared switching thermochromic windows for commercial building applications , 2014 .

[3]  Stephen Selkowitz,et al.  The energy-savings potential of electrochromic windows in the US commercial buildings sector , 2004 .

[4]  Evan L. Runnerstrom,et al.  Dynamically modulating the surface plasmon resonance of doped semiconductor nanocrystals. , 2011, Nano letters.

[5]  Eleanor S. Lee,et al.  Lighting energy savings potential of split-pane electrochromic windows controlled for daylighting with visual comfort , 2013 .

[6]  Delia J. Milliron,et al.  Near‐Infrared Spectrally Selective Plasmonic Electrochromic Thin Films , 2013 .

[7]  Hong Mo Yang,et al.  Electrochromic dynamic windows for office buildings , 2012 .

[8]  Aslihan Tavil,et al.  Energy and visual comfort performance of electrochromic windows with overhangs , 2007 .

[9]  Claes G. Granqvist,et al.  Handbook of inorganic electrochromic materials , 1995 .

[10]  Dariush Arasteh,et al.  Future advanced windows for zero-energy homes , 2002 .

[11]  Adélio Rodrigues Gaspar,et al.  Evaluation of electrochromic windows impact in the energy performance of buildings in Mediterranean climates , 2014 .

[12]  Spiros Papaefthimiou,et al.  Energy performance assessment of an electrochromic window , 2006 .

[13]  Daniel E. Fisher,et al.  EnergyPlus: creating a new-generation building energy simulation program , 2001 .

[14]  David B. Belzer.  An Exploratory Energy Analysis of Electrochromic Windows in Small and Medium Office Buildings - Simulated Results Using EnergyPlus , 2010 .

[15]  Eric Masanet,et al.  Regional performance targets for transparent near-infrared switching electrochromic window glazings , 2013 .

[16]  D. Arasteh,et al.  Thermal and optical analysis of switchable window glazings , 1991 .