Si 3 N 4 nanofelts/paraffin composites as novel thermal energy storage architecture
- PDF / 5,559,570 Bytes
- 14 Pages / 595.276 x 790.866 pts Page_size
- 77 Downloads / 180 Views
Si3N4 nanofelts/paraffin composites as novel thermal energy storage architecture Francesco Valentini1,* , Andrea Dorigato1, Alessandro Pegoretti1, Michele Tomasi1, Gian D. Soraru`1, and Mattia Biesuz1 1
Department of Industrial Engineering and INSTM Research Unit, University of Trento, Via Sommarive 9, 38123 Trento, Italy
Received: 21 April 2020
ABSTRACT
Accepted: 31 August 2020
The environmental problems associated with global warming are urging the development of novel systems to manage and reduce the energy consumption. An attractive route to improve the energy efficiency of civil buildings is to store the thermal energy thanks, during heating, to the phase transition of a phasechange material (as paraffin) from the solid to the liquid state and vice versa. The stored energy can be then released under cooling. Herein, we developed a novel material (nanofelt) constituted by Si3N4 nanobelts able to absorb huge amounts of liquid paraffin in the molten state and to act as an efficient shape stabilizer. The nanofelt manufacturing technology is very simple and easy to be scaled-up. The effect of the Si3N4 nanofelts density and microstructure on the paraffin sorption and leakage and on the thermal properties of the resulting composite structures is investigated. It is shown that the produced Si3N4/paraffin composites are able to retain enormous fractions of paraffin (up to 70 wt%) after 44 day of desorption test on absorbent paper towel. The thermal energy storage efficiency measured through calorimetric tests is as high as 77.4% in heating and 80.1% in cooling.
Ó
The Author(s) 2020
Introduction In the last decades, the accumulation of greenhouse gases related to human activities has caused chemical changes in the atmosphere, becoming the main reason for global warming [1–3]. In this context, the development of energy storage systems is essential for managing the energy demand and for reducing
Handling Editor: N. Ravishankar.
Address correspondence to E-mail: [email protected]
https://doi.org/10.1007/s10853-020-05247-5
the human carbon footprint. Such systems work as accumulators of an available energy form (thermal, electric, chemical, etc.) which can be used at a later time [3–7]. Thermal energy storage (TES) allows the accumulation of thermal energy that can be used for thermal management applications, such as to balance the energy demand of civil buildings, thus reducing the energy absorption peaks [7–10]. Among the different TES architectures, latent heat thermal energy
J Mater Sci
storage systems are of great interest as they allow to store huge amounts of thermal energy (at a constant temperature) thanks to the phase transition of a material from a physical state to another (for example from liquid to solid and vice versa) [10–13]. For this reason, they are mostly based on the so-called phasechange materials (PCM). Paraffins are the most used organic-PCM due to the low cost, the high heat of fusion/solidification, the broad range of melting temperatures and the chemical stability [13, 1
Data Loading...
