Analysis of Heating and Cooling Loads of Electrochromic Glazing in High-Rise Residential Buildings in South Korea

Myunghwan Oh,Sangkun Hwang,Sungho Tae

doi:10.3390/su10041121

Abstract

This study compares the impact of the recently developed electrochromic glazing technology on load reduction by comparing it with the double-glazing and shading devices that are sold commercially for high-rise residential buildings in Korea. These buildings are similar to large office buildings in terms of their high window-to-wall ratio. The energy consumption of such buildings was simulated using an analytical model of a high-rise residential building. The patterns between the heating and cooling loads were found to be similar to that of office buildings, in that the cooling load was considerably higher than the heating load. This study hypothesizes that the load reduction performance of electrochromic glazing with variable solar control and high solar radiation rejection is superior to that of existing double-glazing products and shading devices. This hypothesis was tested by analyzing the cooling and heating loads of buildings with different types of double glazings. Bleached electrochromic glazing exhibited lower transmittance than colored glass double glazing, low-e double glazing, and double glazing with a shading device, and is thus not effective in reducing heating load. Colored electrochromic glazing provided higher solar radiation rejection than colored glass double glazing and low-e double glazing, and thus is effective in reducing cooling load.

Highlights

The objective of this study is to analyze the optical properties of test products for the commercialization of large-area electrochromic glazing for the first time in Korea, to the best of the authors’ knowledge, and determine whether the optical properties are effective at reducing the energy consumed by buildings
We aim to test the second hypothesis, that electrochromic glazing with variable solar control and high solar radiation rejection is more effective at reducing the load on buildings compared with existing double-glazing and shading devices
For the evaluation of hourly heating and cooling loads, we analyzed the hourly changes in heating load according to the type of double glazing under the conditions obtained on the design day using meteorological data for Seoul

Summary

Introduction

Windows and doors are the only glazing systems that can capture solar energy. They can serve as a medium that reduces building load and improves the indoor environment through appropriate inflow and the rejection of solar radiation [1]. Windows and doors require separate shading devices for solar control, such as roll shades or blinds. Smart glass, which does not need any separate shading device to control the optical properties of glass and, solar radiation, has recently been actively researched in the literature. This study analyzes the optical properties of electrochromic glazing and its effect on HVAC (Heating, ventilation, air conditioning) load reduction in buildings [4,5]

Objectives

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Results