Evaluation of a solar thermal glass façade with adjustable transparency in cold and hot climates

The paper presents the evaluation of a new glass façade system, titled FLUIDGLASS, which combines four functions in one element: a solar thermal collector, a heating/cooling device, a transparent thermal envelope and an adaptive shading system. The collector panel is a combination of fluid and glass layers. By controlling the temperatures or the transparency of the circulating fluid the passive façade is transformed into an active thermal system capable of reacting to changing environmental conditions. The expected impact is a significant improvement in the thermal performance of the building envelope and high thermal comfort for different climate zones. The validation by simulation and measurement results indicate that no additional energy beyond that which is provided by the façade element is necessary to reach the thermal comfort temperatures. Surpluses of solar collector gains can contribute to the usage on a district level with seasonal storage.