Using Controlled Active Mass (CAM) to decrease energy demand for cooling

Overheating in summer is a problem in buildings with large glass area and low heat capacity constructive materials. Adding some thermal mass to the building is a way to overcome this problem. A new method is using removable thermal mass. This is called Controlled Active Mass (CAM). The CAM is an extra thermal mass which is placed inside the building to decrease energy demand for cooling and heating. In this work different aspects of refilling a CAM have been studied using numerical analysis. Here the CAM has been selected as a water storage which the water is refreshed every morning. A CAM with water inside has been modeled in a light weight room. The indoor climate of the room and energy demand has been studied when the CAM was refilled with cold water each morning. The CAM and the room have been modeled and simulated using the Simulink toolbox of Matlab and IBPT (International Building Physics Toolbox). The simulation has been done using weather data for a whole year in Göteborg, Sweden. The simulation results show that refilling the CAM in a light weight room works well when the temperature is lower than a certain temperature. This temperature depends on the size and properties of the CAM and room. Selecting an optimum format for a CAM inside a room and the time and period of refilling depends on the size, material and location of the CAM and also the time duration.