Improvement of Phase Change Materials (PCM) Used for Solar Process Heat Applications

Abstract

The high intermittency of solar energy is still a challenge yet to be overcome. The use of thermal storage has proven to be a good option, with phase change materials (PCM) as very promising candidates. Nevertheless, PCM compounds have typically poor thermal conductivity, reducing their attractiveness for commercial uses. This paper demonstrates the viability of increasing the PCM effective thermal conductivity to industrial required values (around 4 W/m·K) by using metal wool infiltrated into the resin under vacuum conditions. To achieve this result, the authors used an inert resin, decoupling the specific PCM material selection from the enhancement effect of the metal wools. To ensure proper behavior of the metal wool under standard industrial environments at a broad range of temperatures, a set of analyses were performed at high temperatures and an inert atmosphere, presenting a thorough analysis of the obtained results.

The research leading to these results has received funding from CDTI in the project Innterconecta Thesto (ITC-20111050). The work partially funded by the by the Ministerio de Ciencia, Innovación y Universidades de España (RTI2018-093849-B-C31-MCIU/AEI/FEDER, UE) and by the Ministerio de Ciencia, Innovación y Universidades-Agencia Estatal de Investigación (AEI) (RED2018-102431-T). Dr. Cabeza would like to thank the Catalan Government for the quality accreditation given to her research group GREiA (2017 SGR 1537). GREiA is certified agent TECNIO in the category of technology developers from the Government of Catalonia. This work is partially supported by ICREA under the ICREA Academia programme.