Abstract
In this paper, a literature review on thermocline storage performance for Concentrating Solar Power (CSP) plant storage systems has been conducted. The efficiency of materials to store heat depends on the storage process like sensible heat storage, latent heat storage and thermochemical one and also on their properties. This study has been focused on sensible heat storage materials especially thermocline storage system (DMT) using eco-materials which has a high potentiality (35%) to reduce CSP cost. There is a possibility to use natural rocks, industry waste and to develop also materials for a thermocline storage within a bed called packed bed using one tank. The thermal storage materials should have some optimum parameters (particle diameter less than 2 cm and good thermo-physical properties) to achieve better thermal storage performance (thermal cycle efficiency, extraction factor). However, the size and the shape of natural rocks are uncontrollable (big diameter) and can drive to thermocline degradation, catastrophic thermal ratcheting and poor thermal stratification due to the variability of the storage system porosity and the stress on the storage tank wall. Also a better thermal storage efficiency is achievable at low velocity and with good thermo-physical properties of the HTF. The ratio H/D, the height, the porosity, the shape and the position of the tank should be optimized to increase the storage efficiency.
Highlights
The global demand for energy is growing and conventional resources like coal and petroleum are depleting, renewable resources is expected to play a crucial role in the future
This study has been focused on sensible heat storage materials especially thermocline storage system (DMT) using eco-materials which has a high potentiality (35%) to reduce Concentrating Solar Power (CSP) cost
This enables liquid/solid systems to operate at low heat transfer fluid (HTF) velocity while keeping a good heat transfer coefficient (HTC), which improves thermal stratification [59]
Summary
The global demand for energy is growing and conventional resources like coal and petroleum are depleting, renewable resources is expected to play a crucial role in the future. CSP technology affordability is suffering from energy storage system for electricity dispatching during the night-time and cloud cover This is explained by the important initial investment of 15% to 20% due to the two-tank storage system and the high price of heat transfer fluid (HTF) like mineral oil and synthetic oil, use as storage medium since 1984 at SEGS plant [2]. Another challenge of mineral oil is the high risk of flammability, for example in 2009 the solar field of Andasol CSP plant in Spain took fire [3] To face these challenges in 2004, an engineering study has shown the possibility of reduction of 10% of levelized electricity cost using molten salt in the medium storage [2]. With more focused on DMT system the effects of some key design parameters such as the inlet temperature and fluid flow (velocity), fluid properties, filler materials diameter and their thermal properties, tank porosity, and the tank aspect ratio, shape and position on the thermal performance of the thermocline TES are presented based on literature analysis
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
