Aqueous mid-infrared electrically switchable opaque building envelopes for all-season radiative thermoregulation

30 May 2022, Version 1
This content is a preprint and has not undergone peer review at the time of posting.


Radiative thermoregulation has been considered a promising approach for reducing the heating, ventilation, and air-conditioning (HVAC) energy consumption of buildings and solving the global climate change issues. Electrochromism is a powerful way to dynamically control the heat balance of buildings in response to fluctuating weather conditions, but it has been largely limited to visible and near-infrared wavelength regimes. Here, we develop an aqueous flexible electrochromic system based on graphene ultra-wideband transparent conductive electrode and reversible electrodeposition, which can non-volatilely tune the thermal emissivity between 0.07 (heating) and 0.92 (cooling) with substantial long-term stability and durability. Building energy simulation demonstrates that applying our electrochromic device to building envelopes can save the year-round operational HVAC energy consumption across the U.S., especially in cold climate zone (up to 43.1 MBtu on average among climate zones 5-8). Furthermore, such a dynamic building envelope shows more profound benefits on less insulated buildings, with up to 19.44% of the year-round operational HVAC energy saving for building with only 25% insulation layer, which can serve as a technological solution to retrofit historical buildings or to complement newly constructed buildings with less insulation for lower embodied carbon.


Radiative cooling
Electrochromic device
Smart building envelope


Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.