NEW CONCEPT OF SOLAR COLLECTOR INTEGRATED INTO A SANDWICH PANEL AS AN ACTIVE FAÇADE; CFD BASED PARAMETRIC ASSESSMENT AND CASE STUDY

Abstract

The use of renewable energy sources is a clear commitment in the process of developing alternatives to reduce the high energy consumption in buildings. Although with intermittent production, renewable energies are unlimited and have a demonstrated potential to be integrated within buildings. The facade is a key element in a strategic position for harnessing renewable solar energy by means of the Active Solar Façade concept. Through a CFD model, a parametric study has been developed to evaluate different alternatives in the design of an Active Solar Facade, composed by a sandwich panel as unglazed solar collector. The high influence of the conductivity together with the absorptivity has been demonstrated. Directly linked to the material selection for solving the absorber and the hydraulic circuit, the advantage of metals compared with plastics, has been verified. The minor effect of the insulation has also been analyzed, although the necessity of a minimum quantity has been stated looking to avoid significant heat losses. Additionally, the performance of the system has been evaluated in order to determine the potentially achievable energy. The result of the extensive campaign monitored in KUBIK® and developed in different days in a period of 12 months, has resulted in an average daily production of 320Wh / m2. This study highlights the potential benefits of this type of solutions and the necessity to properly dimension and design them. In such way it is aimed to contribute to a greater use of renewable energy in buildings, and consequently for reducing the use of fossil fuels, by means of alternatives that enable the mitigation of the climate change.