The roles of thermal insulation and heat storage in the energy performance of the wall materials: a simulation study.

Linshuang Long,Hong Ye

doi:10.1038/srep24181

Abstract

A high-performance envelope is the prerequisite and foundation to a zero energy building. The thermal conductivity and volumetric heat capacity of a wall are two thermophysical properties that strongly influence the energy performance. Although many case studies have been performed, the results failed to give a big picture of the roles of these properties in the energy performance of an active building. In this work, a traversal study on the energy performance of a standard room with all potential wall materials was performed for the first time. It was revealed that both heat storage materials and insulation materials are suitable for external walls. However, the importances of those materials are distinct in different situations: the heat storage plays a primary role when the thermal conductivity of the material is relatively high, but the effect of the thermal insulation is dominant when the conductivity is relatively low. Regarding internal walls, they are less significant to the energy performance than the external ones, and they need exclusively the heat storage materials with a high thermal conductivity. These requirements for materials are consistent under various climate conditions. This study may provide a roadmap for the material scientists interested in developing high-performance wall materials.

Highlights

Cabeza et al, for example, conducted a set of experiments to approve the performance of high internal thermal inertia in Mediterranean climates[13,14], and Stazi et al emphasized the efficiency of external insulations in the same climate[15,16,17,18]
Due to the fact that the thermal insulation and heat storage are inherent and concomitant capacities of the envelopes, some questions remain to be addressed. How do these capacities of a wall affect the energy performance of a building? Does there exist any interaction between these capacities? How do the results diversify for external and internal walls? To answer these questions, one requires an overall concept about the roles of the thermal insulation and heat storage in the energy performance of the envelopes
Despite the varied configurations of buildings, a room with both external and internal walls is a rational and typical physical representation of a building to investigate the overall effect of wall materials

Summary

Introduction

For example, conducted a set of experiments to approve the performance of high internal thermal inertia in Mediterranean climates[13,14], and Stazi et al emphasized the efficiency of external insulations in the same climate[15,16,17,18]. The meaning of the results is inevitably restrained: only a few types of materials or configurations of walls can be compared and evaluated With these limited results, the effects of thermal insulation and heat storage on energy performance can hardly be investigated comprehensively and there is always a lack of a big picture of the overall scene. One requires an overall concept about the roles of the thermal insulation and heat storage in the energy performance of the envelopes Painting such a big picture of wall materials implies that a thorough investigation on buildings is needed. Climate conditions may influence the results of the investigation, so three types of climates (the climate of hot summer and cold winter, that of cold climate and that of hot summer and warm winter) are considered

Objectives

Methods

Results

Conclusion