Abstract:
Thermal energy storage (TES) has been one of the main
research topics during the last decades. The increase of energy
costs and the growth of awareness of environmental concerns
have promoted the development of new technologies and new
materials for energy storage. Developing new materials with
high storage density, thermal stability and low cost would
reduce energy cost and improve the energy efficiency in wellknown
and established processes by recovering and storing
heat. Moreover, it would solve the renewable intermittence.
The aim of this study is to formulate a NaNO3/MgO/Cg
composite for intermediate temperature TES applications.
Several compositions with different amounts of NaNO3 as
PCM, MgO as the ceramic matrix and graphite as thermal
conductivity enhancer have been formulated. The main
properties related to thermal energy storage applications have
been characterized: melting point, latent heat, specific heat,
thermal conductivity and thermal expansion coefficient. After
being cycled the microstructure of the composite was
characterized as well as their thermal properties in order to
study the stability when they are charged and discharged at
working conditions. The results show that the melting point of
the PCM remains around the pure molten salt, the latent heat
increases with the PCM content, as expected, as well as the
energy density of the composite. Combining the effect of Cg
addition and the insertion of the PCM in a ceramic matrix a
novel TES material with enhanced thermal conductivity has
been developed.
Description:
Papers presented to the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Costa de Sol, Spain on 11-13 July 2016.
