Thermal Energy Storage Materials in Buildings

Approximately 50% of global energy consumption is in the form of heat, of which about half is attributed to the building sector. The electrification of residential and commercial buildings using renewable sources requires energy storage technologies to balance intermittent supply with demand. This chapter discusses the role of thermal energy storage (TES) near ambient temperatures in reducing operational carbon emissions from buildings via load shifting and peak load shaving when integrated with HVAC. Three major classes of thermal storage are described: sensible heat, latent heat (phase change), and thermochemical heat. An overview of material properties, component design, HVAC system integration, and cost analysis (where available) is provided, which highlights ongoing research efforts from a global perspective. While water and ice-based storage are most mature from a commercial standpoint, many practical challenges remain. To this end, research efforts focused on fundamental research and development of phase change and thermochemical materials, as well as cost-effective and efficient integration of thermal storage with HVAC systems, can unlock the full potential of TES for decarbonizing the buildings sector.