Investigation of Thermochromic and Cool Surface Coating in Reducing Energy Use from Buildings Considering Current and Future Weather Data

Thermochromic (TC) coatings can change their color, reflectivity, and absorptivity based on temperature. In buildings, they help reflect solar radiation during summer and absorb it in winter, reducing heating demand. Research has shown that TC materials can lower winter heating penalties by dynamically adjusting their solar reflectance. Most current studies rely on typical meteorological year (TMY) weather data, which may not account for future climate changes. As global temperatures rise, heating needs are expected to decrease, while cooling demands will increase. This study uses EnergyPlus simulations to assess the performance of TC and cool surface coatings under both current TMY and projected future weather conditions. It aims to offer insights into the effectiveness of these technologies in different climates and building types. A prototype building model from the U.S. Department of Energy is used, covering both residential and commercial types, in two climate zones: cold humid (6A) and hot dry (2B). Results show that in the hot city, total energy use for cooling and heating increases by 2-16% under future conditions, while in the cold city, it decreases by 20–30%. In commercial buildings, over 90% of total energy for space conditioning in the hot city is used for cooling, whereas in the cold city, over 70% is for heating-except in large offices. Cool surfaces reduce total energy use in the hot city by up to 2.9%, compared to 0.3% for TC coatings. The study highlights the importance of considering future climate scenarios when evaluating adaptive building envelope technologies.