Storage Efficiency of Cold-Crystallizing Long-Term Heat Storage Material

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

3 Downloads (Pure)

Abstract

Efficient and compact long-term heat storage material would enable effective utilization of renewable energy sources by balancing the long-term variations in production and consumption. However, current materials still require higher storage capacity, efficiency and reliability for large-scale use. Previously, we established that cold-crystallizing material (CCM), which consists of erythritol in a polymer matrix, can reliably store heat over three months without decreasing its storage efficiency. Heat is stored by cooling the melted CCM to deeply supercooled state (storage temperature at 0-10 °C) and released by heating the material to cold-crystallization temperature, which initiates crystallization (i.e. cold-crystallization). However, if the storage temperature of CCM was increased, stored melting heat would dissipate due to slow crystallization. This paper analyses cold-crystallization rate of CCM, in order to model and predict the storage efficiency at different storage temperatures. This was carried out by measuring the progress of cold-crystallization by differential scanning calorimetry (DSC) under multiple isothermal conditions. The crystallization data was first analysed by applying Avrami approach, to identify the crystallization rate constant. Then, the Arrhenius and the Williams-Landel-Ferry (WLF) models estimated the temperature dependence of the rate constant. DSC measurements yielded a storage efficiency of around 0.74 in the tested temperature range. Time evolution of this storage efficiency predicted with the WLF model corresponds to the experimental data indicating that valid predictions of CCM’s storage efficiency can be obtained, when storage temperature and time are known.
Original languageEnglish
Title of host publication Proceedings of the 14th International Renewable Energy Storage Conference 2020 (IRES 2020)
PublisherAtlantis Press
Pages186-192
Number of pages7
ISBN (Electronic)978-94-6239-327-1
DOIs
Publication statusPublished - 4 Feb 2021
MoE publication typeA4 Article in a conference publication
EventInternational Renewable Energy Storage Conference - Virtual, Online, Dusseldorf, Germany
Duration: 25 May 202026 May 2020
Conference number: 14

Publication series

NameAtlantis Highlights in Engineering
PublisherAtlantis Press
Volume6
ISSN (Electronic)2589-4943

Conference

ConferenceInternational Renewable Energy Storage Conference
Abbreviated titleIRES
CountryGermany
CityDusseldorf
Period25/05/202026/05/2020

Keywords

  • Long-term thermal energy storage
  • Phase change material
  • Supercooling
  • Cold-crystallization
  • Erythritol

Fingerprint

Dive into the research topics of 'Storage Efficiency of Cold-Crystallizing Long-Term Heat Storage Material'. Together they form a unique fingerprint.

Cite this