Short-term storage systems of thermal energy for buildings: a review

Thermal energy storage in buildings is essential to reduce energy consumption, to switch electrical consumption from on-peak period to off-peak period and to develop the use of intermittent renewable energy sources. Several systems designed to store thermal energy on a short-term scale (maximum a few days of storage) are presented in previous publications. However, there are no available comparisons of these systems and their conditions of use. This paper details these different designs for short-term scale thermal energy storage, regarding (i) their passive or active nature, (ii) their usage conditions and (iii) their performances. In the first section, the thermal properties of materials are listed. In particular, advantages and problems associated with phase change materials are presented. Subsequently, thermal storage systems are presented in two parts, on the one hand, passive systems and on the other hand active systems, according to the fluid used. For each system, the advantages of substituting sensible storage with latent storage are highlighted. Furthermore, an original and comparative analysis of published studies attempts to define some criteria and requirements for efficient use of latent storage. This review demonstrates that an exhaustive comparison of the systems encounters difficulties, due to the differences between the studies with respect to experimental measurements and weather data and the lack of similar comparison criteria, such as decrement factor, efficiency and cost.