MiniStor (Minimal Size Thermal and Electrical Energy Storage System for In-Situ Residential Installation) is a project funded by the European Union’s Horizon 2020 research and innovation programme. The MiniStor project aims at designing and producing a novel compact integrated thermal storage system for achieving sustainable heating, cooling and electricity storage that can be adapted to new and existing systems in residential buildings. It is based on high performing thermo-chemical material reaction combined with hot and could PCM. Eighteen partners across the European Union, Switzerland and the UK work together to harness the large potential of EU buildings to increase its energy efficiency performance by providing a new and innovative solution. MiniStor´ system optimizes the use and management of thermal energy by allowing it to be stored, levelling demand peaks and increasing the use of renewables affected by intermittency such as solar-based heating.