Setting up of a thermochemical energy storage test rig using silica gel

Abstract

The current global crisis of carbon dioxide (CO2) emissions from human activities highlights the need to shift away from these practices and prioritize the use of renewable energy sources. One of the key challenges associated with renewables is the issue of intermediaries. This study aims to dive deeper into the field of Thermochemical energy storage, which presents a promising solution for addressing the intermittency of renewable energy sources by storing and releasing energy through reversible chemical reactions. The project aims to investigate the energy storage and release capabilities of a silica gel-based thermochemical energy storage system by setting up a test rig in the thermodynamics laboratory using readily available and low-cost materials. This project focuses on the design, construction, testing and control of a thermochemical energy storage test rig utilising silica gel as the storage medium and air as a working fluid. Silica gel is an environmentally friendly material that also possesses high energy density, making it the ideal candidate to be used as a thermochemical material. The test rig controls the psychometry and temperatures of the working fluid to simulate the charging and discharging processes of the silica gel fixed-bed reactor, which is done through a lab-made humidifier and heating elements. A performance analysis was carried out to determine the effectiveness of the control parameters present in the test rig, which consisted of a PI controller. The experimental setup allows for the investigation of key parameters affecting the performance of the thermochemical energy storage system, including temperature, humidity, and flow rate. The reactor’s behaviour during the charging and discharging processes was closely monitored and analysed through a graphical user interface, whilst an efficiency analysis of the energy stored and released from the reactor was also carried out. Overall, this research contributes to the advancement of sustainable energy storage solutions, with potential applications in renewable energy integration and grid stabilisation.