High-performance ultra-low-carbon Geopolymer heat Battery for thermochemical energy storage in net-zero buildings (GeoBattery)

Space heating currently accounts for 25% of the UK's energy consumption and 17% of its carbon emissions. The effective and efficient recovery, storage, and reuse of waste heat, together with renewable energy, play indispensable roles in decarbonisation of heating in buildings. The thermochemical energy storage materials possess the highest volumetric energy density comparing to phase change and sensible heat storage materials. However, the design and manufacture of thermochemical energy storage materials are still facing the challenges of high cost, low sustainability, and limited heating power. There also lacks fundamental understandings of the properties of materials that control the cyclic energy storage performances and structural stabilities. These have brought significant challenges to optimisation and implementation of the thermochemical energy storage techniques for domestic application.

This project adopts novel research approaches for civil engineering materials to tackle these standing challenges faced by developing thermochemical energy storage materials. Versatile high-performance heat battery materials will be developed from sustainable low-cost civil engineering material geopolymers. Lightweight geopolymer composite materials with enhanced heat and mass transport properties and thermochemical energy storage capacity will be developed through green synthesis routes. The first structural stability assessment model for predicting the service cycle life of heat battery materials will be proposed from the extended chemo-mechanical salt damage model for inorganic porous building materials. The materials fabrication technology and fundamental understanding of the degradation mechanism developed in this project will be transferable to versatile "salt-in-matrix" TCES composites. The outcomes developed from this project will drastically improve the sustainability and resilience of thermal energy storage technologies, for decarbonisation of heating in existing and new-built buildings.