Combined heat transfer in a system for solar heating and radiative cooling

Abstract

The goal of this work is to study a system, which covers both the demands for heating and cooling of a building. The system is designed to be one large central installation for storage and distribution. Such systems obviously reveal a large cost-competitiveness. The design foresees solar collectors for heating and radiative cooling panels, which could be combined with an external electric fan, for cooling the water in the storage. In the present system design, the heat storage tank is divided in several sections in order to allow domestic hot water heating and cooling (summer) or DHW- and space heating (winter). It was investigated how well the heating- and cooling gains could be separated for the demand during typical days during summer. The stratification has been studied in particular in this thesis, and especially with respect to energy considerations when using the system for cooling. The results of the experiments indicate that there are potential benefits of using this type of solar system for cooling. The gain in cooling energy has been found to be in the range of 5.4 kWh to 6.2 kWh and the stratification of the tanks were found to be adequate.