摘要
Compressed Air Energy Storage(CAES)is one of the methods that can solve the problems with intermittency and unpredictability of renewable energy sources.A side effect of air compression is a fact that a large amount of heat is generated which is usually wasted.In the development of CAES systems,the main challenge,apart from finding suitable places for storing compressed air,is to store this heat of compression process so that it can be used for heating the air directed to the expander at the discharging stage.The paper presents the concept of a hybrid compressed air and thermal energy storage(HCATES)system,which may be a beneficial solution in the context of the two mentioned challenges.Our novel concept assumes placing the thermal energy storage(TES)system based on the use of solid storage material in the volume of the post-mining shaft forms a sealed air pressure reservoir.Implementation of proposed systems within heavily industrialized agglomerations is a potential pathway for the revitalization of post-mine areas.The potential of energy capacity of such systems for the Upper Silesian region could exceed the value of 10 GWh.In the paper,the main construction challenges related to this concept are shown.The issues related to the possibility of storing air under high pressure in the shaft from the view of the rock mass strength are discussed.The overall concept of the TES system installation solution in the shaft barrel is presented.The basic problems related to heat storage in the cylindrical TES system with a non-standard structure of high slenderness are also discussed.The numerical calculations were based on the results of experiments performed on a laboratory stand,the geometry of which is to reflect the construction of a TES tank in a post-mining shaft.The article presents the results of numerical analysis showing the basic aspects related to difficulties that may occur at the construction stage and during the operation of the proposed HCATES system.The paper focuses on the methodology for determining the energy and exergy efficiency of a section of a Thermal Energy Storage tank,and presents the differences in the performance of this tank depending on its geometric dimensions,which are determined by the different sizes of mine shafts.
