Modelling High-Temperature Thermal Storage Systems for Concentrated Solar Power Plants
type: CreativeWork
description: Thermal energy storage (TES) is an important aspect of concentrated solar power (CSP) systems addressing the mismatch between electrical demand and supply profiles and intermittency in the solar resource. The design of TES components should be optimised from a system-level perspective to minimise the cost of electricity generation and maximise energy yield of a CSP system. This thesis presents models of two different TES concepts for high-temperature sodium-based CSP systems in the \textit{OpenModelica-SolarTherm} system modelling framework. The first TES concept modelled was a novel integration of PCM storage component with a sodium tubular boiler CSP receiver at a 1 MWe scale. The goal of the study was to determine the techno-economic feasibility of this novel concept, which combines the benefits of a high-temperature power cycle and a low-cost NaCl PCM with the drawbacks of a high-temperature receiver and increased cost of temperature-resistant infrastructure. A multi-objective optimisation of heliostat field, receiver and detailed storage geometry was performed to minimise the levelised cost of electricity (LCOE) and maximise capacity factor of the sodium-boiler system and a reference, conventional 100 MWe two-tank molten salt system. For a polar field with billboard sodium receiver configuration, an optimised LCOE of 128.3 USD/MWhe was obtained, which was higher than the 107.1 USD/MWhe obtained for the reference system. The sodium-boiler concept could still be promising for small scale, fringe-of-grid applications. The system-level analysis identified areas for improvement, namely receiver flux limits, receiver thermal losses and the high cost of temperature-resistant storage materials. The second TES concept modelled was a packed-bed storage tank with sodium fluid and MgO filler operated as a thermocline, this validated against experimental data. A detailed system model which integrates a dynamic thermocline TES model into a full annual simulation was develope…
abstract: Thermal energy storage (TES) is an important aspect of concentrated solar power (CSP) systems addressing the mismatch between electrical demand and supply profiles and intermittency in the solar resource. The design of TES components should be optimised from a system-level perspective to minimise the cost of electricity generation and maximise energy yield of a CSP system. This thesis presents models of two different TES concepts for high-temperature sodium-based CSP systems in the \textit{OpenModelica-SolarTherm} system modelling framework. The first TES concept modelled was a novel integration of PCM storage component with a sodium tubular boiler CSP receiver at a 1 MWe scale. The goal of the study was to determine the techno-economic feasibility of this novel concept, which combines the benefits of a high-temperature power cycle and a low-cost NaCl PCM with the drawbacks of a high-temperature receiver and increased cost of temperature-resistant infrastructure. A multi-objective optimisation of heliostat field, receiver and detailed storage geometry was performed to minimise the levelised cost of electricity (LCOE) and maximise capacity factor of the sodium-boiler system and a reference, conventional 100 MWe two-tank molten salt system. For a polar field with billboard sodium receiver configuration, an optimised LCOE of 128.3 USD/MWhe was obtained, which was higher than the 107.1 USD/MWhe obtained for the reference system. The sodium-boiler concept could still be promising for small scale, fringe-of-grid applications. The system-level analysis identified areas for improvement, namely receiver flux limits, receiver thermal losses and the high cost of temperature-resistant storage materials. The second TES concept modelled was a packed-bed storage tank with sodium fluid and MgO filler operated as a thermocline, this validated against experimental data. A detailed system model which integrates a dynamic thermocline TES model into a full annual simulation was develope…
author: Kee, Zebedee
language: en_AU
date published: 2024
date modified: 2026-07-24T00:54:57Z
provider: Australian National University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Australian National University

PropertyValue
property ID: Handle
value: https://hdl.handle.net/1885/733713072