- Title
- High temperature materials for solar thermochemical energy storage
- Creator
- Fedunik-Hofman, Larissa
- Relation
- University of Newcastle Research Higher Degree Thesis
- Resource Type
- thesis
- Date
- 2021
- Description
- Research Doctorate - Doctor of Philosophy (PhD)
- Description
- This thesis discusses the development of energy storage materials suitable for high temperature solar thermochemical energy storage (TCES). The aim of the thesis is to improve the performance of current state-of-the-art CaCO3-CaO looping systems (CaL) for TCES. CaL is an emerging option for solar energy storage which is based on two reversible chemical reactions, calcination and carbonation, which can be cycled to store and release thermal energy. However, the commercial applicability of CaL is hindered because the materials lose conversion capacity with cycling due to the material sintering, which necessitates replacement. The research goal is hence to improve the cyclability and energy storage performance of CaL by developing enhanced sintering-resistant CaO-based energy sorbents. The materials are intended to be used in solar reactors using 100% CO2 gas systems and thus to be coupled with a supercritical CO2 cycle in a concentrating solar thermal power plant. The novel CaO-based energy sorbents developed and tested include Pechini-synthesised CaO; hydroxyapatite-doped CaO; CaO and SrO/BaO mixtures and Dy2O3 and Ca3Al2O6-supported CaO. The materials performance is tested under conditions which replicate solar TCES by using thermogravimetric analysis and differential scanning calorimetry. Furthermore, materials are characterised using techniques such as X-ray diffraction, scanning/transmission electron microscopy and N2 adsorption/desorption surface area analysis to support the performance results. Chemical reaction kinetics is an important aspect of material development which affects performance and reactor design and hence forms a key research area for CaL systems. The chemical kinetics of calcination and carbonation reactions for selected materials are analysed both under a 100% CO2 atmosphere and mixed inert/CO2 atmospheres using a comprehensive range of techniques. The kinetic methods implemented include model-fitting methods (i.e. Coats-Redfern), model-free methods (Friedman isoconversional method) and generalized methods (i.e. intrinsic chemical reaction rate and apparent models) and the kinetic parameters obtained are compared with relevant literature results. Long-term performance of the most promising materials is modelled and an economic evaluation is presented. The overarching impact of the thesis is to provide directions for novel TCES options with the potential to lower the costs and improve the deployment of concentrating solar thermal power technologies.
- Subject
- carbonate looping; calcium looping; thermochemical energy storage; carbon capture and storage; kinetics; solid-gas reactions; thesis by publication
- Identifier
- http://hdl.handle.net/1959.13/1431363
- Identifier
- uon:38951
- Rights
- Copyright 2021 Larissa Fedunik-Hofman
- Language
- eng
- Full Text
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| Thumbnail | File | Description | Size | Format | |||
|---|---|---|---|---|---|---|---|
| View Details Download | ATTACHMENT01 | Thesis | 11 MB | Adobe Acrobat PDF | View Details Download | ||
| View Details Download | ATTACHMENT02 | Abstract | 343 KB | Adobe Acrobat PDF | View Details Download |